List of articles (by subject)
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Open Access Article
1 - Dissimilar welding of UNS 2205 duplex stainless steel/AISI 316L austenitic stainless steel by pulsed current GTAW and joint properties evaluation
رضا نیسی مرتضی شمعانیان -
Open Access Article
2 - The Synthesis Of Nanocomposites (MoSi2-20% TiC) is activated by chemical Combustion Synthesis Method (COSHS)
مهدی بدرلو سید علی طیبی فرد محمد ذاکزیAdd titanium carbide in the compound molybdenum disilicide to increased mechanical strength. in this research element of the raw materials used to form MoSi2-TiC nanocomposite. the plan in this research procedure was based on combustion synthesis, chemical activation me MoreAdd titanium carbide in the compound molybdenum disilicide to increased mechanical strength. in this research element of the raw materials used to form MoSi2-TiC nanocomposite. the plan in this research procedure was based on combustion synthesis, chemical activation mechanism (COSHS). in this study, activation of elemental powders Mo, Si, Ti and C were used in chemical oven. first, on the basis of stoichiometric silicon powder raw materials including metal powder, molybdenum, titanium and carbon powder were prepared on the basis of 20% by weight of titanium carbide. to identify chemical compounds that react with itself, provides the heat necessary to react original composition (chemical oven), of compounds that have high ΔG was used. powders and tablets are pressed by uniaxial compaction of composite samples were prepared and chemical oven. synthesizing is done in atmospheric argon controlled tubular furnace the temperature between 700 - 1100 °C. to identify phases, xrd analysis and to evaluate morphology, sem and tem images were used. results show that the best process conditions for synthesis MoSi2-TiC nanocomposite with COSHS method were: temperature 850 °C selected as optimum conditions and composition (8Al + 4Mg + 3SiO2 + 5TiO2) as suitable chemical oven. the grain size calculation by reitveld method showed the size of titanium carbide crystallite and molybdenum disilicide in optimum condition of approximately was 77 nm and above 100 nm respectively. considering the images of sem and tem proved that a nanostructure composite has been synthesized Manuscript profile -
Open Access Article
3 - Influence of SiC particles on hot deformation behavior of closed cell Al/SiCp foam
آرمین دهنوی غلامرضا ابرهیمی مسعود گلستانی پورIn this research, closed-cell aluminum foams reinforced by SiC particles were fabricated using direct melt-foaming method and CaCO3 as a blowing agent. The effect of adding reinforcement particles on mechanical properties of foams was investigated by adding different vo MoreIn this research, closed-cell aluminum foams reinforced by SiC particles were fabricated using direct melt-foaming method and CaCO3 as a blowing agent. The effect of adding reinforcement particles on mechanical properties of foams was investigated by adding different volume percentages of SiC particles (3%, 6%, and 10%). To obtain the mechanical properties of produced foams, uniaxial compression test was carried on samples at different temperature (100°C, 200°C, 300°C, and 400°C) and constant strain rate equal to 0.1s-1. The compression tests result show that at the constant temperature, the yield stress, Plateau stress and energy absorption stresses of composite foams will increase by increasing the volume percentage of SiC particles and decrease with increase in temperature. Reinforcement particles also increase the number of indentation in the stress-strain curve of foams, which reflects increasing brittleness of the foams’ cell wall. Manuscript profile -
Open Access Article
4 - بررسی تاثیر فاصله توقف بر مورفولوژی و خواص مکانیکی فصل مشترک اتصال انفجاری صفحات سه لایه ضخیم AlMg5-Al-Steel
محمدرضا خانزاده قره شیران امیر اکرامی حمید عربی -
Open Access Article
5 - تاثیر قرار دادن لایه نازک سیلیکون در زیر غشای دی‌الکتریک بر روی عملکرد یک میکروهیتر
فاطمه سمایی فر احمد عفیفی حسن عبداللهی -
Open Access Article
6 - بهبود ریزساختار و خواص مغناطیسی فریت‌های لیتیم تولید شده به روش حالت جامد بوسیله افزودنی نانوسیلیکا
محمود محمودی مجید کاوانلویی -
Open Access Article
7 - Fabrication and investigation mechanical properties of Aluminum 7014 / alumina Nano composite powder by mechanical alloying
دانیال داودی امیر حسین امامی علی سعیدی -
Open Access Article
8 - The Effects of Current Density and pH on the Electrode position of Fe-Ni Alloy and Efficiency Parameters
آمنه وحیدیان علی سعیدی محمد علی گلعذار -
Open Access Article
9 - Coating ZnO nanowires on gold interdigitated array electrodes and investigating the functioning of alcoholic nano gas sensors
حمید غیور امین نکوبین امیرعباس نوربخشInterdigitated array electrods1 were prepared by nanolithography of gold on alumina substrate via PVD method. ZnOnanorods used as sensor were synthesized by hydrothermal method on a spotter-coated seed layer of zinc oxide. The synthesized nanorods were characterized by MoreInterdigitated array electrods1 were prepared by nanolithography of gold on alumina substrate via PVD method. ZnOnanorods used as sensor were synthesized by hydrothermal method on a spotter-coated seed layer of zinc oxide. The synthesized nanorods were characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM). Sensor functioning was investigated with regard to four alcoholic gases. In order to improve the sensing conditions, the sensitivity and response of ZnOnanorods in the temperature range of 50-300°C were studied. The working temperature of 47°C was selected as the optimal temperature and important variables such as sensitivity of the sensor, response time, and recovery time were obtained for the four testing gases at constant temperature and different concentrations. Results revealed that by usingZnO array nanorods,alcoholic gases with highsensitivity can be detected. Manuscript profile -
Open Access Article
10 - Investigation the effects of SiC reinforcement incorporation on mechanical properties of friction stir welded AZ31 magnesium alloy
AMIN ABDOLLAHZADEH Ali shokouhfar حمید امیدوار محمد علی صفرخانیان محمدرضا نادریIn this study, the friction stir welding process was used for simultaneously joining of AZ31 magnesium alloy and production of Mg/Sic nanocomposite in the stir zone. All combinations of three rotational speeds i.e, 600, 800, and 1000 rpm and four traveling speeds i.e, 2 MoreIn this study, the friction stir welding process was used for simultaneously joining of AZ31 magnesium alloy and production of Mg/Sic nanocomposite in the stir zone. All combinations of three rotational speeds i.e, 600, 800, and 1000 rpm and four traveling speeds i.e, 25, 75, 125 and 175 mm/min were tested and then the mechanical properties were examined. The joint fabricated with rotational speed of 800 rpm and traveling speeds of 75 mm/min, exhibited the highest mechanical properties, So that the yield strength, tensile strength and percent elongation improved by 11%, 39% and 88%, respectively. The results show that the proper distribution of nanoparticles in the stir zone can reduce the average grain size and improve mechanical properties. The main reason for this change is related to pinning effect and increased nucleation sites associated with SiC nano-particles. Moreover, reinforcement particles resulted in breaking of primary grains in stir zone of friction stir welding. Manuscript profile -
Open Access Article
11 - Transient liquid phase (TLP) bonding of AISI321 stainless steel using MBF-20 commercial interlayer
محمد علی میثاقی رضا بختیاریAccording to the industry’s need to an appropriate bonding process for components made of AISI 321 austenitic stainless steel, which is used in power-plant parts such as turbines, transient liquid phase (TLP) bonding of AISI 321 steel using MBF-20 interlayer MoreAccording to the industry’s need to an appropriate bonding process for components made of AISI 321 austenitic stainless steel, which is used in power-plant parts such as turbines, transient liquid phase (TLP) bonding of AISI 321 steel using MBF-20 interlayer was studied in this research. TLP bonding was performed in a vacuum furnace at 1050, 1100, 1150 and 1200oC for 30-120 minutes. The microstructural studies were conducted on the joints using an optical microscope and an scanning electron microscope (SEM). Phase analysis of the joints was also performed a SEM/EDS and XRD system. To investigate the distribution of elements across the joints, line scan analysis was used. The shear strength test and the micro hardness measurement test were conducted on the joints, in order to study the joints’ mechanical properties. The minimum time of complete isothermal solidification at 1050, 1100 and 1150oC was obtained as 75, 45 and 30 minutes, respectively. At the incomplete isothermal solidification condition, Fe-B, Cr-B, Ni-Si and Ni-B phases were observed at the joint centerline and diffusion affected zone (DAZ). With increasing bonding temperature and time, more homogenous joint, lower hardness at the different zones of the joints and higher shear strength were obtained. But for the joints made at 1200oC, higher than the critical bonding temperature, the joint shear strength was reduced. For the joints made at 1150oC for 60 minutes and also at 1050oC for 120 minutes, the maximum shear strength was obtained as 95 and 94 percent of that of the base metal, respectively. Manuscript profile -
Open Access Article
12 - Effect of Cr/C ratio on Microstructure and Thermal Fatigue life of the Fe-Cr-C Hardfacing alloy
حامد ثابتIn this Investigation two type of hard face coated electrodes (Fe-Cr-C) used as a hard facing alloys with different ratio Cr/C. The welding of hard facing electrodes were done in similar heat-input but in different of deposited layers on ST32 mild steel. The OES, OM, SE MoreIn this Investigation two type of hard face coated electrodes (Fe-Cr-C) used as a hard facing alloys with different ratio Cr/C. The welding of hard facing electrodes were done in similar heat-input but in different of deposited layers on ST32 mild steel. The OES, OM, SEM and XRD techniques used for determining of chemical analysis and study of microstructure characteristics of hard face samples. In addition the thermal fatigue test were done at 600-25 OC for different samples and hardness test used for determining the hardness of hard face layers. The XRD examination Results indicated that microstructure of hard facing layer sample (AB electrode) includes primary carbides and eutectic (), the microstructure of hardfacing layer sample (SD electrode) includes austenite+martensite. The hardness result indicated that hardfacing samples (AB electrode) have maximum hardness which 52-58HRC and hard facing samples (SD electrode) with austenite + martensite microstructure have minimum Hardness (30-50 HRC). The thermal fatigue Test results indicated, the highest fatigue life related to the sample that hard-faced with the SD electrode (Ø=4 mm) at a single layer and the lowest thermal fatigue life related to the sample that hard-faced with AB electrode (Ø=3.25 mm) at two layers. It was also found that there is an inverse relationship between hardness and thermal fatigue life of specimens. Manuscript profile -
Open Access Article
13 - Similar and dissimilar 5754 and 6063 aluminum alloy joints by friction stir welding
امین ربیعی زاده احمد افسری فرهاد ارغوانی فرناز احمدی کیسمیThe relatively new solid state welding process friction stir welding (FSW) was applied in this research work to join similar and dissimilar aluminum alloys AA5754-H22 and AA6063-T4. Different welding rotational speed and transverse speed applied. The joint which was fab MoreThe relatively new solid state welding process friction stir welding (FSW) was applied in this research work to join similar and dissimilar aluminum alloys AA5754-H22 and AA6063-T4. Different welding rotational speed and transverse speed applied. The joint which was fabricated using tool rotational speed of 2000 rpm and transverse speed of 4 mm/min yielded the best mechanical properties. Soundness of joint was proved by non-destructive tests such as visual inspection and radiography. The global mechanical behavior of the similar welds is very similar to that of the base material. For dissimilar weld important losses in ductility was reported. Microstructural evaluation of fractured surface showed that ductile fracture was the major fracture mechanism of similar and dissimilar welds. Manuscript profile -
Open Access Article
14 - Evaluation of Microstructure and Mechanical Properties of Friction Stir Lap Welded 6061 Aluminium Alloy at various welding speeds
فرهاد غروی ایمان ابراهیم زاده علی سهیلیIn this research the AA 6061-T6 aluminium alloy plates were welded by friction stir lap welding method. The effect of welding speeds on micro- and macro-structures and mechanical properties was investigated. The welding process was conducted by welding speed in the rang MoreIn this research the AA 6061-T6 aluminium alloy plates were welded by friction stir lap welding method. The effect of welding speeds on micro- and macro-structures and mechanical properties was investigated. The welding process was conducted by welding speed in the range 20-60 mm/min at constant rotation speed of 1000 rpm. The results showed that with increasing of welding speed, tensile shear strength and joint efficiency were increased from about 126 to 132 MPa and from about 40.6 to 42.5 (%), respectively. Although average micro-hardness of the weld nugget zone (WNZ) rather than the heat affected zone (HAZ) were increase with increasing welding speed, the average grain size in the WNZ and in the HAZ was decreased from about 43 to 32 µm and from about 99 to 87 µm, respectively. Due to increasing welding speed, the EPT with an increase in welding speed the hooking and thinning defects were gradually restricted from the WNZ to the WNZ/TMAZ interface. The fracture mode within the highest tensile shear strength joints was denoted as plate separation along the hook throughout the stir zone. Manuscript profile -
Open Access Article
15 - Investigation nitride coating surface properties and wear on the hot work tool steel AISI H11 in the method pulsed plasma nitriding
