• List of Articles اصطکاک

      • Open Access Article

        1 - Estimating Price Delays on Tehran Stock Exchange
        Ali Ebrahim Nejad Mahdi Pedram Rad
        In an efficient market, prices should reflect all information available to investors. In reality, several frictions can prevent prices from incorporating the information immediately after disclosure. This can cause delays in the incorporation of information into prices More
        In an efficient market, prices should reflect all information available to investors. In reality, several frictions can prevent prices from incorporating the information immediately after disclosure. This can cause delays in the incorporation of information into prices and increase the premium investors require for investing in stocks. Using an empirical measure of price delays, we examine the effect of these frictions and the resulting price delays on the cross-section of expected returns on Tehran Stock Exchange. The delay measure is defined as a function of contemporaneous and lagged systematic information that is impounded into prices. If frictions prevent information from impacting prices contemporaneously, lagged information should have explanatory power for stock returns. We find that stocks with higher price delays tend to have a premium that is not explained by known risk factors of market risk, size, value, momentum and liquidity. Our results are robust to a number of empirical specifications, namely the zero-investment portfolio returns and Fama-Macbeth regressions Manuscript profile
      • Open Access Article

        2 - Identifying Banking Crisis Using Banking Stress Index in Iranian Economy (Dynamic Factor Model)
        samineh ghasemifar Abolfazl Shahabadi shamsollah shirinbakhsh mirhosien mousavi azam ahmadian
        By the fact that most of the public and private sector financing comes from the country's banking sector, It is important to maintain stability and prevent a crisis in the banking system. The purpose of this study is to identify the banking crisis using the Banking Stre More
        By the fact that most of the public and private sector financing comes from the country's banking sector, It is important to maintain stability and prevent a crisis in the banking system. The purpose of this study is to identify the banking crisis using the Banking Stress Index in the Iranian economy for the period of 1398-1388. The Banking Stress Index is the best benchmark for assessing the banking crisis that reflects uncertainty, instability and financial friction in the banking system. In this study, the design of a bank stress index was performed using a dynamic factor model. This model is estimated by the maximum likelihood method and the stochastic pattern of missing data. Using six variables determining the banking crisis in the country, two banking stress indices with two different natures have been estimated in time series to examine the stability of the banking system. Finally, both indices of stress showed estimation; there is a precise timing of the coincidence between the greatest amounts of bank stress and the shocks to the Iranian economy. It was also concluded that bank stress indicators reflect the effects of external factors, including sanctions on the banking system fundamental weaknesses of the banking system, as well as being able to predict banking crises Manuscript profile
      • Open Access Article

        3 - The role of monetary variables and financial frictions on the stock market in the form of DSGE model
        Lleila Barati yazdan goodarzi
        10.30495/jfksa.2022.21085
        The purpose of this paper is to investigate the impact of monetary policy and financial frictions on the stock market. In this study, the role of imperfections in financial markets as well as monetary policy on capital market performance and other macroeconomic variable More
        The purpose of this paper is to investigate the impact of monetary policy and financial frictions on the stock market. In this study, the role of imperfections in financial markets as well as monetary policy on capital market performance and other macroeconomic variables has been evaluated. In this regard, the statistical information of the period of 1989-2021 was used based on the frequency of seasonal data. The method used in this study is to solve the Dynamic Stochastic General Equilibrium (DSGE) model. The results obtained from the monetary policy shock in this study showed that due to the existence of imperfection in the financial markets, it leads to volatility and instability in the capital market. In fact, the shock of the monetary policy has led to a change in the rate of return in the markets and this issue has affected the demand and supply of stocks. In addition, the monetary policy shock has had real effects on the economy. Manuscript profile
      • Open Access Article

        4 - بررسی اثرات شوک‌های ناشی از اصطکاک مالی و توسعه مالی بر بخش‌های اقتصادی ایران
        ساره امیرمجاهدی علی رئیس پور رجبعلی سید عبدامجید جلائی رضا زینل‌زاده
        10.30495/jae.2023.71252.1467
        Manuscript profile
      • Open Access Article

        5 - Laboratory Study of The Effect of V-shaped Structure on Changes in Fishway Roughness
        maryam shahabi Javad Ahdiyan Marjan Narimousa Mehdi Ghomeshi Hossein Azizi Nadian
        10.30495/wsrcj.2022.64329.11268
        Background and Aim: In this study, a new overflow with a v-shaped structure was used as a barrier in the culvert. The main purpose of the present study was to investigate its performance on changes in flow resistance properties such as the square root of the Modi fricti More
        Background and Aim: In this study, a new overflow with a v-shaped structure was used as a barrier in the culvert. The main purpose of the present study was to investigate its performance on changes in flow resistance properties such as the square root of the Modi friction coefficient and the Manning roughness coefficient.Method:The present study experiments were performed on the physical model available in the hydraulic laboratory of the Faculty of Water and Environmental Engineering, Shahid Chamran University of Ahvaz. This physical model includes a laboratory flume 10 meters long, 0.25 meters wide, and 0.5 meters high. At the beginning of each experiment, the structures were glued to the flume bed at specified relative distances. After 24 hours of gluing the systems, the flume's flow rate and slope were adjusted. The desired flow rate was adjusted using a triangular overflow with an angle of 53 degrees located downstream of the flume and the slope through the jack. A point gauge with an accuracy of 0.1 mm was used to remove the water surface profile.Results: By increasing the dimensionless flow in a relative distance between structures and a certain slope, the manning roughness coefficient of the structure decreases. So that at a slope of 10%, the relative distance between the structures was 1.3, the value of the Manning roughness coefficient of the system from dimensionless flow decreased from 0.20 to 0.43 by 30%. By increasing the relative distance between structures at a certain flow rate, the manning roughness coefficient of the structure decreases, which is similar to the effect of the relative distance between structures on the square root of the friction drop coefficient of the structure.Conclusion: In examining the impact trend of the V-fish structure, it was found that dimensionless flow has an inverse effect on the flow friction coefficient and the manning roughness coefficient of the structure. On the other hand, the inverse relationship between landing number and flow friction coefficient, and manning coefficient of the structure was determined. It was found that the relative distance between the structures also has an inverse effect on the flow friction coefficient and the manning coefficient of the structure. The inverse effect of the Reynolds number on current resistance parameters was also extracted. The best condition of the fish road structure with v-shaped overflow occurs in the relative distance between the 1.3 and 10% slope structures. Manuscript profile
      • Open Access Article