کیانوش طاهرخانی خیرالله محمدی حسین تارقلی زادهIn this research, the effects of plasma nitriding parameters investigated on samples with different geometry. Samples were prepared were nitrided under the atmosphere content of 20%H2-80%N2, at the temperature of 520 c, the duty cycles of 30%, 50%, 80% and with frequenc MoreIn this research, the effects of plasma nitriding parameters investigated on samples with different geometry. Samples were prepared were nitrided under the atmosphere content of 20%H2-80%N2, at the temperature of 520 c, the duty cycles of 30%, 50%, 80% and with frequencies of 10 kHz for 6 hours. Then the property of grooves surfaces investigate by experiments of the SEM, Roughness and Micro Hardness measurement. The results of the experiments showed that the surface of the plasma nitriding samples are covered by cauliflower form of particles that formation of this particles in plasma nitriding samples are due to sputtering of the surface during the process. With increasing thickness of the groove, frequency and duty cycle, roughness of surfaces raise. Also micro hardness rise with increasing the thickness of the groove and duty cycle resulting from the increase in percent of deposition particle nitride. The Hollow cathode phenomena occurred in sample with 2mm groove and 80% duty cycle in CPN. This will result in over heating of the sample which leads to a decrease hardness of the surface and an increasing in the Roughness of the surface. Then after the process plasma nitriding, the results of the pin on disk wear test showed that the nitrides coating have wear resistance better than the reference sample before treatment plasma nitriding. Manuscript profile -
Open Access Article
16 - Investigation of kinetics behavior high temperature isotherm oxidation MCrAlY coatings applied by HVOF method
Seyed sina khalifeh soltani Reza ebrahimi kahrizsangi Farid naeimiToday, in Power plant industry, especially gas turbine hot corrosion and oxidation resistance of high temperature superalloys used. These superalloys good resistance to attack and entry of hot gases and ash fines resulting from fuel combustion, as well as atmospheric co MoreToday, in Power plant industry, especially gas turbine hot corrosion and oxidation resistance of high temperature superalloys used. These superalloys good resistance to attack and entry of hot gases and ash fines resulting from fuel combustion, as well as atmospheric corrosion of the show. As a result of these superalloys used in Power plant industry, especially are considering today. The thermal spray coating on these superalloys can be hot corrosion resistance and high temperature oxidation increase. In this research isothermal oxidation behavior of CoNiCrAlY coating and kinetic of growth thermally grown oxide layer (TGO) was investigated. For deposit of the CoNiCrAlY Amdry 9954 coating on superalloy nickel-base (Inconel 738) substrate used to the high-velocity oxygen-fuel (HVOF) technology. These specimens coatings were oxidized at 1100°C for 5 upto 100 h in a normal electric furnace under air atmosphere. The test specimens were examined using scanning electron microscope (SEM) and energy dispersive spectrometry analysis (EDS) together with the X-ray diffraction (XRD) analysis. Microstructural characterization showed that the growth of continuous and uniform TGO scale onto bond coat. Also, in oxidation process observed the formation of mixed oxides (as spinel) CoCo2O4 and Ni(Cr,Al)2O4 and CrO3 and Y3Al5O12 onto Al2O3 (TGO layer). Manuscript profile -
Open Access Article
17 - The effects of deposition variable on the pulse electrodeposition FeNi-WC nanostructure composite
آمنه وحیدیان علی سعیدی محمد علی گلعذارThe increasing demand for magnetic materials in the industry has led to the production of Fe-Ni composite magnetic alloys with ceramic particles. In this research, FeNi-WC nanostructure composite was produced using pulse electrodeposition. The effects of pH, current den MoreThe increasing demand for magnetic materials in the industry has led to the production of Fe-Ni composite magnetic alloys with ceramic particles. In this research, FeNi-WC nanostructure composite was produced using pulse electrodeposition. The effects of pH, current density and the amount of reinforcement on composition and morphology of products were examined, because morphology and chemical composition and structure of samples were studied by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) and X-ray diffraction analysis (XRD). The result showed an increasing pH, increased slightly nickel and decreased iron, and spherical morphology led to change star one. Due to importance of energy saving, effects of variables on the efficiency parameters such as the current efficiency and specific energy consumption were studied. By increasing pH, current efficiency was increased and specific energy consumption was reduced. When the current density increased, current efficiency was reduced and specific energy consumption was increased. In general, more current density (100 mA/cm2) and lower reinforcement (5 g/L) was observed more uniform morphology. Manuscript profile -
Open Access Article
18 - Investigation of hydrogen desorption temperature of MgH2-10wt% (Ti, Mn, V and Fe) nanocomposite produced by mechanical alloying
حسین محمدی سید جمال حسینی پور محمد رجبیMagnesium hydride is one of the attractive hydrogen storage materials because of its hydrogen storage capacity (7.6 wt %), low cost and light weight. However, high hydrogen desorption temperature and a high reactivity toward oxygen limit the use of MgH2 in practical app MoreMagnesium hydride is one of the attractive hydrogen storage materials because of its hydrogen storage capacity (7.6 wt %), low cost and light weight. However, high hydrogen desorption temperature and a high reactivity toward oxygen limit the use of MgH2 in practical applications. Many efforts have focused on Mg-based hydrides in recent years to reduce the desorption temperature. These can be accomplished to some extent by changing the microstructure of the hydride by mechanical alloying and also by using proper catalysts. In this work, Ti, Mn, V and Fe elements were added to MgH2 either in the form of powder mixture or prealloyed powder and after 30 h mechanical alloying, the properties of obtained nanocomposites were investigated by X-ray diffractometery, scanning electron microscopy and thermal analysis. The results showed that the addition of prealloyed powder to MgH2 and 30 h mechanical alloying of powder mixture is more effective in dehydrogenation properties. Manuscript profile -
Open Access Article
19 - Investigation of effect of tool geometry on formation of common defects, and mechanical properties of 5456 Aluminum alloy, in Friction Stir Lap Welded process
MOHAMMADREZA NADERI محمد علی صفرخانیان امیر حسین کوکبی امین عبداله زادهFriction stir welding is suitable for joining series 5000 alloys because no fusion welding problems arise for the alloys in this process. In this project, the effect of tool geometry on mechanical properties and formation of common defects in FSW such Kissing Bond defec MoreFriction stir welding is suitable for joining series 5000 alloys because no fusion welding problems arise for the alloys in this process. In this project, the effect of tool geometry on mechanical properties and formation of common defects in FSW such Kissing Bond defect and Hooking was investigated. Specimens were welded with three pin, that is, Cone with stair (stair at intersection of two sheets), frustum, and Tri-flute (rotating speeds: 650 , 500 rpm / welding speeds: 50, 25 mm/min). First, the macrostructure and microstructure of weld sections was investigated, and afterwards tensile shear test from retreating side as well as micro hardness test were examined. The results show that from among three pins which were used in this project, Tri-flute is the best pin simply because the specimens which were welded with this pin not only had an appropriate Hooking height, but also Kissing Bond was not destructive in these specimens. Manuscript profile -
Open Access Article
20 - Effect of TiO2 Content of the Slag of Electro Slag Remelting Process on Chemical Composition, Microstructure and Mechanical properties of Recycled IN713LC
مرتضی زمانی معصومه سیف اللهی سید مهدی عباسیRecycling of industrial scrap of IN317LC superalloys via ESR process is investigated in this article. The purpose of this study is reach to the best chemical composition, microstructure and mechanical properties according to AMS5377E standard. Different levels of TiO2 ( MoreRecycling of industrial scrap of IN317LC superalloys via ESR process is investigated in this article. The purpose of this study is reach to the best chemical composition, microstructure and mechanical properties according to AMS5377E standard. Different levels of TiO2 (0, 3, 6 wt %) were added to 70CaF2-30Al2O3 ESR slag. The results show that in slag wih 3 wt % TiO2, Ti loss compensate by Oxidation-Reduction reaction between slag and melt. As a result of the variation of slag activity, oxygen and nitrogen of the recycled ingot reach to 14.3 and 16 ppm, respectively. In addition, this ingot has the maximum level of γ' particle with minimum size because of high level of (Ti+Al) of this recycled alloy, the good microstructure and the stress rupture life of 47 hr obtained. In the recycled ingot by 6 wt % TiO2, despite of compensation of Ti loss and increase of Ti level, the mechanical properties reduced as a result of reduction of γ' volume fraction. Manuscript profile -
Open Access Article
21 - Investigation of microstructure and mechanical properties of AISI304L Stainless Steel to ASTMA514 Steel joint by Gas Tungsten Arc Welding
موسی توکلی عباس سعادت محمدرضا خانزاده قره شیرانIn the present study, Dissimilar welding of austenitic stainless steel AISI 304L to Quenched and Tempered Steel ASTM A514 was investigated by gas tungsten arc welding process. Two filler metals including (ERNiCr-3) and austenitic stainless steel 309l (ER309L MoreIn the present study, Dissimilar welding of austenitic stainless steel AISI 304L to Quenched and Tempered Steel ASTM A514 was investigated by gas tungsten arc welding process. Two filler metals including (ERNiCr-3) and austenitic stainless steel 309l (ER309L) were used. Microstructure of nugget, heat affected zone, inter face and unmixed zone (UMZ) was studied by optic microscopy and scanning electron microscopy equipped with energy disperse spectrometry (EDS). The investigations showed completely austenitic structure as dendrite for ERNiCr-3 weld metal and primary ferrite with austenitic matrix for 309l weld metal. Mechanical properties including tensile and bending strength, impact resistance, hardness and fractography of the specimen was studied. The entire specimen underwent ductile fracture in HAZ in the tension test. Tensile strength in ER309L and ERNiCr-3 had increment of 556 Mpa and 593 Mpa respectively. Impact thoughtless in join induced by ERNiCr-3 filler was 117 J while it was 95 J for ER309L. The maximum and minimum hardness was related to the ERNiCr-3 (156 Vickers) and ER309L (127 Vickers), respectively. Finally, according to mechanical properties, it can be concluded that in dissimilar welding of austenitic stainless steel AISI 304 L to Quenched- Tempered Steel ASTM A514, The ERNiCr-3 filler is better than ER309L. Manuscript profile -
Open Access Article
22 - The Effect of Electrical Discharge Machining Parameters On 2024 Aluminum-Based Composite Material Using Calculation and Analysis of the Total Normalized Quality Loss and Signal-to-Noise Analysis
Behnam Masoudi saeed daneshmandMetal matrix composites, according to the type of reinforcement used, have a different machinability. 2024 Aluminum matrix composites reinforced with aluminum oxide is among the materials the machining of which through traditional methods leads to the rapid wear of the MoreMetal matrix composites, according to the type of reinforcement used, have a different machinability. 2024 Aluminum matrix composites reinforced with aluminum oxide is among the materials the machining of which through traditional methods leads to the rapid wear of the tool; hence, EDM is a suitable method for machining this class of materials. Given that this machining method has different parameters, optimal set of machining parameters has a major effect on machining time, surface quality and tool wear rate. Using calculation and analysis of the total normalized quality loss (TNQL) and simultaneous signal to noise ratio of the outputs, this research is an attempt to investigate the effect of EDM parameters including current intensity, voltage, pulse on-time, and pulse off-time on material removal rate, tool wear rate and surface roughness in a the states of with and without powder and rotary tool. The results showed that current intensity and then pulse on-time, pulse off-time, and voltage have respectively the most important effect on output parameters of machining. The use of aluminum oxide powder and rotary tool increases gap and creates a centrifugal force and hence moves particles away from the area of machining and finally increases MRR. The use of aluminum powder in collision with sparks makes the sparks smaller and reduces their penetration depth and, thus, reduces the surface roughness. The results of optimization without powder and rotary tool proposes the combination of parameters as A3B1C2D3 while with powder and rotary tool proposes the combination of parameters as A1B1C2D3. Manuscript profile -
Open Access Article
23 - An investigation on the production of activated carbon from olive stone
Hadi Sharifi Darabad Mandana AdeliActivated carbon is a porous material which has found extensive applications in separation and purification processes. Special properties of this material such as high specific surface area, highly porous structure, and high absorption capacity have resulted in its util MoreActivated carbon is a porous material which has found extensive applications in separation and purification processes. Special properties of this material such as high specific surface area, highly porous structure, and high absorption capacity have resulted in its utilization in numerous industries. The purpose of this research is the production of activated carbon from waste olive stones using the chemical activation method. Phosphoric acid was used to chemically activate the olive stones, and a reductive atmosphere was applied in the heating stage instead of inert gas atmosphere. The effect of such parameters as acid concentration and activation temperature on the product properties were investigated. The products were characterized using XRD, SEM, and BET analysis. It was found out that the production of high-quality activated carbon is possible without the need for an inert heating atmosphere. It was also concluded that the concentration of the soaking solution highly affects the properties of activated carbon, especially its specific surface. The optimum conditions for obtaining the highest specific surface in the activated carbon (1194.94 m2/g) were determined to be 85 wt.% concentration of acid soaking solution, and heating temperature of 500°C. Manuscript profile -
Open Access Article
24 - Investigation of adding Cr2O3 on mechanical properties and high temperature oxidation behavior of Stellit6 coating prepared by plasma spraying on IN-738
mostafa tahari Mohammad Gavahian Mohammad Jahanbaze Mohammad NajafiIn this study, the effect of adding chromium oxide on mechanical properties and high temperature oxidation behavior of thermal sprayed stellite 6 coating on IN-738 has been investigated. For this purpose, first the 0, 10, 20 and 30 %wt. Cr2O3 powder added to satellite6 MoreIn this study, the effect of adding chromium oxide on mechanical properties and high temperature oxidation behavior of thermal sprayed stellite 6 coating on IN-738 has been investigated. For this purpose, first the 0, 10, 20 and 30 %wt. Cr2O3 powder added to satellite6 and plasma sprayed on the IN_738 substrate after mixing by mechanical milling. The optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffractometer (XRD) and micro-hardness used for micro-structure, porosity and phase analysis investigation. The isothermal oxidation behavior of composite coatings at 650, 750 and 850 ° C for 50 hours were evaluated. Results shows, the stellit6 / %10wt. Cr2O3 coating has the lowest oxidation rate. On the other hand, this coating shows the higher hardness other than non-reinforcement coating. The phase analysis investigation shows that the Cr2O3 oxide layer is forms during oxidation process on the surface of coatings. Its shows the Cr2O3 reinforcement is preferred areas for chromium oxides in thermal grown oxide (TGO) during oxidation Manuscript profile -
Open Access Article
25 - Modelling of austenite formation in weld heat affected zone of API-X65 and X70 pipeline steels
Jaafar Ahmadi rad Gholamreza KhalajIn the present work the two microalloyed steel (X65 and X70 ) used in oil and gas transition pipeline, was obtained as a hot rolled plate with accelerated cooling. First, weld heat affected zone thermal cycles, according to four-wire tandem submerged arc welding process MoreIn the present work the two microalloyed steel (X65 and X70 ) used in oil and gas transition pipeline, was obtained as a hot rolled plate with accelerated cooling. First, weld heat affected zone thermal cycles, according to four-wire tandem submerged arc welding process were analyzed. The Baehr 805A/D dilatometer was used for weld heat affected zone thermal cycles’ simulation. The thermal cycles simulated process for heated region involved heating the steel specimens to the peak temperatures of 950, 1150 and 1350 °C and transformation behaviour and microstructure is investigated. By analyzing the dilatometry results, continuous heating diagram, austenite grain growth and austenite formation kinetics were investigated. Austenite formation modeling was done using Johnson- Mehl- Avrami- Kolmogorov (JMAK) classic equation. The parameter n was found to be relatively independent on temperature (or heating rate); While the parameter k is strongly dependent to temperature, phase fraction transformed and austenite grain growth Manuscript profile -
Open Access Article
26 - Synthesis and Characterization of SrFe12O19/SiO2/TiO2 Composite Powder with Core/Shell/Shell Nanostructure
fatemeh bavarsiha Mehdi Montazeri-Pour Masoud Rajabi samira Gholami Naeimeh MozaffariIn this research study, the coating of titania particles on the SrFe12O19/SiO2 composite was successfully accomplished by the sol-gel process. For this purpose, first, the strontium hexaferrite particles were prepared by co-precipitation route with Fe3+/Sr2+ molar ratio MoreIn this research study, the coating of titania particles on the SrFe12O19/SiO2 composite was successfully accomplished by the sol-gel process. For this purpose, first, the strontium hexaferrite particles were prepared by co-precipitation route with Fe3+/Sr2+ molar ratios of 11 and 12 and subsequent calcination treatment. The formation of single phase strontium hexaferrite particles, as hard magnetic cores of the composite, was attained in the molar ratio of Fe3+/Sr2+=12 after calcination at 950 °C. In the next step, the silica coating of hexaferrite particles was performed using the tetraethyl orthosilicate (TEOS) precursor via the Stöber method. In the end, the covering of titania particles on the SrFe12O19/SiO2 composite was carried out by utilizing titanium n-butoxide (TNBT) precursor. The as-prepared composites were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy dispersive X-ray (EDX) and vibrating sample magnetometry (VSM) analyses. The results confirmed the core/shell/shell structure of the synthesized SrFe12O19/SiO2/TiO2 composite. The analysis of the magnetic properties showed that saturation magnetization (Ms) of strontium hexaferrite powder was obtained as 58 emu/g. After the successive coating of SiO2 and TiO2 shells, this amount has reached to 56 emu/g and 37 emu/g, respectively. Manuscript profile -
Open Access Article
27 - Synthesis of Molybdenum disulfide solid lubricant coating on steel using Thermal-diffusion method
mehdi akbarzadeh Morteza ZanrahimiMolybdenum disulfide (MoS2) is one of the most solid lubricants applied on surfaces under friction condition in different ways. In this study, MoS2 coatings was applied on 316 stainless steel using thermal diffusion method at various temperatures and times. Coatings pro MoreMolybdenum disulfide (MoS2) is one of the most solid lubricants applied on surfaces under friction condition in different ways. In this study, MoS2 coatings was applied on 316 stainless steel using thermal diffusion method at various temperatures and times. Coatings properties were investigated using SEM, EDX, XRD and FTIR, Hardness Tester and Roughness tester. The results indicated formation of a uniform layer on the surface that contains MoS2 and MoO3-X phases. Coatings have thickness of 20-50 µm and grain size of 400-1000 nm and hardness of 350- 550 HV. Also in this study, the kinetics of diffusion layer between substrate and coating has been investigated. the kinetics of diffusion layer between substrate and coating has been investigated. It was found that thickness of diffusion layer changes with time at constant temperature follow from parabolic equation.The thickness of diffusion layer changes with time at at constant temperature follow from parabolic equation. Manuscript profile -
Open Access Article
28 - Effect of Shoulder Surface Angle of Tool on Joint Properties in Friction Stir Welding of 5052 Aluminium Alloy
فرهاد غرویFriction stir lap welding of 5052 aluminum alloy was performed in the present research, and lap joints were fabricated by rotational speed of 1450 rpm and welding speed of 63 mm/min. Three tools with different shoulder surface angle (i.e. 0, 5, and 10 degrees) were desi MoreFriction stir lap welding of 5052 aluminum alloy was performed in the present research, and lap joints were fabricated by rotational speed of 1450 rpm and welding speed of 63 mm/min. Three tools with different shoulder surface angle (i.e. 0, 5, and 10 degrees) were designed and used. The effect of shoulder surface angle on joint properties was studied by optical microscopy and tensile-shear test. The results showed that only at angle of shoulder surface of zero-degree a continuous channel-like void was formed in the advancing side near the nugget zone and extended along the welding direction. The lap joints with the highest fracture strength has the smallest hook size, and is fractured at fraying surface rather than in the hook defect during tensile-shear test. Hook size and effective plate thickness (EPT) decreased from 4.5 to 2 and 2.25 to 1, respectively, as the angle of shoulder surface increased while the highest tensile-shear properties were obtained around 4650 N/mm at angle of shoulder surface of 10 degrees. Manuscript profile -
Open Access Article
29 - Repair of Structural Steel Surface Groove by Using Spray Welding and Diffusion Welding Methods
سید ابراهیم وحدت یونس رحیمی پدرام کیهانیTo improve mechanical properties and increasing useful life of metal parts, different methods of welding are used for repairing surface crack of metal parts. In this research, performance of flame welding by spraying pure iron powder and diffusion welding of pure iron p MoreTo improve mechanical properties and increasing useful life of metal parts, different methods of welding are used for repairing surface crack of metal parts. In this research, performance of flame welding by spraying pure iron powder and diffusion welding of pure iron powder through magnetic induction evaluated for repairing surface cracks of structural steel. First, eight specimens prepared including two control specimen and other six specimens grooved specimens in depth of 1mm and in length of 12.5mm and groove width in the sizes of 0.5, 0.75 and 1mm. then, two methods of repairing had done. Results showed that after repairing surface groove by using flame welding method and diffusion welding method, tensile strength of the repaired specimens reached to the tensile strength of control specimen with the margin of 2.5% and 7.5%, respectively. Therefore, flame welding method was safer than diffusion welding method for repairing surface groove of structural steel by using pure iron powder. Manuscript profile -
Open Access Article
30 - Fabrication of YSZ/Al composite coating on Incoloy 825 superalloy using electrophoretic deposition
mojtaba ahmadi Hossein AghajnaiAbstract In this research, Fabrication of YSZ/Al composite coating on Incoloy 825 superalloy using electrophoretic deposition has been investigated. Dispersion of YSZ and Al particles suspension in acetone in presence of iodine, as dispersant, was studied by particle si MoreAbstract In this research, Fabrication of YSZ/Al composite coating on Incoloy 825 superalloy using electrophoretic deposition has been investigated. Dispersion of YSZ and Al particles suspension in acetone in presence of iodine, as dispersant, was studied by particle size and zeta potential measurement. According to the results, the suspension containing 1.2 g/l iodine has been chosen for electrophoretic co-deposition of YSZ and Al particles. Mean diameter of YSZ and Al particles in this suspension was measured 111.6 nm and 2.658 μm and zeta potential value of these particles was measured 50.2 and 16 mV, respectively. In order to investigate the influence of applied voltage and deposition time on quality of formed deposit, electrophoretic co-deposition has been carried out at different voltages and deposition times. Results revealed that the deposit formed at voltage of 6 V and deposition time of 3 min had uniform and crack-free surface. SEM image showed that this coating had thickness of 19.63 μm. Manuscript profile -
Open Access Article
31 - Fabrication and characterization of ribbon and powder of amorphous alloy MBF-100 used in super alloy FSX- 414 TLP bonding
Mohamad Rajabi رضا بختیاریIn this research, the process of TLP joint for super alloy FSX-414 by using the interface layer of MBF-100 as ribbon or powder have been studied. For this purpose, two samples of cobalt base alloy super clubs FSX-414 with dimensions of 10 mm for connecting sample MoreIn this research, the process of TLP joint for super alloy FSX-414 by using the interface layer of MBF-100 as ribbon or powder have been studied. For this purpose, two samples of cobalt base alloy super clubs FSX-414 with dimensions of 10 mm for connecting sample with MBF ribbon & the other with the same dimensions with U&V shape track for connecting with powder have been done. In the following, both samples were subjected to a heat treatment cycle at temperature of 1175 degree of centigrade for 30 minutes’ microstructure of TLP connection area was investigated by using light microscope, scanning electronical microscope & EDS analysis, EDS map analysis & micro hardness. In microscopic pictures related to TLP bonding with ribbon & sample of powder of fuzzy areas, including the area under fuzzing & influenced area were specified completely. The result of EDS analysis & EDS map analysis & micro hardness of penetration capability& better connecting of ribbon rather than powder has been valided Manuscript profile -
Open Access Article
32 - Investigation of the effect of substrate on formation of chromium- and vanadium carbide coatings by thermal reactive diffusion
علی اکبر قادی حسن ثقفیان Mansour SoltaniehIn this research, the effect of substrate on the formation of chromium- and vanadium carbide coating was studied by thermal reactive diffusion. The substrate of H13 steel was coated in two kinds of metal and oxide bath with molar ratio of Cr/V=3 for 14 hour at 1000˚C. C MoreIn this research, the effect of substrate on the formation of chromium- and vanadium carbide coating was studied by thermal reactive diffusion. The substrate of H13 steel was coated in two kinds of metal and oxide bath with molar ratio of Cr/V=3 for 14 hour at 1000˚C. Carbide coatings including chromium carbide (Cr3C2, Cr7C3), vanadium carbide (V8C7) and the complex carbide phase of Cr2VC2 were formed on H13 steel. The thickness of the carbide coating was 8.5±0.5 µm and 6.5±0.5 µm, respectively in metal bath and oxide bath. The amount of vanadium- to chromium- rich regions in the carbide coating was less than the ratio of vanadium to chromium content in the metal bath. The results of coating in the present study was compared to the results of coating in a similar condition on Ck45 steel. The type of substrate had an important role on the coating thickness and the phase distribution of vanadium- and chromium- rich regions. However, the element distribution in the coating was not affected by the kind of substrate. Manuscript profile -
Open Access Article
33 - Precipitation synthesis and luminescence properties of MgAl2O4 nanoparticles doped with samarium