        6 - Determination of Some Physical Properties of Pistachio Nut and Its Kernel (Qazvini Varieties)
        mohammad gholami porshokohi milad mohammadi shamami shahram mohseni ali mashallah kermani ehsan abdolalizadeh
        Introduction: Understanding the physical and mechanical characteristics and knowledge of agricultural products are important and vital and knowledge steps for post harvesting storage and preservation. In this study, several physical properties of the Qazvinian cultivars More
        Introduction: Understanding the physical and mechanical characteristics and knowledge of agricultural products are important and vital and knowledge steps for post harvesting storage and preservation. In this study, several physical properties of the Qazvinian cultivars (Qazvini and Boein zahra) of pistachio nut and their kernel and the effect of different levels of moisture content on their characteristics were evaluated.Materials and Methods: Physical properties that consisted of dimensional specifications such as three major diameter (length, width, thickness), unit mass, sphericity, geometric and arithmetic mean diameter, surface area, true volume, true density, bulk density, porosity and the static coefficient of friction at five levels of moisture content (3.5%, 12%, 19.5%, 27%,35.5% ) were measured.Results: The results of this investigation concerned with geometrical properties indicated that moisture had significant effects on the dimension, geometric and arithmetic mean diameter,sphericity, surface area of pistachio nut and its kernel in both cultivars.Conclusion: By increasing the moisture content, all the listed properties of both cultivars (Qazvini and Boein Zahra) have been increased. The highest static coefficient of friction for Qazvini and Boein Zahra cultivars is on aluminum and the lowest is on plastic surfaces. The kernels of Qazvini and Boein Zahra pistachio, had the highest coefficient on wood and the lowest coefficient on plastic and glass surfaces respectively. Manuscript profile
      • Open Access Article

        7 - Determination and Investigation of Some Physical and Mechanical Properties of Almond (Rabi Variety)
        M. Salimi M. Gholami Sh. Mohseni E. Abdolalizade
        Introduction: Optimum machinery and equipment designing for transportation, harvest andprocessing of agricultural products need the knowledge of physical and mechanical propertiesof the products.Materials and Methods: In this research, the physical properties consisting More
        Introduction: Optimum machinery and equipment designing for transportation, harvest andprocessing of agricultural products need the knowledge of physical and mechanical propertiesof the products.Materials and Methods: In this research, the physical properties consisting of dimensions,mass, average geometrical diameter, sphericity, surface area, volume and the process ofmoisture attraction and the mechanical properties including force, deformation, ruptureenergy and power of almond the variety of Rabi were determined and evaluated.Results: The average of geometrical diameter for the whole almond was 22.37 mm and for itskernel was 13.42 mm. The sphericity for the almond and its kernel were 0.654% and 0.523%respectively. By placing some samples of almond kernel in the water, the process of moistureabsorption of almond kernel was studied and the mathematical models were presented. Themoisture absorption of the kernel when placed in the water for a period of 9-13 hours was 36-41% and this raised to 44% after 18 hours.Conclusion: Statistical coefficient of friction of almond and its kernel on glass andgalvanized iron was the minimum, respectively. Study of the effect of moisture on thestatistical coefficient of friction showed that by increasing the moisture, this coefficientincreased. Investigation concerned with mechanical properties showed that the effect ofloading speed and direction on rupture force, energy and power in probability level of 1%were significant. Power consumption to rupture almond was increased by increasing the speedfrom 50 to 200 mm/min. By increasing loading speed the rupture force was significantlydecreased and deformation in rupture point was increased. Rupture force of almond in loadingin the direction of axis was minimum. Manuscript profile
      • Open Access Article

        8 - Evaluation of the effect of financial policies on Capital Market investment in financial friction
        Masood Aghaei Ali Najafi Moghadam SHADI Shahverdiani Roya Darabi
        This study evaluates the effect of financial policies on stock market investment in financial friction conditions. For this purpose, two models were designed based on financial policies (taxes and government expenditures) and in the period from 1991 to 2017, the short-t More
        This study evaluates the effect of financial policies on stock market investment in financial friction conditions. For this purpose, two models were designed based on financial policies (taxes and government expenditures) and in the period from 1991 to 2017, the short-term dynamic relationship, long-term state and error correction of the models were estimated with the Auto Regressive Distributed Lag (ARDL). The financial friction index is used in this study based on the definition of the interest rate gap (the difference between on the lending interest rate and the deposit interest rate). The results show that in terms of financial friction, fiscal policy had a significant and negative impact on the first model (tax based) and in the second model (based on government spending) a positive and significant effect on the total stock price index. This result is in line with Keynesian view. The financial friction index also had a negative effect on the total stock price index in both models. However, since taxation directly affects corporate liquidity, therefore, in fiscal policy based on tax revenues, the effect of fiscal friction on the dependent variable was more dependent on government spending than fiscal policy. The results of estimating the other variables in the models were that GDP based on Keynesian theory, oil revenues based on support theory and exchange rate in flow-oriented models had a significant and positive effect on the total stock price index. Manuscript profile
      • Open Access Article

        9 - Idiosyncratic Risk and Market Friction in Investment Process
        Mehdi Gholipur Khanegah Reza Eyvazloo Saeed Mahmoodzade Mehdi Rameshg
        Merton (1987) believes that under market friction, where investors pose limitations in access to information, stocks with high idiosyncratic volatility have higher expected return, because investors are not able to decrease company specific risk through diversification. More
        Merton (1987) believes that under market friction, where investors pose limitations in access to information, stocks with high idiosyncratic volatility have higher expected return, because investors are not able to decrease company specific risk through diversification. As in classical point of view, it is assumed that investors are just subject to systematic risk and only mentioned risk will be priced. Based on that view, unsystematic risk completely managed via diversification, while because of information cost and transaction cost in real world, investors hold limited number of stocks in their portfolios. This paper is going to study idiosyncratic risk and return in Tehran Stock Exchange using monotonic relationship. Our findings don’t approve monotonic relationship between expected return of idiosyncratic risk. Furthermore our results show that average return of high idiosyncratic portfolios is greater than low idiosyncratic portfolios. Manuscript profile
      • Open Access Article

        10 - Effect of Strengthening Particles on Microstructure and Tribological Properties of Aluminum Based Nano-composites
        A. Rabiezadeh A. Afsari
        Manuscript profile
      • Open Access Article

        11 - Experimental Investigation of the MoS2 Nanoparticles Effects on the Engine Oils Lubrication Characteristics and Frictio Coefficient
        S. Shokri Y. Mollaei-Barzi
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      • Open Access Article

        12 - Effect of Interpass Annealing Heat Treatment on Microstructural Evolutions, Mechanical and Wear Properties of in-situ Formed Al3003-Ti/Al3Ti Nanocomposite Fabricated via Friction Stir Processing
        M. Zadali Mohammad-Kotiyani K. Ranjbar
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      • Open Access Article

        13 - Microstructural Evaluation and Tribological Properties of Cu/ZrO2 Nano-Composite Produced by Friction Stir Processing
        S. Ghafaei A. Rabiezadeh
        Manuscript profile
      • Open Access Article