مژده ملک پور جرقویه سید علی حسن زاده تبریزی علی صفارA surfactant assisted Co-Precipitation method was employed for the synthesis of magnesium aluminate spinel with nanocrystalline size and high specific surface area. Calcination operations were performed in 800-1000° C for two hours. Different percentages of samarium MoreA surfactant assisted Co-Precipitation method was employed for the synthesis of magnesium aluminate spinel with nanocrystalline size and high specific surface area. Calcination operations were performed in 800-1000° C for two hours. Different percentages of samarium were doped to magnesium aluminate spinel to examine the properties of magnesium aluminate spinel. The prepared samples were characterized by thermal gravimetric and differential thermal gravimetric analyses (TG/DTA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Transmission electron microscopy (TEM), and photoluminescence spectrum (PL). XRD results showed that nanocrystals of magnesium aluminate spinel were influenced by the type of surfactant in 800° C. The results of luminescence spectrum show that by increasing the amount of samarium after 0.15 of weight percentage, concentration suppression happens and reduces the intensity of luminescence properties. Manuscript profile -
Open Access Article
34 - Low Temperature CO Sensor Based on PEDOT:PSS/Fe(II)(salen) Composite Thin Film
فرخنده عربلو نره یی Raheleh Memarzadeh Farhad Panahi Mohammad Davazdah Emami Sirus Javadpour Mohammad Hossein ShariatGas sensors are now widely used for routine monitoring of the quality of atmospheres. A sensitive PEDOT:PSS/Fe(salen) thin film based toxic gas sensor deposited on glass pieces with interdigitated Au electrodes was developed by the spin coating method. The obtained comp MoreGas sensors are now widely used for routine monitoring of the quality of atmospheres. A sensitive PEDOT:PSS/Fe(salen) thin film based toxic gas sensor deposited on glass pieces with interdigitated Au electrodes was developed by the spin coating method. The obtained composite was well characterized by different techniques such as UV–vis spectroscopy and FTIR. Also, the surface topography of thin film composite was investigated using AFM. The Fe(salen)-doped PEDOT:PSS on interdigitated electrode was experienced an immediate decrease in resistance when exposed to carbon monoxide gas under normal dry room temperature conditions (%RH=20). The results showed that the response of desired sensor was not unidirectional, and reverses to the original resistance level when CO was removed from the test chamber (RD< 2%). The highest response factor and lowest response time (t90) obtained were equal to 40±0.77% and 38s, respectively. Ultimately, the optimum level of doping (0.02 wt. % of Fe(salen)) was determined. Manuscript profile -
Open Access Article
35 - The effect of surface roughness and the current on the strength of stud welded pin
محمد خدائی جواد مختاریFast pin connecting to the steel parts to fasten cables and wires to the pipelines, anchors inside the cements to the steels structures and bolts inside the tanks is possible just using stud welding method. In this method an electric arc is established between pin and b MoreFast pin connecting to the steel parts to fasten cables and wires to the pipelines, anchors inside the cements to the steels structures and bolts inside the tanks is possible just using stud welding method. In this method an electric arc is established between pin and base metal, and partially melt their surfaces, then by applying a pressure, pin and base metal will be jointed. Some parameters such as surface roughness, time of electric arc, the thickness of base metal and current, affect the quality of stud welding. In this research, steel pins are connected to a steel base metal at three different surface roughness and three different current using stud welding method. Results of scanning electron microscopy (SEM) indicates that when the surface of base metal is rough, the interface of joint increases from 50 to 95 percent by increasing the current from 160 to 200 ampere. But that when the surface of base metal is smooth, the interface of joint between pin and base metal decreases from 95 to 50 percent by increasing the current from 160 to 200 ampere. Also the interface of pin and base metal solidify in martensitic form, and the results of microhardness measurement confirms the higher harness of the interface regarding base metal and pin. According to the results of tension test, the maximum strength (400 MPa) was related to the P60-200A sample. Manuscript profile -
Open Access Article
36 - Investigation of Microstructure, Hardness and Intermetallic Compound in Friction stir Welding of AA6065 Aluminum Alloy to Copper
مجید الیاسی Rahim Narimani Mortza Hosseinzadeh Hamed Aghajani DerazkolaIn this study, metallurgical properties lap joint of pure copper and 6065 aluminum alloy with friction stir welding technique were investigated. To purpose the metallurgical properties of joint optical microscopy, X-ray diffraction analysis (XRD), energy dispersive X-ra MoreIn this study, metallurgical properties lap joint of pure copper and 6065 aluminum alloy with friction stir welding technique were investigated. To purpose the metallurgical properties of joint optical microscopy, X-ray diffraction analysis (XRD), energy dispersive X-ray (EDS) and Vickers hardness junction of micro gauge were used. The results shows that due to the direct contact between aluminum alloy and tool shoulder, the microstructure change of AA6065 was more than copper. With increasing tool rotation speed the microstructure size of AA6065 and copper became smaller and with increasing linear speed and cooling rate, the microstructure size of base material became more. The results shows that the structured layers were formed in stir zone which with increasing heat generation they geometry became thinner and stretcher. The combination of base materials in high tool rotation and low travelling speed caused the CuAl2 and Cu9Al4 intermetallic compounds were formed in base metal interface. For changes in microstructure size and formation of intermetallic compounds, the hardness of stir zone was more than other area of joint. The maximum hardness of joint area was 111 Vickers which allocated to the joint that welded with 1130 rpm and 24mm/min tool speed. Manuscript profile -
Open Access Article
37 - Influence of the electrode distance and applied electrical potential on deposition of nano alumina in ethanol suspension
Mostafa Milani Syed Mohammad Zahraee Syed Mohammad MirkazemiThe kinetics of electrophoretic deposition is influenced by various factors. Hamakr summarized them on five parameters such as suspension concentration, electric field on the suspension, the surface area of the electrodes, electrophoretic mobility, and the process time. MoreThe kinetics of electrophoretic deposition is influenced by various factors. Hamakr summarized them on five parameters such as suspension concentration, electric field on the suspension, the surface area of the electrodes, electrophoretic mobility, and the process time. The electric field in the suspension can be changed using the electric potential applied between the electrodes and electrode distance change. Since the suspensions is a non-ohmic resistance, these two parameters will not be the same. The change of electric field using each of these two parameters causes kinetic equations change. In long distances electrodes and poor electrical potential, kinetic equations are based on electrical resistance more accurately. In the strong fields and low electrode distance kinetic equations based on equivalent conductivity are more accurate. The results of this study showed that, in the electric field 70V/cm Ferrari et al. equation and in the electric field 25V/cm Sarkar and Nicholson equation have accuracy of less than 0.01 and less than 0.1, respectively. Manuscript profile -
Open Access Article
38 - Synthesis of Graphene by laser method for using in electrochemical capacitors
shahab khameneh asl Majed NamdarIn this research work, laser scribed technique has been regarded to synthesize graphene on the surface of a DVD and manufacture graphene super capacitors. For this purpose, first, by Hummers method, graphite was converted to graphene oxide (GO) in an acidic environment MoreIn this research work, laser scribed technique has been regarded to synthesize graphene on the surface of a DVD and manufacture graphene super capacitors. For this purpose, first, by Hummers method, graphite was converted to graphene oxide (GO) in an acidic environment containing Sodium nitrate, Potassium permanganate and sulfuric acid. Centrifuges and ultrasonic devices were utilized for the homogenization of graphene oxide solution. GO homogeneous solution was applied on the surface of specific DVDs and the set was dried at room temperature. For GO reduction and transform it into graphene, a suitable laser, with programming of super capacitor particular pattern was used. By applying an energy with the amount of resonance frequency of graphene and oxygen bond, the laser broke the connection and the reduction action and reaching to graphene was done. In this study, the process of graphene synthesis and applying the super capacitor specific pattern were carried out in single step that is the biggest advantage of laser scribed graphene (LSG) method. In present study, TEM was utilized to examine the layered structure of GO, SEM was used for microstructural studies, two tests of cyclic voltammetry (CV) and galvanostatic charge/discharge (CC) were applied to study the performance and power of energy storage in super capacitors, the XPS was used to investigate elements present in the layer applied on DVD, and the Raman spectroscopy was applied to investigate the quality of prepared graphene through studying G and D peaks. Manuscript profile -
Open Access Article
39 - Efect of temperature on microstructure and intermetallic compound formation of Diffusion Bonded Mg/Al joints
Mohammad Ammar Mofid Mostafa Hajian Heidary Ehsan Loryaei Hatef ShakeriThe diffusion bonding of two dissimilar alloys Al 5083 and Mg AZ31 was carried out at 420,430.440 and 450 °C for bonding time of 60 min. In order to characterize the microstructure evolution in the joint zone, scanning electron microscopy (SEM), energy dispersive sp MoreThe diffusion bonding of two dissimilar alloys Al 5083 and Mg AZ31 was carried out at 420,430.440 and 450 °C for bonding time of 60 min. In order to characterize the microstructure evolution in the joint zone, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) were applied. The results show that joint formation is attributed to the solid-state diffusion of Mg and Al into Al 5083 and Mg AZ31 alloys followed by eutectic formation and constitutional liquation along the interface. At bonding temperature of 430°C diffusion induced grain coarsening was observed at the interface. With increase in bonding temperature, the atomic diffusivity increases, results in easier and speeder chemical bonding. In bonding temperature of 440°C the weld had an irregular shaped region in the weld center, having a different microstructure from the two base materials. The irregular shaped region contained a large volume of intermetallic compound Al12Mg17 and showed significantly higher hardness in the weld center. The present study suggests that constitutional liquation resulted in the intermetallic compound Al12Mg17 in the weld center. Manuscript profile -
Open Access Article
40 - Investigation of 6061 aluminum alloy pulsed laser welding based on the physical models for prediction of hot cracks
hossain ebrahimzadeh hassan farhangi seyed ali asghar akbari mousaviIt is necessary to use a physical model for the relationship between welding parameters and hot cracks. These models are available in micro, meso, and macro-scale. In this research, a sheet of 6061 aluminum alloy was welded by a Nd:YAG laser machine. For the first time, MoreIt is necessary to use a physical model for the relationship between welding parameters and hot cracks. These models are available in micro, meso, and macro-scale. In this research, a sheet of 6061 aluminum alloy was welded by a Nd:YAG laser machine. For the first time, the diameter of the dendritic arm spacing in the aluminum laser weld was measured and the results were compared with the solidification models. Contrary to the prediction of hot crack models, increasing the dendritic arm spacing, decreasing the solidification rate, and the reduction of the strain rate did not reduce hot cracking. However, based on the pre-existing models, preheating should reduce hot cracks, but inversely increases the amount of cracks. The images of high speed cameras and the assessment of crack surface by a field emission scanning electron microscopy showed that in pulsed laser welding, hot cracks will be created in three steps: 1) initiation 2) the first step of propagation 3) the second step of propagation. Propagation in the second step will occur in the newly solidified weak grain boundary of the weld metal. What is finally seen as a crack in the weld seam is the solidification and high temperature cracks and therefore, the models that are considered for continuous fusion welding are required to be modified based on the conditions of the pulsed solidification and melting and the fracture of weak grain boundaries after solidification should also be taken into account. Manuscript profile -
Open Access Article
41 - Investigation of Electrochemical and Mechanical Properties of Solid Oxide Fuel Cell Fabrication by 3d Printer
keyvan mirzaei feshalami zahra sadeghiyan Ramin EbrahimiNowadays, various methods have been introduced for the fabrication of solid oxide fuel cells (SOFC). In this research, 3D printing technology has been used to produce oxide fuel cells. First, a 3D printer was constructed that has the ability to print the MoreNowadays, various methods have been introduced for the fabrication of solid oxide fuel cells (SOFC). In this research, 3D printing technology has been used to produce oxide fuel cells. First, a 3D printer was constructed that has the ability to print the slurry of anode, cathode and electrolyte layers with the desired thickness and speed. Then a suitable slurry consisting of NiO-YSZ materials was produced for the anode layer, YSZ for the electrolyte layer and LSM for the cathode, with suitable solvents and additives. After cell formation, drying and then sintering of the layers were performed. The composition and microstructure characterization of layers has been performed by XRD, SEM, Mapping, EDS. The I-V-P curve showed the maximum power is around 0.84 W / cm2 at 800 OC with constant oxygen. The impedance curve values under open-circuit voltage were 0.23 Ωcm-2 and 1.25 Ωcm-2 at high and low frequencies, respectively. The tensile experiments indicated values 111 GPa for Young modulus and 137 MPa and 120 MPa values for the fracture toughness and the yield strength, respectively. Manuscript profile -
Open Access Article
42 - Friction Stir Welding of Ultrafine-Grained Al 1050: Investigation of Pin Geometry, Welding Atmosphere Temperature and Welding Speeds on the Mechanical Properties
Morteza Hosseini Habib Danesh-ManeshThe application of ultrafine-grained or nanostructured aluminum is very interesting owing to its high strength to weight ratio. Welding of these materials is one of the main challenges. Regarding the potential of the solid-state friction stir welding in joining of nanos MoreThe application of ultrafine-grained or nanostructured aluminum is very interesting owing to its high strength to weight ratio. Welding of these materials is one of the main challenges. Regarding the potential of the solid-state friction stir welding in joining of nanostructured materials, in the current research different equipment and techniques like optical and scanning and transmitted electron microscopes, Vickers microhardness, and uniaxial tensile tests were employed to study the effect of major welding parameters on the bonding quality of friction stir welded ultrafine-grained Al 1050 alloy produced via accumulative roll-bonding (ARB) method. The studied parameters were rotation and traveling speeds, pin geometry as well as welding atmosphere temperature. The results show the microhardness enhancement of the weld zone by decreasing the rotation speed or increment of traveling speed due to lower heat generation within the stir zone. Investigation of the pin geometry depicts an insignificant impact of this variable on the weld tensile properties. Only in the case of a threaded pin, a slight enhancement in the tensile properties was achieved. Submerge or underwater welding could improve joint strength. However, the application of extremely cold water with respect to 25° C water shows a reverse effect and leads to severe weld quality degradation owing to defects formation (like internal channels and surface discontinuity). Manuscript profile -
Open Access Article
43 - Experimental Study an improvement of Parameters Affecting Resistance Spot Welding Strength in Halogen lamps by Taguchi Statistical Method
Lotfali Mozafari Vanani Sadegh RahmatiThe Resistance Spot Welding (RSW) has lots of industrial application, especially for body construction and some parts like car lamps. The aim of this research was optimizing of the production line efficiency and improving the welding strength of the car lamps. Experimen MoreThe Resistance Spot Welding (RSW) has lots of industrial application, especially for body construction and some parts like car lamps. The aim of this research was optimizing of the production line efficiency and improving the welding strength of the car lamps. Experimental studies were conducted on the factors affecting the weld strength in a H4 halogen lamp (wing to body connection). The experiments design and results analysis were done by Taguchi method and Minitab software. Welding current, welding time and electrode material were studied as main factors (inputs) in the actual lamp samples. Experimental results and statistical analyzes indicated that the high dependence of welding strength on welding time is primarily and with a quantitative difference in the second order to the welding current. According to the results, it was found that with any kind of electrode material, if welding time and welding current increases to moderate, welding strength will be improved. But in high values of time and current, there is a negative effect on the welding strength. Although the welding electrode has the third highest rating on weld strength. But during the testing process and analyzing it was found that the efficiency of the lamp production line in the case of using tungsten electrodes in the significant amount of 29.17% compared to the electrodes of Copper is more. While the welding strength of the tungsten electrode is only 5.5% lower than the copper electrode. This strength is still within allowed and acceptable limits of the relevant standards. Manuscript profile -
Open Access Article
44 - Pulsed laser surface melting of AISI H13 steel and investigating the effect of TiC powder particle size and concentration on the morphology of MC carbides in the composite coating
محمدعلی بوترابی Ali Dadoo Shahram KheirandishIn this research, the microstructure of the pulsed laser surface melted AISI H13 tool steel was studied. Then, by laser surface alloying with TiC powder, the effect of particle size and powder concentration on superficial composite microstructure was investigated. For t MoreIn this research, the microstructure of the pulsed laser surface melted AISI H13 tool steel was studied. Then, by laser surface alloying with TiC powder, the effect of particle size and powder concentration on superficial composite microstructure was investigated. For this purpose, TiC powders with particle sizes of 1 micrometer and 45 micrometers in layers of different thicknesses were pre-placed on the surface of H13 steel and then subjected to pulsed laser operation. The results showed that in the surface melting, an intermittent cell/dendritic structure developed from the depth to the surface of the molten pool with a higher concentration of alloying elements in the boundary network. With the selected laser parameters, the cooling rate was estimated at one million K/s. In the surface alloying process, the preplaced TiC particles were completely (fine powders) or a partially (coarse powders) dissolved in the melt pool. During subsequent cooling, TiC-type MC carbides precipitated from the melt. Increasing the thickness of the preplaced layer caused the morphology of carbides to be more diverse. The size of precipitated MC carbides was reduced by decreasing the concentration of TiC powder in the melt pool and increasing the particle size of preplaced TiC powder. As the number of MC carbides increased, the cellular/dendritic structures of the steel matrix replaced by coaxial grains. Manuscript profile -
Open Access Article
45 - Electrical Discharge Machining of Aluminum Matrix Composite Reinforced With Titanium Oxide Nano-Particles
Ali akbar lotfi Saeed Daneshmand.Nano-particles used in metal matrix composites show a various range of mechanical, chemical and physical features, causing significant improvements in mechanical strength, hardness and thermal characteristics. They can also change the capability of machining. Electrica More.Nano-particles used in metal matrix composites show a various range of mechanical, chemical and physical features, causing significant improvements in mechanical strength, hardness and thermal characteristics. They can also change the capability of machining. Electrical discharge machining is considered as an integrate part of hard metal machining. In this paper, the parameters of electrical discharge machining for aluminum composite material improved by Nano-particles of titanium dioxide have been studied. The purpose of this study was to evaluate the impacts of electrical current and voltage and pulse on and off-time on the material removal rate, tool wear rate and surface roughness. Kerosene as a dielectric and copper electrode were used to carry out the experiment. In addition, Analysis of variance was utilized to authenticate the experimental results. The result shows that Nano-particles titanium dioxide has trivial effects on machining parameters due to being insulators. They also do not melt in the process of electrical discharge machining. Moreover, the electrical current and the pulse on time have the most influence on the material removal rate, tool wear rate and surface roughness. By increasing the electrical current and pulse on time, tool wear rate and surface roughness have grown, while by increasing the pulse off time tool wear rate has decreased. The average wear rate of the electrode in the aluminum alloy 2024 reinforced with 5% titanium oxide nanoparticles is 46.3%, equivalent to 0.346 gr, more than the weight loss of the aluminum 2024 specimen. Manuscript profile -
Open Access Article
46 - Investigation on performance of polyurethane by adding of Titanium dioxide Nanoparticle.
صاحبعلی منافی Mehdi TalaeeDispersion of nanotitan particles in polyurethane (PU) resin plays an important role to achievement better mechanical and physical properties. In this study nanocomposite coating was performed by incorporating nanotitania pigment with rutile and anatase phase in polyure MoreDispersion of nanotitan particles in polyurethane (PU) resin plays an important role to achievement better mechanical and physical properties. In this study nanocomposite coating was performed by incorporating nanotitania pigment with rutile and anatase phase in polyurethane to different loading level (0.1, 0.5, 1.0 and 2.0% by weight). Dispersion of nanoparticles in PU matrix was done by using ultrasonication mixing machine (2 h) and rotary mixer (3 h) and also again UT mixing machine (1 h) and finally gas removing. After addition of the appropriate amount of hardener, prepared nanocomposite coating was investigated by applying on steel and glass substrate and after 2weeks time for curing, exposing them to UV weathering, salt spray, scratch and hardness testing. The dispersion quality and surface morphology of nanocomposite coating was evaluated by using different analytical techniques. Dispersion quality of nanocomposite was investigated using optical microscopy. Dry film thickness (DFT) of samples was mostly in the range 90 µm. Roughness after exposing of naoncomposites on UV radiation and salt spray measurement by atomic force microscopy (AFM) topography and analysis by this apparatus and mechanical behavior also by using hardness and scratch test and also by colorimetry measurements, surface degradation of PU nanocomposite coatings was characterized by color changing, defined as the color measurement, after being exposed to accelerated weathering conditions. Manuscript profile -
Open Access Article
47 - Substitution of Zinc Cation in Nickel Ferrite Synthesized by Sol-Gel Method and Evaluation of its Effect on Microwave Absorption, Structural and Magnetic Properties
Shirin Tahmasebi Reza Ebrahimi-Kahrizsangi Ali Ghasemi Ebrahim GhasemiIn this study were examined the effect of adding zinc cation instead nickel cation on the structural and magnetic properties of nickel ferrite prepared by sol-gel method. X-ray diffraction, field emission scanning electron microscopy, energy resolution spectroscopy, Fou MoreIn this study were examined the effect of adding zinc cation instead nickel cation on the structural and magnetic properties of nickel ferrite prepared by sol-gel method. X-ray diffraction, field emission scanning electron microscopy, energy resolution spectroscopy, Fourier transform infrared spectroscopy, vibrating sample Magnetometer and vector analysis network device produced were used to verify the structural characteristics and magnetic ferrite particles. Single temperature recognized for nickel ferrite doped with zinc ions, 1200oC.For samples the doped ferrite phase and the second phase was achieved without any impurities. Scanning electron microscopy images showed obtained by particle size increases with increasing substitution of cation zinc. Breakdown spectroscopy graphs showed substituted increase energy and reduce peak of cation zinc peak size by increasing the nickel of cation. Fourier transform infrared charts compounds to confirm the results of X-ray diffraction patterns indicate the phase formation and placement of metal cations in spinel structure. Magnetic hysteresis curves, respectively increasing the saturation magnetization and the residual magnetization to combine x=0.6 and then reduce them to combine x=1. Waste dehydrogenation magnetic have consistently decreasing trend until combined x=0.8 and then will combined x=1. With zinc substitution increased reflection loss. Zinc cation by nickel ones, causes improving of the magnetic properties and microwave absorbtion and this material could be used for the different applications such as microwave absorbance. Manuscript profile -
Open Access Article
48 - Improvement of Load Bearing Capacity of Al-1100 Joining area by using In-situ Synthesizing of Al/Cr during FSSW
سعید مطلبی فشارکی مسعود مصلایی پور علیرضا مشرقی سید صادق قاسمیIn-situ synthesizing of Al/Cr was carried out to improve the strength of spot joining of Al plates. For this purpose, 0.03gr Cr powder with 10 μm particle size was inserted in the spot joining zone and the assembly was subjected to the Friction Stir Spot Welding Proc MoreIn-situ synthesizing of Al/Cr was carried out to improve the strength of spot joining of Al plates. For this purpose, 0.03gr Cr powder with 10 μm particle size was inserted in the spot joining zone and the assembly was subjected to the Friction Stir Spot Welding Process (FSSW). Microstructure, formation of intermetallic compounds and mechanical properties of samples were investigated by optical microscopy (OM), scanning electron microscopy with spot and line EDS, tensile and microhardness measurements. Spot and line scan chemical analysis (Spot-EDS and Line-EDS) of joining area indicated that minimal tool rotation speed for formation of Al-Cr intermetallic compounds (Al13Cr2) is around 2500 rpm. Formation of Al-Cr rich intermetallic compounds in the joining area increased the hardness of joining zone more than two times of hardness of join without this components (140±5 HV and 60±5 HV). Furthermore, in-situ synthesis joining increase ultimate tensile strength of the joint from 40±5 Mpa to 130±10 Mpa Manuscript profile -
Open Access Article
49 - Fabrication of Nanofibers Core - Shell Oxide by One Step Electrospinning Method
حجت رفیعی پور محمد رضا واعظی اصغر کاظم زادهIn this paper, core - shell nanofibers were synthesized by single stage electrospinning. To achieve on this aim, a coaxial needle was used, and oxides precursor were solved in polyvinyl alcohol (PVA) solution, and injected by separate syringes which connected to one pum MoreIn this paper, core - shell nanofibers were synthesized by single stage electrospinning. To achieve on this aim, a coaxial needle was used, and oxides precursor were solved in polyvinyl alcohol (PVA) solution, and injected by separate syringes which connected to one pump. Calcination was done on synthsised core – shell nanofibers. The morphology and microstructure of nanofibers were examined by field emission scanning electron microscope (FE-SEM), transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The final structure is ZnO as shell and SnO2 as core. The core diameter and the shell thickness nanofiber from TEM image are approximately 45 nm and 25 nm, respectively. The average diameters of as-electrospun and calcined core - shell nanofibers are about 175 and 79 nm, respectively. Manuscript profile -