        14 - The effect of volume fraction and size of Al2O3 nanoparticle on heat transfer and flow characteristics in the heat exchanger with louvered strip inserts
        Meysam Pouyanian Ashkan Ghafouri
        In this study, the effect of using louvered strip inserts in heat exchangers on flow and transfer characteristics is numerically investigated. The continuity, momentum, and energy equations have been solved using a finite volume method. The wall of the tube is heated wi More
        In this study, the effect of using louvered strip inserts in heat exchangers on flow and transfer characteristics is numerically investigated. The continuity, momentum, and energy equations have been solved using a finite volume method. The wall of the tube is heated with a uniform heat flux boundary condition. This paper uses a louvered strip insert arrangement (forward) with a Reynolds number of 10,000. The effects of louvered strip slant angle of  and pitch of 50 mm were used for Al2O3 nanoparticles with different volume fractions in the range of 1% to 4% and different nanoparticle diameters in the range of 20 nm to 50 nm, mixed in a base fluid (water) is used. The comparison of numerical analysis results with existing equations has shown a good convergence. The numerical results reveal that the Nusselt number has increased with decreasing the nanoparticle diameter. The results indicate a slight change in the skin friction coefficient when nanoparticle diameters of Al2O3 nanofluid are varied. The Nusselt number increases with increasing nanoparticle volume fraction of Al2O3 /water nanofluid, while it is found that pure water has the lowest Nusselt number value. Also, the nanofluid has reduced the wall's temperature more than the base fluids (water), which indicates the advantage of using nanofluids in improving the system's thermal performance. Manuscript profile
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        15 - Experimental Study of Interfacial Friction Factor and Shear Stress in Counter-current Two-phase Flow in a Vertical Pipe
        Arash Ghafouri Ashkan Ghafouri Abbas kosarineia Alireza Daneh-Dezfuli
        In the experimental study, the formation of the annular flow pattern in a vertical pipe with the counter-current two-phase flow has been investigated with the help of image recording and processing techniques. After separating the created two-phase flow regime, the rang More
        In the experimental study, the formation of the annular flow pattern in a vertical pipe with the counter-current two-phase flow has been investigated with the help of image recording and processing techniques. After separating the created two-phase flow regime, the range of superficial velocity of air (upward) and water (downward) is 3.66-20.94 m/s and 0.06-0.31m/s for annular flow, respectively. The interfacial friction factor (liquid and gas phase) has been evaluated according to the hydrodynamic parameters of the flow. Comparing the average deviation of the results obtained from the current research with the previous research shows that the results are in good agreement. Also, the interfacial shear stress has been calculated and evaluated for two test pipes in the center-current two-phase flow pattern in the annular flow regime. In this research, the interfacial friction factor (liquid and gas phase) is also presented as a new correlation depending on the Reynolds number of the gas flow and the Reynolds number of the liquid flow with a coefficient of determination of R2=0.98. Manuscript profile
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        16 - بررسی تأثیر پارامترهای جوشکاری اصطکاکی اغتشاشی بر روی خواص مکانیکی و فیزیکی ناحیه جوش مواد کامپوزیتی با زمینه ی آلومینیمی
        بیژن محمدی لندی حسن کاوسی بلوتکی ایمان گل شکوه محمد گودرزی خویگانی
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        17 - Entropy generation in a sample gas distribution network using steel and polyethylene pipes
        Ali Heydari
        Natural gas is extracted from wells and after purification, it reaches to consumption stages by transmission and distribution network. Energy losses in this section is vital and must be calculated appropriately. In this study, the network of distribution with low workin More
        Natural gas is extracted from wells and after purification, it reaches to consumption stages by transmission and distribution network. Energy losses in this section is vital and must be calculated appropriately. In this study, the network of distribution with low working pressure is examined. A network sample of natural gas is investigated using analitical solution of a steady flow of natural gas. Flow equations initially provided for a tube considering all parameters. Then, using the existing rules in pipe networks the network sample is analyzed. Effect of tube material as an important factor on network performance are evaluated and analyzed And finally, the rate of entropy generation in steel and polyethylene pipes were compared. The results show that by increasing the diameter or decreasing the gas flow rate, the tube material and friction coefficient is less effective on entropy generation in practice. Furthermore, the gas flow in lower diameters cause more entropy production using steel pipes in compare with polyethylene pipes. Manuscript profile
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        18 - The effect of rounds of the Friction Stir Welding tool (FSW) in determining of fatigue life of T6-7075 aluminum alloy
        Mohamad Jafar Ostad Ahmad Ghorabi Reza Samieifard
        In this article, the use of Friction Stir Welding (FSW) process to create a proper connection of 7075 aluminum alloy parts and the effect of the number of revolutions of the welding tool on the fatigue life of the weld area have been investigated. After the process, usi More
        In this article, the use of Friction Stir Welding (FSW) process to create a proper connection of 7075 aluminum alloy parts and the effect of the number of revolutions of the welding tool on the fatigue life of the weld area have been investigated. After the process, using the optimization parameters, the fatigue life of the base metal and weld metal of the welded samples was obtained. The results show that performing the fusion-friction welding process by changing the number of revolutions of the welding tool on the fatigue life of the T6-7075 aluminum alloy welding zone has increased the fatigue life in the fusion zone, which is caused by the heat produced due to friction and the severe shape change of the material in It is during welding. Also, investigations showed that in the weld metal and its surroundings, a weaker area in terms of fatigue life than the base metal has been formed. Manuscript profile
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        19 - تولید کامپوزیت پایه فلزی Tio2/Al5083 به وسیله روش فراوری اصطکاکی اغتشاشی (FSP)
        رضا عبدی بهنق رسول سالک رستم محمد کاظم بشارتی گیوی
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        20 - Friction damper optimization based on parallel sensitivity analysis For self-centering concrete walls with gravity columns
        mohsen izadinia mahdi ravanbakhshian Hosein Tajmir Mohammadhasan Meisami
        In recent years, self-centering concrete walls have been used as modern structures. The mechanism of these structures is such that the focus of energy dissipation is on the dampers, and the role of the concrete wall and tendons is to create stiffness and provide the sel More
        In recent years, self-centering concrete walls have been used as modern structures. The mechanism of these structures is such that the focus of energy dissipation is on the dampers, and the role of the concrete wall and tendons is to create stiffness and provide the self-centering capacity in the system. in a way that reduces the residual deformation in the system. The most important point that should be considered in these structures is the optimal use of dampers in them. In this article, a new system has been introduced which is a combination of self-centering concrete walls with gravity columns. in such a way that the friction dampers were placed in the middle and side positions of the concrete wall. The main focus and goal of this research is to investigate the optimal numerical value for the "slip load of friction dampers" in the middle and side positions of the Self-centering concrete wall based on the "amount of prestressing force" in the friction screws of the dampers, as in the current study , the resistance of damper materials, their shape and dimensional size are not considered as variable parameters And in determining the optimal damping, they are considered without influence.In total, the optimal sliding load based on the tensioning force in the friction bolts has been simultaneously determined by two-way sensitivity analysis by OpenSEES software. Manuscript profile
      • Open Access Article