Open Access Article
50 - Investigation of the Ways of Purification of Apatite Stone and Its using in the Ceramic Glazes
Davoud Ghahremani صاحبعلی منافی E. فرح بخش Fariborz ForohandehIn the current research, within purification of apatite stone of Bafg investigated its using in the formulation of white glaze of Single firing of fast fired Wall Tile (Monoporosa Tile). The results of the investigations done on the purificated apatite of Bafg determine MoreIn the current research, within purification of apatite stone of Bafg investigated its using in the formulation of white glaze of Single firing of fast fired Wall Tile (Monoporosa Tile). The results of the investigations done on the purificated apatite of Bafg determined that this matter showing good thermal stability under the temperature of 1400 degress centigerate and isn’t any unfavorabale element in its compositon for using in ceramic glaze formulations exception of iron. Nevereless the problem of low Thermal Expansion Coefficient of the white glazes of Monoporosa, The Dilatometry results of the glaze containing Apatite dictated higher Thermal Expansion Coefficient. The images of SEM showed both the safe adhering of glaze to engobe and increment of amount of insoluble fine particles of zircon in the base phase of glaze that with the safe results of colourimetry was the explanatory of increment of the whitness of current glaze. Also by considering the low price of this matter, it wills reduce the final price of glaze. Manuscript profile -
Open Access Article
51 - Fracture toughness and plasticity evaluation of sputter deposited tantalum nitride thin film
Siavash Firouzabadi Kamran Dehghani Malek Naderi Farzad MahboubiAlthough tantalum nitride coatings have recently been attracted researchers’ attentions due to their high hardness and corrosion resistance, the fracture toughness and deformation plasticity of thin tantalum nitride film has not been well investigated yet. In this MoreAlthough tantalum nitride coatings have recently been attracted researchers’ attentions due to their high hardness and corrosion resistance, the fracture toughness and deformation plasticity of thin tantalum nitride film has not been well investigated yet. In this research, for the first time, the fracture toughness, strain rate sensitivity and plasticity of sputter deposited tantalum nitride thin films have been evaluated using nano indentation technique and SEM micrographs. It was shown that the fracture toughness was increases from 0.6 to 7.8 MPa√m with increasing the nitrogen in sputtering chamber. This increase was attributed to the structural evolution from a hexagonal γ-Ta2N phase to the hexagonal ε-TaN and face centered cubic δ-TaN phases, determined by X-Ray Diffraction analysis. The plasticity of the TaN films evaluations indicated that the ratio of plastic work to total work was increased from 50% to 57% and 80%with phase variation from γ-Ta2N to ε-TaN and δ-TaN, respectively. Manuscript profile -
Open Access Article
52 - Investigation of the welding pass numbers on structure, hardness and wear resistance of sheet welded by ESAB 85.65
abbas saadat mohammad khalili parvar mohammad Reza khanzadeh ghareshiranدر این پژوهش یک لایه مقاوم به سایش توسط الکترود ESAB 85.65 ‏ برروی فولاد ساده کربنی ایجاد و اثر تعداد پاس بر ریزساختار، مقاومت سایشی و سختی بررسی گردید. آنالیز های SEM، XRD و سختی سنجی به منظور مشاهده ریزساختار، شناسایی نوع فازها، مورفولوژی رسوبات و سختی آن ها در من Moreدر این پژوهش یک لایه مقاوم به سایش توسط الکترود ESAB 85.65 ‏ برروی فولاد ساده کربنی ایجاد و اثر تعداد پاس بر ریزساختار، مقاومت سایشی و سختی بررسی گردید. آنالیز های SEM، XRD و سختی سنجی به منظور مشاهده ریزساختار، شناسایی نوع فازها، مورفولوژی رسوبات و سختی آن ها در منطقه جوش استفاده گردید. نتایج نشان داد که در ساختار نمونه‏های سخت کاری شده، فازهای کاربیدهای کمپلکس Fe2W2C و M6C ، فازهای فریت و آستنیت مشاهده می‏گردد. فاز کاربیدی Fe2W2C غنی از تنگستن و کربن بوده و به عنوان یک کاربید با سختی و مقاومت به سایش بالا شناخته می‏شود. همچنین با افزایش تعداد پاس‏های فرآیند، میزان سختی نمونه‏های سخت کاری افزایش یافته است به طوریکه نمونه حاصله از فرآیند سه پاس با میانگین سختی HRC59 نسبت به نمونه تک پاسHRC) 54)، سختی بهتری دارد. نتایج آزمون سایش نشان می‏دهد که کمترین کاهش وزن مربوط به نمونه‏ جوشکاری شده با سه پاس در دمای بالا می‏باشد. همچنین مشاهده می‏شود که با افزایش سختی، مقاومت به سایش نیز افزایش می‏یابد. Manuscript profile -
Open Access Article
53 - Investigating the sensing properties of SnO2-PdPt nanohybrid toward methane gas and effect of adding reduced graphene oxide on improving its sensing performance
Shiva Navazani Ali Shokuhfar Mostafa HassanisadiIn this paper, the sensing properties of SnO2-PdPt nanohybrid to methane gas and effect of reduced graphene oxide (rGO) on improving its sensing performance was investigated. For this reason, first SnO2 was synthesized by hydrothermal method and then hybridized by Pd, P MoreIn this paper, the sensing properties of SnO2-PdPt nanohybrid to methane gas and effect of reduced graphene oxide (rGO) on improving its sensing performance was investigated. For this reason, first SnO2 was synthesized by hydrothermal method and then hybridized by Pd, Pt and PdPt catalysts. For investigating the effect of rGO, by the in-situ hydrothermal method, SnO2-rGO was synthesized instead of SnO2. Results showed that the nanohybrid sensor with bimetallic alloy catalyst, had higher response t lower temperature compared with monometallic catalysts and on the other hand, adding rGO, reduced the optimum sensing temperature of SnO2-PdPt and enhanced its response to methane. The SnO2-PdPt nanosensor showed 52.22% response to 1000ppm CH4 at 200oC. The sensing response and recovery times for this hybrid were 94s and 3.5min respectively, whilst the SnO2-rGO-PdPt showed 69.5% response at 150oC to the same concentration of methane. The response and recovery times for this hybrid were 50s and 4.5min respectively. Manuscript profile -
Open Access Article
54 - Effect of activated carbon additive on microstructure and phase composition of reaction bonded boron carbide ceramic
Ahmad bayat Omid Mirzaee Hamidreza BaharvandiAbstract Boron carbide is highly regarded because of many properties such as high hardness, high Young’s modulus, low density and etc. however, application of B4C is rather limited due to difficulties in densification and low fracture toughness. In this research, MoreAbstract Boron carbide is highly regarded because of many properties such as high hardness, high Young’s modulus, low density and etc. however, application of B4C is rather limited due to difficulties in densification and low fracture toughness. In this research, uniaxial press at constant pressure of 140 MPa was applied to fabrication of boron carbide porous preforms. B4C powder with size of 43µm, activated carbon with the amount of 0,5,10 Wt.% and phenolic resin powder as a binder and Porosity-causing agent with the amount of 9 Wt.%, were used as raw materials. Infiltration operation with molten silicon had performed in vacuum furnace in temperature 1600 °C. β-SiC phase produced from silicon and carbon that caused the volume density and strength properties of specimens during infiltration process. Residual silicon was decreased from 35%.vol to 18 vol.% with increasing activated carbon contents, on the contrary, secondary silicon carbide had increasing continuously from 10%.vol to 2 vol.%. Decreasing in residual silicon and increasing in β-SiC phase determined by Image analysis software. Manuscript profile -
Open Access Article
55 - Aluminum alloy (АМГ6М) joining by two processes of friction-stir and non-consumable Tungsten electrode welding and comparison of their mechanical and microstructure properties
Aliasghar Torabi Tahmineh Ahmadi Afshin Shirali Mohammadreza Khanzadeh ghareshiran Majid TaghianThe purpose of this research is to investigate the possibility of replacement of arc welding under shielding gas with non-consumable Tungsten electrode (TIG) of Al АМГ6М alloy by friction stir welding (FSW). In this regard, after applying primary parameters for both wel MoreThe purpose of this research is to investigate the possibility of replacement of arc welding under shielding gas with non-consumable Tungsten electrode (TIG) of Al АМГ6М alloy by friction stir welding (FSW). In this regard, after applying primary parameters for both welding processes to obtain optimum parameters, the prepared samples were characterized with Tension, bending, radiography, hardness and distortion tests and also microstructure evaluation. The results of this study showed that the grain size of welding zone of TIG and FSW processes are 14 and 6 µm respectively, which are smaller than the base metal with 30 µm in size. The ultimate tensile strength of the FSW joints in the parallel to rolling direction and in the vertical direction with welding line is much more higher than TIG joints; 364 Mpa versus 278 Mpa. The reduction of microhardness in the welding zone for both process FSW and TIG have been in a range. The amount of distortion measured in the FSW was one-fourth of these values in TIG. The result of bending test of the FSW sample from the plane like to the results of the base metal is crack free. Therefore, in order to improve the mechanical and metallurgical properties, as well as to reduce weld joints distortion in aluminum structures, FSW was considered an appropriate alternative to the replacement of the arc welding under shielding gas with non-consumable tungsten electrode. Manuscript profile -
Open Access Article
56 - Phase transformations during high temperature brazing of dissimilar bonding of IN738 to TiAl intermetallic compound using Ni-Si-B ternary filler alloy
Dariush Kokabi Ali Kaflou Majid Pouranvari Reza GholamipourIn this research microstructural evolution during high temperature brazing of dissimilar bonding of IN738 Ni-base superalloy to TiAl intermetallic compound using an amorphous Ni-Si-B ternary alloy was investigated. Phase transformations via solidification and solid stat MoreIn this research microstructural evolution during high temperature brazing of dissimilar bonding of IN738 Ni-base superalloy to TiAl intermetallic compound using an amorphous Ni-Si-B ternary alloy was investigated. Phase transformations via solidification and solid state reactions are discussed. Observations indicated that the microstructure of IN738/MBF-30/TiAl joint consist of four different zones; isothermal solidification zone in both sides, athermally solidified zone in the bond center, diffusion affected zone in the IN738 side and reaction layer in the TiAl side. γ-Ni solid solution phase in ISZ of the IN738 side and binary isostructural solid solutions in ISZ of the TiAl side were formed during holding time at bonding temperature. Ni-Cr borides have been formed due to binary eutectics associated with γ-Ni solid solution in the ASZ during cooling. Cr-Mo borides and Ni-rich boride with different morphologies were precipitated in the DAZ. Ni element from MBF-30 molten interlayer reacted with γ-TiAl base, leading to the formation of the reaction layer containing single phase δ-Ti2Ni and triple phase τ2-Al2TiNi+τ4-AlNi2Ti+β1-NiAl layers adjacent to TiAl substrate. Microhardness evaluation of different zones indicated that some high hardness phases have formed in the bond region and presence of the γ-Ni solid solution in the ASZ cause to decrease the detrimental effects of them. Manuscript profile -
Open Access Article
57 - Nitrogen effect on the precipitation of secondary phases and mechanical property of the GTA welded Inconel 718
behrooz nabavi Massoud goodarzi AbdulKhaliq Khan ehsan ahmadiIn this research paper, principal attention is given to the effect of interstitial nitrogen on the precipitation of secondary phases and tensile strength of gas tungsten arc welded (GTAW) Inconel 718. Welding was performed using Ar+(0-5%)N2 shielding gas mixtures. Secon MoreIn this research paper, principal attention is given to the effect of interstitial nitrogen on the precipitation of secondary phases and tensile strength of gas tungsten arc welded (GTAW) Inconel 718. Welding was performed using Ar+(0-5%)N2 shielding gas mixtures. Secondary phases were characterized by optical microscope, field-emission gun scanning electron microscope (FE-SEM) and transmission electron microscope (TEM). The results revealed that with increment of nitrogen content, the volume fraction of Nb-bearing phases like Laves and carbide increased due to increased microsegregation of Nb in interdenderitic region. Moreover, nitrogen was found to have negative role in the size of gamma double prime particles within γ core. According to the tensile test results, Ar+1%N2 weld samples showed the maximum ultimate tensile strength and yield strength compared to other samples. While more nitrogen leads to reduction of both strengths due to increased Laves phase quantity and decreased size of gamma double prime precipitates. Manuscript profile -
Open Access Article
58 - The effect of Al2O3 Nano-particles coated with manganese oxide on the microstructure and mechanical properties of low carbon steel using GMAW process
farzad pahnaneh masood aghakhani farid naeimi , Moeen MansoubiThis paper reports an investigation carried out to determine the effect of aluminum oxide Nano-particles coated with manganese on the microstructure and mechanical properties of single-pass butt joint of low carbon steel plates of 6.0 mm thicknesses using gas metal arc MoreThis paper reports an investigation carried out to determine the effect of aluminum oxide Nano-particles coated with manganese on the microstructure and mechanical properties of single-pass butt joint of low carbon steel plates of 6.0 mm thicknesses using gas metal arc welding process. After selecting appropriate welding parameters and adding 0.25 gr and 0.5 gr of Nano-particles into the joint line and carrying out the welding, the samples were prepared for micro hardness and tensile tests. Furthermore, the sample with optimum Nano-particles having the highest ultimate tensile strength and without having any visible and metallurgical defects in the microstructure was selected for further investigation. Subsequently, microstructures of the weld without and with optimum Nano-particles were studied using optical microscopy and scanning electron microscopy (SEM) and the fractured surface of the weld obtained from tensile testing was investigated for the samples without Nano particles and the optimum sample with Nano materials were studied. The results show that Nano-particles added to the weld pool penetrated into the weld zone and helped in formation of acicular ferrite in the microstructure. Based on the results obtained, ultimate tensile strength and percentage of elongation of samples without Nano-particles and with optimum Nano-particles were increased from 387 MPa and 6.8% to 408 MPa and 13.6%, respectively. In addition, the average hardness of the weld metal without Nano-particles and with optimum Nano-particles were increased from 158 VHN to 172 VHN respectively Manuscript profile -
Open Access Article
59 - Modification of Microstructure and Enhancing Mechanical Properties of as-cast AZ91 Magnesium alloy via Friction Stir Processing
Hassan Jiryaei Sharahi Majid Pouranvari Mojtaba MovahediMagnesium alloys, as the lightest structural alloys, due to their high strength-to-weight ratio offer significant potential for improving energy efficiency of various transportation systems. This paper addresses the influence of friction stir processing (FSP) treatment MoreMagnesium alloys, as the lightest structural alloys, due to their high strength-to-weight ratio offer significant potential for improving energy efficiency of various transportation systems. This paper addresses the influence of friction stir processing (FSP) treatment on the microstructure and mechanical properties of cast AZ91 Mg alloy. It is demonstrated that FSP treatment enables elimination of dendritic structure, significant grain refining, break-up and partial dissolution of coarse β and formation of ultra-fine sub-micron Mg17Al12 particles. These microstructural modifications resulted in enhancement of mechanical properties in terms of tensile strength and energy absorption by 48% and 283%, respectively. It is shown that FSP treatment altered the failure mechanism of the alloy from brittle cleavage-dominant mode to ductile dimple-dominant mode which can increase the potential of Mg alloys to use in safety-critical application. Therefore, it can be concluded that FSP, as a process of sever plastic deformation at high temperature, has a great potential to tailor the microstructure and enhancing the mechanical properties of cast Mg alloys. Manuscript profile -
Open Access Article
60 - Effects of Heat Treatment on the Microstructure, Mechanical Properties and Corrosion Behavior of 2209 Duplex Stainless Steel Parts Manufactured By Wire Arc Additive Manufacturing Process
Ali A. Molazadeh Kashkouie Mahmood Sharifitabar Mahdi Shafiee AfaraniThe present study deals with the fabrication and investigation of structure, microstructure, mechanical properties and corrosion resistance of 2209 duplex stainless steel parts made by wire arc additive manufacturing method. The formation of ferrite and austenite phases MoreThe present study deals with the fabrication and investigation of structure, microstructure, mechanical properties and corrosion resistance of 2209 duplex stainless steel parts made by wire arc additive manufacturing method. The formation of ferrite and austenite phases was confirmed by XRD analysis. There was a non-uniform distribution of ferrite and austenite phases in the microstructure of the as-welded microstructure. The tensile and Vickers microhardness tests were employed to evaluate mechanical properties. The results showed that the mean values of yield and tensile strengths were respectively 2.7 and 5.5% higher and the elongation was 4.5% lower in the welding direction than the building direction. Post-processing heat treatment at 1000 °C for 30 min led to the grain refinement of the alloy, the formation of equiaxed microstructure, increase in the austenite volume fraction, and increasing the mean hardness from 318 to 376 HV. The fractography of the tensile test specimens revealed the ductile fracture mode in all samples. Corrosion test results showed that the heat treatment improved the corrosion resistance of the alloy. Manuscript profile -
Open Access Article
61 - Effect of Interlayer Type on Mechanical Properties and Microstructure of the 6061 Aluminum Alloy Joint by Friction Stir Welding
seyed amin kafaei Hamed Sabet Mohsen GhanbariIn the current research, the effect of Parameters on friction stir welding of aluminum 6061 metal is carried out using with and without an interlayer. After the welding process, microscopic tests, traction and microscopic examination were performed using optical microsc MoreIn the current research, the effect of Parameters on friction stir welding of aluminum 6061 metal is carried out using with and without an interlayer. After the welding process, microscopic tests, traction and microscopic examination were performed using optical microscope and scanning electron microscope. Among the welded samples with 4043, 5556, and 2024 aluminum interlayers and without interlayer, the welded specimen with a rotational speed of 1250 rpm and a linear velocity of 50 mm / min with an aluminum interlayer of 2024 has the highest tensile strength 192 MPa and has the most hardness of 154 Vickers. The minimum tensile strength of the welded specimen with the aluminum 4043 as an interlayer at the rotational speed of 800 rpm and the linear velocity of 31.5 mm / min is 166 MPa, and with 96 wickers, it also has the least hardness in the weld button in between All samples were. The microstructure study also showed the larger grain size in the welded samples with the interlayer and without interlayer, with a rotational to linear ratio of 32 rpm as compared to the rest of the specimens. The sample was welded to the aluminum with interlayer of 4043 at a speed of 800 rpm and a linear speed of 31.5 mm / min with the smallest grain size of 9 μm in the samples welded to the interlayer. The results of the tests show that the use of aluminum 5556 and 2024 as an interlayer improves the mechanical properties of the bonding zone. Manuscript profile -
Open Access Article
62 - Effect of Rotational Speed on Microstructure and Mechanical Properties of AA5456 Alloy Welded by FSW-Lap Joint
mohamad ali safarkhanianFriction stir welding process is solid state welding method that does not have many common defects in fusion methods. In this method for creating optimum weld, some parameters should be optimized, such as welding tool geometry, rotational speed and travel speed. The aim MoreFriction stir welding process is solid state welding method that does not have many common defects in fusion methods. In this method for creating optimum weld, some parameters should be optimized, such as welding tool geometry, rotational speed and travel speed. The aim of this study was to investigate the effect of rotational speed on microstructure and mechanical properties of friction stir lap welding AA5456 in rotary state to optimize the parameter values. For this purpose, Welding process was performed in rotating state, rotating tool was plunged from the cold-worked tube (AA 5456-H321 with 5 mm thickness) surface into the surface of Annealed tube (AA 5456-O with 2.5 mm thickness) and lap joints were produced by rotational speeds of 300, 500, 700 and 900 rpm and welding speed of 45 mm/min. Macro and microstructure of weld cross sections by optical microscopy (OM) and scanning electron microscopy (SEM) were studied. Then the hardness profile and tensile shear test were obtained and compared to another. Finally the fracture surfaces of some samples were examined by using a scanning electron microscope (SEM). The Macro and microstructure results show that increasing of rotation speed, increases the vertical flow of material, the height of hook as well as fine-grained sediments in the nugget zone. Increasing the rotational speed, decreases hardness of weld nugget. The results of tensile shear test show that the welding parameter of (700 rpm- 45 mm/min) is the optimal combination of parameters in this study. Manuscript profile -
Open Access Article
63 - Evolution of the Microstructure and Mechanical Properties of Friction Stir Welded Ferrite-Martensite DP700 Dual Phase Steel
Mahdi Mahmoudiniya Amir Hossein Kokabi Massoud goodarziIn present research, the effect of tool transverse speed on the microstructure and mechanical properties of friction stir welded DP700 dual-phase steel has been studied. Welding process conducted at a rotational speed of 800 rpm and tool transverse speeds of 50 and 100 MoreIn present research, the effect of tool transverse speed on the microstructure and mechanical properties of friction stir welded DP700 dual-phase steel has been studied. Welding process conducted at a rotational speed of 800 rpm and tool transverse speeds of 50 and 100 mm/min. Optical and scanning electron microscopy were used for microstructural examinations, and mechanical properties were evaluated using microhardness measurements and tensile test. Microstructural investigation revealed that the stir zone consists of bainite, acicular ferrite and polygonal ferrite. It was also revealed that the heat-affected zone (HAZ), based on the peak temperature (Tp), can be subdivided into three different regions: 1) inner HAZ, where Tp is higher than Ac3, 2) Middle HAZ, where Tp lies between Ac1 and Ac3, 3) Outer HAZ in which Tp is lower than Ac1. It was also found that the martensite phase tempers in OHAZ and the degree of tempering decreases with the increment of tool transverse speed. This results confirmed by microhardness measurements where the hardness reduction of the softened zone decreased from 28 to 20HV with an increment of tool transverse speed. The highest hardness of the joints corresponded to the stir zone, and its value increased from 345 to 375HV with rising tool transverse speed. Tensile test results showed that the ultimate strength of the joints was lower than the base metal (723MPa) and it increases from 662 to 671MPa with rising tool transverse speed. It was also revealed that increasing transverse speed improves the total elongation by 2.6%. Manuscript profile -
Open Access Article
64 - Effect of bonding time on microstructure and completion of isotherm solidification during TLP bonding of dissimilar nickel base superalloys IN738LC and Nimonic 75
Meysam Khakian Ghomi Mohammad Saeid Shahriari Saeid NateghJoining of Inconel 738 and Nimonic 75 nickel base superalloys using Ni-Cr-B-containing interlayer, MBF-80, performed by transient liquid phase process (TLP) at 1080, 1120, 1150 and 1180°C and different times. Bonding microstructure was studied using a scanning elect MoreJoining of Inconel 738 and Nimonic 75 nickel base superalloys using Ni-Cr-B-containing interlayer, MBF-80, performed by transient liquid phase process (TLP) at 1080, 1120, 1150 and 1180°C and different times. Bonding microstructure was studied using a scanning electron microscope (SEM) and a light microscope. Microstructural studies showed that in short bonding time, the microstructure consists of continuous eutectic intermetallic phases in the center line of the joint and with increasing bonding time at constant temperature, eutectic intermetallic phases gradually decrease from the bonding and finally completely disappear. In order to predict the time required to isotherm solidification completion, Fick’s diffusion equations were used and it was observed that there is a good agreement between the predicted time of isotherm solidification completion and experimental results. Manuscript profile -
Open Access Article
65 - Synthesis of (CZTS) Cu2ZnSnS4 Nanoparticles by Hydrothermal Method for Solar Cell Application
Mahnaz karbassi Saeid Baghshahi Nastaran Riahi Noori Roozbeh Siavash MoakharTraditional photovoltaic devices for replacing fossil fuels have problems, including high construction and installation costs. Hence, there is now more focus on the new generation of solar cells, including solar tiles with higher efficiency and lower const. Due to the e MoreTraditional photovoltaic devices for replacing fossil fuels have problems, including high construction and installation costs. Hence, there is now more focus on the new generation of solar cells, including solar tiles with higher efficiency and lower const. Due to the emergence of nanolayers and the extensive advances in the selection of raw materials and devices for the application of this type of layers, in the present study, the preparation and achievement of optimal conditions for the main layer of solar tile has been considered. The best sample containing adsorbent layer film ink was obtained from CZTS and was made by solothermal method at 550 ºC. Using X-ray diffraction (XRD) and Raman spectroscopy analysis, phase studies of the synthesized samples as well as the identification of functional groups in the compounds were performed. Field emission scanning electron microscopy (FESEM) was used to study the surface morphology and the microstructure of the prepared inks. A UV-Vis spectrophotometer was used to analyze the ultraviolet-visible absorption spectrum. XRD analysis showed the formation of pure cassiterite as well as the presence of secondary phases of CZTS in some samples. and the results were confirmed by Raman spectroscopy. In the studies, the sample synthesized at 550 ºC with crystalline structure of cassiterite with suitable peak intensities was selected as the most suitable sample. FESEM microscopy showed that all samples of CZTS nanoparticles had a petal-like shape and with increasing temperature the petals bended. Finally the best conditions for the homogeneity of the morphological particles of the sample were observed at 550 ºC. Also, based on the results of the EDS, the sample with the highest weight percentage of copper and the lowest weight percentage of sulfur had priority in terms of application in solar cell structures, such characteristics were observed in the sample synthesized at 550 ºC. UV-Vis results showed that the optical cleavage band of CZTS nanoparticles in the best sample was 1.49 eV. In general, the results of the studies in this work showed the appropriateness of the solothermal synthesis method and also the effect of temperature on the final characteristics of the thin film, including the type of structure, morphology, transmition and energy bandgap. Manuscript profile -
Open Access Article
66 - Investigating the Effect of Tungsten Element on the Microstructure and Mechanical Properties of Fe-C-Ni Hard Coating