        21 - Friction damper optimization based on parallel sensitivity analysis for self-centering concrete walls with gravity columns
        mahdi ravanbakhshian mohsen izadinia Hosein Tajmir Mohammadhasan Meisami
        10.30495/civil.2023.705697
        In recent years, self-centering concrete walls have been utilized as modern structures. The mechanism of these structures is such that the focus of energy dissipation is on the dampers, and the role of the concrete wall and tendons is to create stiffness and provide the More
        In recent years, self-centering concrete walls have been utilized as modern structures. The mechanism of these structures is such that the focus of energy dissipation is on the dampers, and the role of the concrete wall and tendons is to create stiffness and provide the self-centering capacity in the system resulted in the reduction of residual deformation in the system. The jointed self-centering concrete walls are a type of self-centering wall system where dampers are placed between two concrete wall panels. The most important point that should be considered in these structures is the optimal use of dampers in them. In the present research, a new system has been introduced, which is a combination of self-centering concrete walls with gravity columns. In such a way that the friction dampers were placed in the middle and side positions of the concrete wall. This research aimed to investigate the optimal numerical value for the "slip load of friction dampers" in the middle and side positions of the Self-centering concrete wall based on the "amount of prestressing force" in the friction screws of the dampers. In the current study, the resistance of damper materials, their shape and dimensional size are not considered as variable parameters and they are considered without influence in determining the optimal damping. In total, the optimal sliding load based on the prestressing force in the friction bolts has been simultaneously determined by two-way sensitivity analysis by OpenSEES software. Based on the results, applying the method of determining the percentage of the minimum response coefficient (R) based on parallel (two-way) sensitivity analysis can be recognized as a very efficient method for determining the most optimal friction damper in Self-centering jointed concrete wall systems. Furthermore, the prestressed and optimal force for the dampers indicated that the dampers located between the two walls (set of middle dampers) exhibit a specific optimal value and other dampers (set of side dampers) also present a different optimal value. Manuscript profile
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        22 - Offering a New Computational Relationship to Evaluate the Bearing Capacity of the Strip Footing on the Two Frictional -Cohesive Layered Ground
        Loghman Rahimi navid ganjian Mikaiel Youssefzadehfard Mehdi Derakhshandi
        In this study, in order to provide a new analytical relationship for evaluating the bearing capacity of a two layered cohesive- frictional soil mass, 12 sets loading tests of physical model for three types of upper layers with different thicknesses and compactions. In c More
        In this study, in order to provide a new analytical relationship for evaluating the bearing capacity of a two layered cohesive- frictional soil mass, 12 sets loading tests of physical model for three types of upper layers with different thicknesses and compactions. In continuation, a series of parametric studies were performed to evaluate the accuracy of the proposed relationship using PLAXIS 2D finite element software. In order to study the results of numerical modeling and control of the accuracy of the modeling, results of these analyzes were compared with the experimental results of corresponding physical models by considering the effect of different parameters)relative thickness, compaction ratio and different shear strength parameters of  soil layers) on the failure mechanism and the ultimate bearing capacity of the soil. Considering the appropriate fit of the load-displacement curves, the failure pattern and the average difference of the bearing capacity about 3.3% between the physical and numerical models, show that finite element models have good accuracy in predicting the actual behavior of laboratory samples and the results of numerical simulations can be trusted. After the verifying of the numerical analysis results, the values of the bearing capacity obtained from both numerical and analytical methods for 88 different modes of the strip foundation with dimensions B = 1 and 2 meter and soil mass with different layering, depth and shear strength parameters were compared and a difference of about 7 and 12.5% were observed for foundations with dimensions of 1 and 2 meters, respectively. The results showed that there is a relatively good agreement between all three experimental, numerical and analytical methods in the evaluation of the ultimate bearing capacity and the analytical relationship can predict the process of limit pressure changes in terms of the relative thickness of the layers and the evaluation of the ultimate bearing capacity for various states of the strip footing resting on two layeres ground with relatively good accuracy. Manuscript profile
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        23 - Investigation of base shear in the steel structure with rotational friction damper influenced by the soil-structure interaction
        Alireza Lork SAEED ABACHI Ali Nikkhoo
        10.30495/civil.2022.697808
        Rotational friction dampers (RFDs) have been proposed as one of the passive control tools in order to increase the seismic performance and lateral control of structures and the loss of input energy of earthquakes through friction in their rotating plates.  Apply of More
        Rotational friction dampers (RFDs) have been proposed as one of the passive control tools in order to increase the seismic performance and lateral control of structures and the loss of input energy of earthquakes through friction in their rotating plates.  Apply of the rotational friction dampers will reduce shear stress and improve the dynamic response of the structures. In the nonlinear analysis and design of structures, the underlying soil is usually assumed to be rigid, if the flexibility effect of the structure bed is used, the dynamic characteristics of the structures will be different. Examining the behavior of structures by considering the effects of soil and structure interaction can give us a more accurate understanding of the behavior of structures, and this is while in most of the designed structures, the effects of soil stiffness and possible elevation of the foundation is not considered.  In this article, a typical ten-story building is considered and in it, with type two hard soil and type three soft soil, the performance of the damper with different damping capacity and interaction effect was analyzed with SAP 2000 software. Shear stress in different floors of the structure was analyzed in four cases: with dampers and with the effect of soil interaction and with dampers without the effect of soil interaction, without dampers with the effect of soil interaction, and without dampers and without the effect of soil interaction. The graphs showed how much the rotational friction damper can be useful in reducing the shear in different floors of the building, taking into account the effect of soil and structure interaction. Three earthquake records were utilized for this research and at the end, the results were compared with each other. The results indicated that the use of rotational friction dampers reduced the shear in all cases and the analysis of the sliding load of the damper and the required capacity of the structure were also obtained. Manuscript profile
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        24 - Investigation Effective Factors On Energy Depreciation Of Stepped Spillways
        saeed razmara Abbas mansori
        In recent decades, stepped spillways have been a significant role in this case.. This research is based on The flow energy calculated on these edged steps and simple steps in nappe flow and skimming flow regimes. Difference in height, width and edge slopes will determin More
        In recent decades, stepped spillways have been a significant role in this case.. This research is based on The flow energy calculated on these edged steps and simple steps in nappe flow and skimming flow regimes. Difference in height, width and edge slopes will determine the effects of each of these parameters on energy dissipation ratio And then the analysis of sixteen model with different geometries were conducted by Gambit and Fluent software for two discharges ٣/٦ lit/s (nappe flow) and ٢٥ litr/s (skimming flow) by the total of ٣٢ models. And with regard to the results achieved, the influence of the edge for nappe flow has been regarded according to Chamani and Rajaratnani equations. With regard to the results, it is suggested that the existence of the edge at the step end can be enhanced the energy dissipation ratio along the stepped chute. Of course the ratio of this effect in flow and skimming regimes are not the same and these effects are decreased by increasing of discharge. Manuscript profile
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        25 - بررسی افت و خیزهای اصطکاک در مقیاس نانو مبتنی برآمار وارون
        سکینه حسین آبادی بتول حسینی تلی لاله فرهنگ متین
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        26 - The effect of financial friction on the speed of stock price convergence
        Sepideh Rajizadeh Amirhossein Taebi Noghondari Hadis Zeinali
        Any factor that reduces the positive effects of rising stock prices creates a kind of financial friction for stocks. The role of financial friction in justifying the slowdown in stock price convergence is significant because it interferes with financial transactions and More
        Any factor that reduces the positive effects of rising stock prices creates a kind of financial friction for stocks. The role of financial friction in justifying the slowdown in stock price convergence is significant because it interferes with financial transactions and stock pricing, and investors are unable to completely reduce firm-specific risk through diversification if there is financial friction. The above issue is one of the new issues in the capital market that due to the novelty of the areas of financial friction and the speed of stock price convergence, little research has been done nationally and internationally; Less attention has been paid to this dimension of research variables. Therefore, the purpose of this study is to investigate the effect of financial friction on the speed of stock price convergence. The data of this study consisting of 89 companies listed on the Tehran Stock Exchange during the years 2010 to 2019 were reviewed. To test the research hypotheses, the generalized least squares regression model has been used. The results of the study indicate that there is a negative and significant relationship between financial friction and the speed of stock price convergence. Manuscript profile
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        27 - Effects of alumina nanoparticles, number of stirring pass and rotational speed on the mechanical behavior of friction stir welded (FSW) magnesium alloy (AM60)
        Arash Behzadineghad Abbas mohassel Hamid Omidvar Nader Setoudeh
        In this study, effects of alumina nanoparticles and stirring pass in mechanical behavior of friction stir welded AM60 magnesium alloy were studied. Microscopic analysis showed occurrence of dynamic recrystallization during plastic deformation in weld area and mechanical More
        In this study, effects of alumina nanoparticles and stirring pass in mechanical behavior of friction stir welded AM60 magnesium alloy were studied. Microscopic analysis showed occurrence of dynamic recrystallization during plastic deformation in weld area and mechanical tests revealed optimum condition for hardness and tensile strength could be produced in 1200 rpm rotational speed not only in absence of reinforcing alumina nanoparticles but also in presence of them. Opposing effects of higher temperatures in grain growth and greater strains in lowering grain size should be considered. In lacking of alumina nanoparticles, grain size diminished with increasing stirring pass but in being nanoparticles, predominant mechanism in depressing grain size came from nanoparticles and negligible effect of stirring pass in grain size was found. XRD results showed increasing solubility of γ-Mg phase as a result of stirring operation. Better toughness performance of weldment was produced via decreasing size of agglomerated alumina particles. Higher hardness and greater ultimate tensile strength were achieved in specimens with alumina nanoparticle with increasing rotational speed. In a constant rotational speed, higher hardness and greater ultimate tensile strength achieved in samples having alumina nanoparticles in contrast with free alumina nanoparticle samples Manuscript profile
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        28 - 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 نادری
        In 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 More
        In 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
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        29 - Comparison of Corrosion behavior of aluminium 6061 alloy joined by friction stir lap welding and gas tungsten arc lap welding methods
        reza bazarganlari ehsan vafa
        In this paper wrought aluminum sheets with thickness of 5 mm were square butt welded by friction stir lap welding (FSLW) and gas tungsten arc lap welding (GTALW) methods to campare their corrosion behavior. of the welding zone was probed by tafel polarization curve. Opt More
        In this paper wrought aluminum sheets with thickness of 5 mm were square butt welded by friction stir lap welding (FSLW) and gas tungsten arc lap welding (GTALW) methods to campare their corrosion behavior. of the welding zone was probed by tafel polarization curve. Optical metallography (OM) and scaninig electron microscop (SEM) were used to study morphology. Energy dispersive spectroscopy (EDS) were used to analysis different zone of the welds. EDS analysis proved deposits of iron and silicon in samples. FSLW and GTALW resulted in equiaxed grains of about 5 and 18 micrometr respectively, while GTALW caused dendritic structure of the welded region. To assessment mechanical properties, micro hardness test were accure. Resistance to corrosion was greater for the FSLW grains than the GTALW structure. In both cases, susceptibility to corrosion attack was greater in the welded region than the base metal section. . microhardness of FSLW specimen were grater than GTALW specimen. Manuscript profile
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        30 - Similar and dissimilar 5754 and 6063 aluminum alloy joints by friction stir welding
        امین ربیعی زاده احمد افسری فرهاد ارغوانی فرناز احمدی کیسمی
        The 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 More
        The 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
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        31 - Evaluation of Microstructure and Mechanical Properties of Friction Stir Lap Welded 6061 Aluminium Alloy at various welding speeds
        فرهاد غروی ایمان ابراهیم زاده علی سهیلی
        In 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 More
        In 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