Adel Mosadeghian hamid nazemy Mohammadreza Khanzadeh Gharahshiran Mansor SadeghiNasbIn this paper, the effect of tungsten element on microstructure and mechanical properties of Fe-C-Ni hard coating was investigated. Two hard coating electrodes were made with 10 and 30 gr of tungsten powder. The microstructure of the welding metals included fine carbide MoreIn this paper, the effect of tungsten element on microstructure and mechanical properties of Fe-C-Ni hard coating was investigated. Two hard coating electrodes were made with 10 and 30 gr of tungsten powder. The microstructure of the welding metals included fine carbides in the area of needle martensite and residual austenite. Electron microscopy studies showed that there were very fine cracks in the weld metal martensitic phase with 10 gr of tungsten but these microscopic cracks were not found in weld metal with 30 gr of tungsten. The results of the EDS analysis showed that the amount of soluble tungsten element in the austenite phase of both welding metals is high. This amount in weld metal with 30 gr of tungsten was about 3.66% higher than the weld metal with 10 gr of tungsten. The results of the XRD analysis showed that the phases present in the weld metal with 10 gr of tungsten included martensite, austenite and W2C carbide, but in the weld metal with 30 gr of tungsten in addition to these phases also iron oxides were observed. The results of hardness test showed that the average hardness of weld metal with 10 gr of tungsten is 42.5 RC and the average hardness of welding metal with 30 gr of tungsten is 49.6 RC. Manuscript profile -
Open Access Article
67 - Comparison of Isothermal Oxidation and Thermal Shock Properties of CoNiCrAlY Coating Sprayed by Atmospheric Plasma Spray and Nitrogen Gas Shrouded Plasma Spray Methods
Behzad Ghasemi Zia Valefi Saeid Taghi-ramezaniIn this research, the properties of the coating applied by conventional plasma spray and with inert gas shroud has been studied and compared, in the way that nozzle like part attached to plasma gun in order to protect the plasma jet by exiting nitrogen from the nozzle. MoreIn this research, the properties of the coating applied by conventional plasma spray and with inert gas shroud has been studied and compared, in the way that nozzle like part attached to plasma gun in order to protect the plasma jet by exiting nitrogen from the nozzle. The Microstructural characterization of the coatings was performed by optical microscope and scanning electron microscope equipped with energy dispersive spectroscope. Hardness of coatings is also measured by Vickers method under the applied load of 30 gram-force. Isothermal oxidation and thermal shock tests are done at 1000 and 950ºC respectively. Post-spray results show that the use of nitrogen gas shroud is useful and coating achieved by nitrogen shroud has less oxide and porosity and has more homogeneous structure. Results from isothermal oxidation show that TGO layer growth rate in the specimen sprayed by nitrogen shroud is less. Thermal shock test shows that the specimen sprayed by nitrogen shroud has more resistance against thermal shock due to layer by layer and regular growth of TGO and having less oxide and porosity in comparison with the same specimen sprayed without nitrogen shroud. Also, the microhardness of sprayed coating without nitrogen shroud was 35 Vikers more than the applied coating with nitrogen shroud. Manuscript profile -
Open Access Article
68 - Investigation of the Effects of HVOF Process Parameters on the Quality and Wear Properties of the Coating Tungsten Carbide on 4130 Steel
Javad Ansari Amirhossein Moghanian Morteza Saghafi YazdiPrevious studies have shown that thermal spraying methods on steels have extensive applications in various industries to increase high-quality wear-resistance coatings. One of these coatings, which is important in diverse industries and has been studied, is tungsten car MorePrevious studies have shown that thermal spraying methods on steels have extensive applications in various industries to increase high-quality wear-resistance coatings. One of these coatings, which is important in diverse industries and has been studied, is tungsten carbide. One of the methods of coating is the high-velocity oxygen fuel (HVOF) process. Scanning electron microscopy (SEM) was used to examine the microstructure of the coatings and also by examining SEM images from the lateral surface of the coated sample, the thickness and quality of the coating were examined. Additionally, X-ray diffraction (XRD) was used to determine the formed phases before and after the coating process and the results of the presence of WC and W6C2.54 carbides were confirmed.The wear test results showed that coated samples demonstrated higher wear resistance than the sample without coating (control). Meanwhile, the sample with spraying pressure of 7.2 Bar and a feeding powder rate of 72 g/min (W2) exhibited the best wear resistance among other coatings due to the more uniform distribution of tungsten carbide (WC) and less porosity. As a result, it was obtained that the spraying pressure in the process of HVOF process was more effective than the feeding rate of coating powders and a sample with the spray pressure of 7.2 Bar and powders feeding rate of 72 g/min (W2) was introduced as the optimal sample among all coatings with the highest abrasion wear resistance. Manuscript profile -
Open Access Article
69 - TLP Bonding of Al-Al3V Nano Composite and Evaluation of its Properties
Seyedeh Zahra Anvari Mahdi Rajabi Safora OshaghiIn this research, the bonding of aluminum matrix nanocomposites reinforced by Al3V particles was investigated using a transient liquid phase of bonding process and evaluating its properties. The effect of temperature and time of bonding on the properties was also invest MoreIn this research, the bonding of aluminum matrix nanocomposites reinforced by Al3V particles was investigated using a transient liquid phase of bonding process and evaluating its properties. The effect of temperature and time of bonding on the properties was also investigated. For this purpose, Al-Al3V nanocomposite components were first prepared for bonding. The copper metal was used as the intermediate layer and bonding of these components was investigated by the transient liquid phase method at 560, 580 and 600°C, and 20, 40 and 60 min. Scanning electron microscopy was used to evaluate the microstructure of the joint. The shear strength of the joints was also evaluated by a pressure test device. The results indicated better bonding at 580 and 600°C than other samples. With increasing bonding temperature, the melt volume increased at the bonding joint and thus a wider surface area is filled by melt. According to the microhardness results, the maximum hardness of the joint is at 600 ° C for 20 min due to the diffusion of copper and formation of Al2Cu precipitated particles around the joint seam. The maximum joint shear strength of 65 MPa was achieved at 600 ° C for 40 min. Manuscript profile -
Open Access Article
70 - Optimization of mechanical and dielectric properties by controlling densification and microstructure in silicon nitride ceramics prepared by hot pressing method
S. Salman S. Afghahi Amirhossein kouchaki foroshani Pouria Dehghani farhood heydariSilicon nitride ceramics are materials with excellent mechanical, dielectric and thermal properties which with such properties is one of the main candidates for use in high temperature environments. In this study, the effect of sintering temperature on microstructure co MoreSilicon nitride ceramics are materials with excellent mechanical, dielectric and thermal properties which with such properties is one of the main candidates for use in high temperature environments. In this study, the effect of sintering temperature on microstructure control and densification and optimization of mechanical and dielectric properties of silicon nitride ceramics prepared by hot pressing at different temperatures of 1500 °C, 1600 °C, 1700 °C and 1800 °C has been investigated. Scanning electron microscopy and X-ray diffraction have been used to study the microstructure and analysis of the formed phases, respectively. According to the X-ray diffraction pattern and the Gazara-Mesier relationship, in the sintered samples at 1600 °C and 1700 °C, all alpha phases were converted to beta, and in the sintered samples at 1500 °C, the conversion rate was 95.45%. Is. The results show that increasing the sintering temperature from 1500˚C to 1800˚C leads to larger rod-shaped grains and achieves dual microstructure and the average grain diameter has increased from 0.7 µm to 1.34 µm. sintered specimen at 1500 °C, with the lowest average diameter (0.7 µm) among other specimens, has the highest flexural strength of 550 ± 9.5 Mpa. Is By increasing the average grain size and decreasing the α/β phase ratio due to the increase in fusion temperature, the mean dielectric constant and tangent of the sample loss increased from 4.5 to 9.2 and from 0.099 to 0.22, respectively Manuscript profile -
Open Access Article
71 - Study of the effect of magnetic field on the surface roughness of the workpiece in electric discharge machining of Al2O3-reinforced A413 composite
Ahmadreza Mizbani Sayed Ehsan Mirmohammadsadeghi Ali MokhtarianIn this research, the effect of electric discharge machining input parameters on the surface roughness of A413 composite reinforced with 2.5% Al2O3, in two cases with the presence of a magnetic field and without a magnetic field was investigated and compared. The resear MoreIn this research, the effect of electric discharge machining input parameters on the surface roughness of A413 composite reinforced with 2.5% Al2O3, in two cases with the presence of a magnetic field and without a magnetic field was investigated and compared. The research presented with Taguchi experiment design approach which is based on L9 orthogonal array and iterative surface technique. The input parameters of these experiments include voltage (two levels), current intensity (three levels), pulse on-time (three levels) and pulse off-time (three levels). Experiments results show machined surface roughness reduction in presence of magnetic field up to 32 percent. The analysis of the results included the determination of signal-to-noise ratio diagrams corresponding to each of the input parameters and analysis of variance by Minitab software. The results show that the surface quality of the workpiece improves in the presence of a magnetic field compared to machining conditions without a magnetic field. Also, based on the results of analysis of variance in both cases, the current intensity is the most effective input parameter on the surface roughness of the workpiece made of A413 composite reinforced with 2.5% Al2O3. Manuscript profile -
Open Access Article
72 - Effect of heat treatment on mechanical properties, solidification structure and segregation of Inconel 625 alloy in additive manufacturing process by DLMD method
mohammad gavahian jahromi Reza Shoja Razavi hamed Naderi fareed kermaniDirect metal laser deposition is using for rebuilding and manufacturing parts. In this method, it is imperative to check the melting and solidification conditions. In this research the effect of the primary process parameters on the microstructure has been investigated. MoreDirect metal laser deposition is using for rebuilding and manufacturing parts. In this method, it is imperative to check the melting and solidification conditions. In this research the effect of the primary process parameters on the microstructure has been investigated. Distance of the dendritic arms, and the segregation of alloy elements, to determine the mechanical properties of IN625. According to the examination of the scanning electron microscope image, by moving from the interface to the top of the cladding. The solidification structure changed from columnar dendritic to coaxial dendritic with decreased G/R ratio. From the interface to the sample’s surface, the cooling rate increased, and the spread between the dendritic arms decreased. By moving away from the interface, the distance of the dendritic arm increases. By changing the laser power from 250 to 450 watts, the G/R ratio decreased from 1252.08 ℃/〖mm〗^2 to 970.34℃/〖mm〗^2 . It was conducting heat treatment led to the uniformity of alloy elements in the background phase. Also, with heat treatment, tensile strength, and elongation increased and yield strength decreased. Manuscript profile -
Open Access Article
73 - Optimization of Effective Parameters in the Stir Friction Extrusion Process on Porosity and Tensile Strength of SiC Ceramic Particles Reinforced AA1050 Aluminum Matrix Composite
Mojtaba Soleimanipour Reza Abedinzadeh Seyyed Ali Eftekhari Ali HeidariThis research, involved dynamic optimization of process parameters on the porosity and tensile strength of AA1050/SiC aluminum composite wires produced by friction stir extrusion (FSE) was carried out. In this regard, SiC ceramic particles reinforced AA1050 composite sa MoreThis research, involved dynamic optimization of process parameters on the porosity and tensile strength of AA1050/SiC aluminum composite wires produced by friction stir extrusion (FSE) was carried out. In this regard, SiC ceramic particles reinforced AA1050 composite samples were produced using the FSE process. Also, response surface methodology (RSM) was used to design of experiment. The rotational speed of the punch, extrusion force, and reinforcement percentage weight were determined as input variables of the process. The porosity and tensile strength of produced composite samples were determined as response variables. Analysis of variance (ANOVA) and regression analysis were used to analyze the obtained data. The results showed that rotational speed, extrusion force with second-order effects, and reinforcement percentage with linear effects were effective on the tensile strength and porosity of composite samples. Also, the optimization of FSE process parameters to reach the minimum percentage of porosity and maximum tensile strength was performed using the desirability method. Finally, the optimization results were evaluated based on the validation test. Also, by achieving the maximum value of the desirability function (0.9852), the optimal conditions of process input variables were a rotational speed of 787 rpm, an extrusion force of 11.7 kN, and a reinforcement percentage of 3.86% to simultaneously achieve the maximum ultimate tensile strength (155.4 MPa) and minimum porosity percentage (0.45%). Also, the values obtained from the optimization were compared with the experimental values and the accuracy of the results in tensile strength and porosity were confirmed with 2.57% and 6.78% errors, respectively. Manuscript profile -
Open Access Article
74 - Investigation of hardness and tribological behavior of Al/Al2O3-TiB2 surface nano-camposite It is made by friction machining
kamran Amini Moamad Masaeli