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        32 - Fabrication of in situ Al-Ni surface composite on 2024 aluminum alloy by friction stir processing
        ابراهیم بهرامی مرتضی شمعانیان حسین ادریس
        In this research, in situ Al-Ni surface composite produced on 2024 aluminum alloy using friction stir processing (FSP). FSP performed at a tool rotating rate of 1250 rpm and travel speed of 24 mm/min with and without nickel powder. Metallographic images show that the gr More
        In this research, in situ Al-Ni surface composite produced on 2024 aluminum alloy using friction stir processing (FSP). FSP performed at a tool rotating rate of 1250 rpm and travel speed of 24 mm/min with and without nickel powder. Metallographic images show that the grain size after FSP has reached about 30% of primary metal grain size. With the addition of nickel powder, intermetallic compound of Al3Ni is formed in situ. Micro-Vickers test demonstrates that the reinforcement particles (Ni) have uniform distribution near the surface of primary metal. After FSP, primary metal hardness of about 54 vickers reached to in its maximum value of 120 vickers and 129 vickers in stir zone without and with addition of nickel powder, respectively. The results show that the fabrication of in situ composite using FSP has improved the wear resistance of the primary metal. Manuscript profile
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        33 - 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 زاده
        Friction 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 More
        Friction 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
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        34 - Study the microstructure and hardness of FSW of API 70 steel at the presence of TiO2 particles
        Rasoul Pouriamanesh KAMRAN Dehghani
        In this study, the microstructural properties and hardness of Friction Stir Welded (FSWed) of high strength low alloy API X70 steel at the presence of titanium dioxide (TiO2) particles were investigated. In this regard, a homogeneous mixture of TiO2 and X70 steel powder More
        In this study, the microstructural properties and hardness of Friction Stir Welded (FSWed) of high strength low alloy API X70 steel at the presence of titanium dioxide (TiO2) particles were investigated. In this regard, a homogeneous mixture of TiO2 and X70 steel powders were inserted into the weld groove before applying FSW. The FSW method was applied on HSLA X70 with and without addition of titanium oxide (TiO2) particles. The optical microscopy and Vickers microhardness measurements were employed to evaluate the microstructure and hardness of the different weldments zones. The results showed that the hardness of various zones in the weldment are strongly depended on the microstructure which is affected by heat input and stiring action. In addition, the TiO2 particles were homogenously dispersed in the stir zone of TiO2-doped weldment and subsequently has changed the microstructure and hardness. In particular, a transition from an acicular ferrite (AF) dominant microstructure with a hardness value of 300 HV to a polygonal ferrite (PF) dominant microstructure with a hardness value of 180 HV was observed by moving from top surface region to near root region. Manuscript profile
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        35 - Effect of Shoulder Surface Angle of Tool on Joint Properties in Friction Stir Welding of 5052 Aluminium Alloy
        فرهاد غروی
        Friction 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 More
        Friction 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
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        36 - Effect of Tool Rotation Speed on the Mechanical Properties and Corrosion Behavior of Dissimilar Friction Stir Welded of 5083 Aluminium Alloy and Commercially Pure Titanium
        Masoud Shabani بهروز شایق بروجنی رضا ابراهیمی کهریزسنگی
        In this paper, the effect of tool rotation speed on the mechanical properties and corrosion behavior on dissimilar joints Friction Stir Welds between 5083 Aluminium alloy and pure Titanium is investigated. At first, with primary welding parameters range necessary to ach More
        In this paper, the effect of tool rotation speed on the mechanical properties and corrosion behavior on dissimilar joints Friction Stir Welds between 5083 Aluminium alloy and pure Titanium is investigated. At first, with primary welding parameters range necessary to achieve suitable connection obtained and then by changing tool rotation speed, mechanical and corrosion properties of heat affected zones, welding zones and cross section zones, by using polarization Tafel test and Electrochemical Impedance Spectroscopy was investigated and the result were compared. the result indicates that corrosion behavior of connections, is impressionable of the tool rotation speed and welding zone and heat affected zones have weaker corrosion resistance compared to the base metals. Manuscript profile
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        37 - 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 Derazkola
        In 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 More
        In 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
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        38 - 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-Manesh
        The 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 More
        The 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
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        39 - 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 قاسمی
        In-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 More
        In-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
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        40 - 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 Taghian
        The 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 More
        The 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
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        41 - Modification of Microstructure and Enhancing Mechanical Properties of as-cast AZ91 Magnesium alloy via Friction Stir Processing
        Hassan Jiryaei Sharahi Majid Pouranvari Mojtaba Movahedi
        10.30495/apme.2021.681639
        Magnesium 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 More
        Magnesium 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
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        42 - 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 Ghanbari
        In 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 More
        In 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
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        43 - Effect of Rotational Speed on Microstructure and Mechanical Properties of AA5456 Alloy Welded by FSW-Lap Joint
        mohamad ali safarkhanian
        Friction 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 More
        Friction 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
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        44 - Evolution of the Microstructure and Mechanical Properties of Friction Stir Welded Ferrite-Martensite DP700 Dual Phase Steel
        Mahdi Mahmoudiniya Amir Hossein Kokabi Massoud goodarzi
        In 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 More
        In 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
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        45 - 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 Heidari
        This 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 More
        This 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
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        46 - Evaluation of wear properties of Al7075/SiC-BN hybrid nano-composite surface layer produced by friction stir processing
        Mahmoud Soleymani Seyed Farshid Kashani Bozorg AliMohamad Hadian
        Friction stir processing technique was carried out to produce a 7075Al/SiC-BN hybrid nano-composite surface layer on 7075 Al substrate in order to improve hardness and wear resistance. Equal weight ratios of micron-sized SiC and nano-sized BN powder were placed in a gro More
        Friction stir processing technique was carried out to produce a 7075Al/SiC-BN hybrid nano-composite surface layer on 7075 Al substrate in order to improve hardness and wear resistance. Equal weight ratios of micron-sized SiC and nano-sized BN powder were placed in a groove in the front side of the rotating and advancing tool. In order to achieve homogeneity, five additional passes were carried out. Microscopic investigations showed near uniform distribution of the particles in a matrix of ultra-fine Al grains of less than 1mm. The micro hardness and wear resistance of the friction stir processed substrate (without introduction of SiC and BN powder) and fabricated 7075Al/SiC-BN hybrid nano-composite layer were found to be markedly lower than those of the as–received 7075Al-T6 due to dissolution of 7075Al-precipitates during thermo-mechanical regime of the process. However, these were found to increase to about one third over those of the as-received 7075Al-T6 substrate after subsequent T6 heat treatment of the fabricated hybrid nano-composite layer. Such treatment was associated with the formation of intermetallic-based precipitates. Manuscript profile
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        47 - Evaluation of microstructure and mechanical properties of friction stir welding API-X56 steel
        Ali Reza Nazemorroaya Mahmoud Fazel-najafabadi
        Manuscript profile
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        48 - Effect of Friction Stir Welding (FSW) on Corrosion Behavior of Pure Copper in 3.5 % wt NaCl Solution
        amirhossein taheri Arash Fattah-alhosseini
        In the present study, the effect of friction stir welding (FSW) on the corrosion behavior of pure copper in 3.5 % wt NaCl solution was investigated. For this purpose, pure copper was welded using a rotation speed of 355 rpm and welding speed of 20, 28, and 40 mm/min. Th More
        In the present study, the effect of friction stir welding (FSW) on the corrosion behavior of pure copper in 3.5 % wt NaCl solution was investigated. For this purpose, pure copper was welded using a rotation speed of 355 rpm and welding speed of 20, 28, and 40 mm/min. The microstructures of the pure copper and welded pure copper were evaluated using X-ray diffraction (XRD) and scanning electron microscopy (SEM). Also, corrosion behavior of the specimens was investigated using Tafel polarization, and electrochemical impedance spectroscopy (EIS) in 3.5 % wt NaCl solution. Results revealed that FSW decreased the grain size of pure copper and improved the corrosion resistance of the stir zone. Manuscript profile
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        49 - بررسی اثر تغییرات زمان توقف ابزار در فرآیند جوشکاری اصطکاکی اغتشاشی نقطه‌ای(FSSW) بر ریزساختار آلیاژ Ti-6Al-4V
        سعید نادر مسعود کثیری مرتضی شمعانیان
        Manuscript profile
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        50 - بررسی شکل‌گیری عیوب و لایه‌های بین فلزی در جوشکاری اصطکاکی اغتشاشی آلومینیم AA1100 به فولاد A441 AISI
        حامد آقاجانی درازکلا مجید الیاسی مرتضی حسین زاده
        Manuscript profile
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        51 - بررسی نسبت سرعت دوران به پیشروی ابزار در جوشکاری هم‌زن اصطکاکی اتصال غیر هم‌جنس آلیاژ آلومینیوم 5083 به تیتانیوم خالص تجاری
        مجتبی صادقی گوغری مسعود کثیری کامران امینی
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        52 - بررسی عددی انتقال حرارت و جریان آرام نانوسیال آب-اکسید آلومینیم در ‏میکروکانال مستطیلی دندانه‌دار
        داود طغرایی آرش کریمی پور امید علی اکبری مجید زرین قلم حبیب اله عالی‌پور
        This paper numerically examines the laminar forced convection of a water–Al2O3 nanofluid flowing through a horizontal rib-microchannel. The middle section of the down wall microchannel is Affected by cold temperatures with a constant and uniform tempreture Tc. The m More
        This paper numerically examines the laminar forced convection of a water–Al2O3 nanofluid flowing through a horizontal rib-microchannel. The middle section of the down wall microchannel is Affected by cold temperatures with a constant and uniform tempreture Tc. The middle section is also influenced by a transverse rib array. The effects of height rib in a two dimensional rib-microchannel on flow and heat transfer parameters of laminar water-Al2O3 nanofluid are investigated. The characteristics of this research are numerically investigated by the commercial software Fluent 6.3 in a Reynolds number as Re=10 and Re=100. Four different states of hight rib are analyzed. Higher conventional internal ribs or increasing the turbulators can significantly improve the performances of the convective heat transfer within a microchannel. It is seen that larger height rib and volume fraction of nanoparticles corresponds more heat transfer rate; however the added high ribs can cause a larger friction factor than that in the corresponding microchannel by constant height rib. At present article the effect of height rib on the fluid flow parameters are also studied for all different states of it. The results show that the microchannel performs better heat transfers at higher values of the Reynolds numbers. For all values of the Reynolds numbers and volume fraction of nanoparticles considered in this study, the average Nusselt number on the middle section surface of the microchannel increases as the solid volume fraction increases. Manuscript profile
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        53 - بررسی اثر سرعت خطی و دورانی ابزار بر روی جریان مواد و تولید حرارت در جوشکاری اصطکاکی اغتشاشی پلی متیل متاکریلات (PMMA)
        حامد آقاجانی درازکلا
          در این پژوهش اثرات سرعت خطی و سرعت دورانی ابزار جوشکاری اصطکاکی اغتشاشی بر روی توزیع و تولید حرارت در سطح و درون اتصال، سیلان مواد و هندسه‌ی محل اغتشاش پلی متیل متاکریلات (PMMA)، مورد مطالعه قرار گرفت. به‌منظور شبیه‌سازی فرآیند از روش دینامیک سیالات محاسباتی از م More
          در این پژوهش اثرات سرعت خطی و سرعت دورانی ابزار جوشکاری اصطکاکی اغتشاشی بر روی توزیع و تولید حرارت در سطح و درون اتصال، سیلان مواد و هندسه‌ی محل اغتشاش پلی متیل متاکریلات (PMMA)، مورد مطالعه قرار گرفت. به‌منظور شبیه‌سازی فرآیند از روش دینامیک سیالات محاسباتی از مجموعه نرم افزار تجاری CFD Fluent 6.4 استفاده شد. برای بالا بردن دقت شبیه‌سازی، خط جوش که در مرز بین قطعه‌کارها قرار داشت، به عنوان یک سیال غیر نیوتنی با رفتار شبه‌مذاب در اطراف پین ابزار مدل سازی شد. نتایج حاصل از شبیه سازی نشان داد که با افزایش نسبت سرعت چرخشی به سرعت خطی ابزار، جریان مواد در جلو ابزار اندکی بیشتر می‌شود و ابعاد منطقه اغتشاش بزرگتر می‌گردد. بیشینه درجه حرارت تولید شده و اغتشاش مواد در سمت پیشرو اتصال مشاهده شد. نتایج حاصل از این مدل توسط نتایج تجربی مورد مقایسه قرار گرفت و تطابق قابل قبولی با آنها داشت. براساس پارامترهای جوشکاری مورد بررسی، حداکثر حرارت تولید شده 115 درجه سانتیگراد، بیشینه سرعت جابجایی مواد 24/0 متر بر ثانیه در شانه ابزار و بیشینه فشار ایجاد شده بر روی سیال 9 مگاپاسکال در محل اتصال پیش بینی شد. Manuscript profile
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        54 - بهینه سازی پارامترهای جوشکاری فولاد کم‌کربن EN 10130 به روش جوشکاری اصطکاکی-اغتشاشی
        اکبر علیمحمدی مسعود کثیری مسعود افرند حسین نوروزی فروشانی
        فرایند جوشکاری اصطکاکی-اغتشاشی یک روش نو و جدید جوشکاری حالت جامد است که در اثر اصطکاک بین پین و شولدر و قطعه کار، تولید حرارت می کند. این حرارت باعث ایجاد یک منطقه خمیری شکل می‌شود. نیروی فشار از طرف شولدر و چرخش پین و ادغام لبه های اتصال سبب انجام جوشکاری می‌شود. در ا More
        فرایند جوشکاری اصطکاکی-اغتشاشی یک روش نو و جدید جوشکاری حالت جامد است که در اثر اصطکاک بین پین و شولدر و قطعه کار، تولید حرارت می کند. این حرارت باعث ایجاد یک منطقه خمیری شکل می‌شود. نیروی فشار از طرف شولدر و چرخش پین و ادغام لبه های اتصال سبب انجام جوشکاری می‌شود. در این پژوهش ابتدا به بررسی جوش پذیری ورق‌ فولادی EN10130 با ضخامت 5/1 میلی‌متر پرداخته شد و پارامترهای سرعت دورانی، سرعت پیش روی ابزار، قطر پین و شولدر، توسط 58 عدد آزمایش مورد بررسی قرار گرفته است. پس از ایجاد جوش‌هایی بدون عیب، بازه 500 تا 1000 دور بردقیقه برای سرعت دورانی و بازه 30 تا 160 میلی‌متر بر دقیقه برای سرعت خطی بترتیب به عنوان سطوح بالا و پایین مناسبی برای این پارامترها انتخاب شده‌اند. برای دست‌یابی به بیشترین استحکام کششی، تعداد 29 آزمایش با توجه به سطوح معین شده پارامترها، از روش باکس بنکن طراحی شده، سپس متدولوژی سطح پاسخ برای بهینه‌سازی پارامترها مورد استفاده قرار گرفته است. نتایج بهینه‌سازی و شرایط آزمایشگاهی همخوانی خوبی داشتند که این نتیجه، نشان دهنده کفایت مدل طراحی آزمایش‌ها و نتایج پیش‌بینی بهینه‌سازی است. آزمایش‌های ریز سختی سنجی، متالوگرافی و تست کشش نرمال صورت گرفته روی 3 سری از ورق‌های تولید شده با مناسب‌ترین استحکام کششی و ازدیاد طول، منطقه متأثر از حرارت ورق ‌های سمت پیشرونده را ضعیف‌تر از بقیه موضع جوش معرفی کردند   Manuscript profile
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        55 - بررسی تأثیر ضریب اصطکاک بر میزان عیب دم ماهی در فرایند نورد حلقوی گرم
        امیر حسین قیصری محمدرضا فروزان عبدالعلی مراثی
        نورد حلقوی گرم یک فرایند به شدت غیر خطی و ناپایدار است. ضریب اصطکاک میان رینگ با غلتک محرک و هرزگرد از این جمله اند که بر کیفیت محصول نهایی تأثیر به‌سزایی دارند. در این مقاله تأثیر این دو پارامتر بر نورد حلقوی گرم به کمک مدل  سه بعدی المان محدود کوپل مکانیکی- حرارت More
        نورد حلقوی گرم یک فرایند به شدت غیر خطی و ناپایدار است. ضریب اصطکاک میان رینگ با غلتک محرک و هرزگرد از این جمله اند که بر کیفیت محصول نهایی تأثیر به‌سزایی دارند. در این مقاله تأثیر این دو پارامتر بر نورد حلقوی گرم به کمک مدل  سه بعدی المان محدود کوپل مکانیکی- حرارتی بررسی شده است. بدین منظور مدلی سه بعدی از فرایند نورد حلقوی گرم شامل رینگ، غلتک­های محرک، هرزگرد و راهنما در نرم افزار آباکوس ایجاد شده و میزان عیب دم ماهی به ازای ضریب اصطکاک­های مختلف میان غلتک محرک و حلقه و همچنین غلتک هرزگرد و حلقه اندازه‌گیری شده است. نتایج نشان می­دهد که با افزایش ضریب اصطکاک میان رینگ و غلتک هرزگرد یا کاهش ضریب اصطکاک میان رینگ و غلتک محرک میزان عیب دم ماهی کاهش می­یابد. همچنین میزان تغییرات این دو پارامتر باید در محدوده معینی حفظ شده و از آن تجاوز ننماید. نتایج به‌دست آمده می­تواند به عنوان راهنمایی به منظور بهینه سازی فرایند مزبور به کار گرفته شود. Manuscript profile
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        56 - استفاده از روش نشر اکوستیک برای مطالعه خرابی سطح در فرایند اصطکاک
        مهدی احمدی
        در این مقاله با استفاده از پایش سیگنال الکتریکی یک سامانه نشر اکوستیک، تغییر شرایط در سطح مالش مورد بررسی تجربی قرار گرفته است.  اصطکاک با لغزش یک حلقه فولادی بر سطح یک ورق فلزی شبیه سازی شده است. در اثر حرکت حلقه، آشوب‌ مکانیکی در سطح فلز ایجاد می‌شود که به صورت ا More
        در این مقاله با استفاده از پایش سیگنال الکتریکی یک سامانه نشر اکوستیک، تغییر شرایط در سطح مالش مورد بررسی تجربی قرار گرفته است.  اصطکاک با لغزش یک حلقه فولادی بر سطح یک ورق فلزی شبیه سازی شده است. در اثر حرکت حلقه، آشوب‌ مکانیکی در سطح فلز ایجاد می‌شود که به صورت امواج تنشی در سطح منتشر می‌شود. با استفاده از یک حسگر پیزوالکتریک، جابه‌جایی ناشی از گذر موج تنش به صورت سیگنال الکتریکی دریافت می‌شود که از آن برای تحلیل وضعیت اصطکاک استفاده می‌شود. نتایج به‌دست آمده نشان می دهد که میزان تأثیر عوامل مختلف مثل نیروی عمودی، جنس مواد و استفاده از روانکار بر خرابی سطح را می‌توان با تحلیل سیگنال الکتریکی مشاهده کرد. به‌عنوان مثال، مطالعه سیگنال حاصل از مالش دو سطح نشان می دهد که با مضمحل شدن لایه نازک روانکار بین دو سطح، سیگنال‌های مربوط به تشکیل خرابی‌های میکروسکپی با دامنه و فرکانس معین ظاهر می‌شوند. حساسیت روش مورد استفاده برای تشخیص خرابی نسبت به روش پایش اصطکاک به مراتب بیشتر بوده و از این روش می‌توان برای پایش وضعیت سطح در فرایند اصطکاکی استفاده کرد Manuscript profile
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        57 - بررسی آزمون اصطکاکی تی شکل برای آلیاژ تیتانیوم در دمای بالا
        فرزان براتی یاسر نعمتی
        متغیرهای متعددی بر فرایند شکل­دهی فلزات تاثیر گذار می­باشند که یکی از مهمترین آنها اصطکاک است.اصطکاک بر نحوه سیلان ماده و همچنین نیروی مورد نیاز برای شکل­دهی اثر گذار می باشد. برای تعیین میزان و نحوه تاثیر آن داشتن مقدار دقیق ضریب اصطکاک ضروری است. این مقاله More
        متغیرهای متعددی بر فرایند شکل­دهی فلزات تاثیر گذار می­باشند که یکی از مهمترین آنها اصطکاک است.اصطکاک بر نحوه سیلان ماده و همچنین نیروی مورد نیاز برای شکل­دهی اثر گذار می باشد. برای تعیین میزان و نحوه تاثیر آن داشتن مقدار دقیق ضریب اصطکاک ضروری است. این مقاله مربوط به مطالعه تجربی و عددی روی آلیاژ تیتانیوم با استفاده از آزمون اصطکاکی تی شکل در دمای بالا است. و با استفاده از شبیه سازی اجزا محدود و آزمایش‌های تجربی اثرات پارامترهای دما، سرعت ، شعاع گوشه قالب، و شرایط اصطکاکی در آزمون تی شکل مورد مطالعه قرار گرفته است. بر اساس نتایج تجربی و عددی مشخص شد حساسیت اصطکاک در آزمایشتی شکلبا افزایش سرعت قالب یا کاهش شعاع لبه قالب و دمای آزمون،افزایش می­یابد. همچنین همخوانی بین مقادیر ضریب اصطکاک به دست آمده به وسیله نرم افزار تحلیل اجزا محدود و منحنی کالیبراسیون اصطکاکی برای شرایط مختلف اصطکاک دیده شد. Manuscript profile
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        58 - بررسی اثر اصطکاک بر تعریض و برآمدگی جانبی در نورد تخت ‌ به روش المان محدود
        محمود سلیمی امین فضیله
        دراین مقاله با شبیه سازی سه بعدی نورد تخت در نرم افزارABAQUS، اثرات اصطکاک بر پخش عرضی و برآمدگی در سطوح مورد بررسی قرار گرفته است. برای تخمین این مقادیر، فرایند نورد به وسیله فورجینگ‌های پی در پی تخمین زده شده و افزایش طول یا تعریض متوسط از محاسبات قبلی مورد استفاده قر More
        دراین مقاله با شبیه سازی سه بعدی نورد تخت در نرم افزارABAQUS، اثرات اصطکاک بر پخش عرضی و برآمدگی در سطوح مورد بررسی قرار گرفته است. برای تخمین این مقادیر، فرایند نورد به وسیله فورجینگ‌های پی در پی تخمین زده شده و افزایش طول یا تعریض متوسط از محاسبات قبلی مورد استفاده قرار گرفته است. نتایج به‌دست آمده بصورت نمودارهایی ارائه شده که نشان می‌دهد با افزایش اصطکاک، تعریض و برآمدگی جانبی ورق در نورد تخت افزایش می‌یابد. نتایج ت‍ئوری مدل سازگاری خوبی را با مقادیر تجربی پ‍‍‍ژ‍وهشگران نشان می‌دهد. همچنین نتایج حاصل از اثر نسبت‌های مختلف عرض و ضخامت بر طول ناپایدار در نورد ورق مورد بررسی قرار گرفته است. Manuscript profile
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        59 - بهینه‌سازی ابعاد پلیسه، قطعه کار و فاکتور اصطکاک در فورجینگ سرد با قالب بسته
        مهدی ظهور حسین شاهوردی امین تفکری
        در این مقاله، در طراحی فرایند فورجینگ با قالبهای بسته غیر دقیق برای قطعات متقارن محوری، سه پارامتر نسبت عرض به ضخامت پلیسه، نسبت ارتفاع به قطر قطعه کار (بیلت) و فاکتور اصطکاک، با روش اجزا محدود مورد بررسی قرار گرفته است. همچنین دو عامل مهم در فرایند فورج شامل نیروی لازم More
        در این مقاله، در طراحی فرایند فورجینگ با قالبهای بسته غیر دقیق برای قطعات متقارن محوری، سه پارامتر نسبت عرض به ضخامت پلیسه، نسبت ارتفاع به قطر قطعه کار (بیلت) و فاکتور اصطکاک، با روش اجزا محدود مورد بررسی قرار گرفته است. همچنین دو عامل مهم در فرایند فورج شامل نیروی لازم برای فورج و مقدار پرشدن فضای داخلی قالب بررسی گردید. با کنترل ابعاد پلیسه، امکان کاهش مقدار دور ریز مواد مصرفی و افزایش درصد پرشدن قالب ایجاد می‌شود. برای اعتبار سنجی نتایج این کار تحقیقاتی، مقدار نیروی به‌دست آمده از روش اجزا محدود با مقدار نیروی کار تجربی مقایسه شده است. برای هماهنگ کردن و ارتباط دادن بین پارامترهای مذکور و به‌دست آوردن تابع عملکرد، شبکه عصبی دولایه بکار گرفته شده است. با به­کارگیری تابع به­دست آمده از شبکه عصبی و استفاده از الگوریتم ژنتیک، فاکتور اصطکاک و ابعاد پلیسه و قطعه‌کار برای کاهش مقدار نیرو و افزایش درصد پر شدن قالب به‌دست آمد. سپس، این مقادیر با نتایج کار تجربی مرجع دیگر، مقایسه شده است. الگوریتم ژنتیک تخمین قابل قبولی برای پارامترهای مؤثر در فرایند فورج ارائه کرد، به طوری‌که تطابق و نزدیکی خوبی بین نتایج این الگوریتم و روش تجربی وجود دارد. Manuscript profile

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