• فهرس المقالات Electrical Discharge

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        1 - The effect of mixed electric field on characteristic of ozone generation in a DBD plasma source
        Pourya Seyfi Mehrdad Rezaei Golghand Saeed Ghasemi Hamid Ghomi
        AbstractIn this paper, we have presented a new power supply structure for ozone generation in a dielectric barrier discharge reactor, so that a high-frequency pulse electric field is applied on the reactor simultaneously with a low-frequency sinusoidal electric field, r أکثر
        AbstractIn this paper, we have presented a new power supply structure for ozone generation in a dielectric barrier discharge reactor, so that a high-frequency pulse electric field is applied on the reactor simultaneously with a low-frequency sinusoidal electric field, referred as mixed electric field. In this study, the effect of mixed electric field variation on ozone production efficiency has been investigated and increasing effects on ozone production have been observed when the reactor temperature decreases. This performance has been achieved by modifying the mechanism of electrical discharge and decrease in filamentary discharge in plasma. By examining the spectral lines of atomic emission spectroscopy, the highest peak of the oxygen (O I) spectral lines was observed in the spectrum of the mixed electric field structure. Also by qualitative comparison of the spectral lines, the lowest intensity for the oxygen (O II) spectral lines was observed in this spectrum. Practically, this technique allows us to achieve higher ozone efficiency with less electrical power. Eventually, with the electric field mixing, we were able to achieve a 4.5% efficiency with 7.7 g/h of ozone generation at 2 kW/m2 with 2 L/min injector oxygen. In addition, by electric field mixing, we were able to reduce the reactor temperature from 66 to 41 °C. تفاصيل المقالة
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        2 - میزان تخریب رنگ آلی متیل اورانژ توسط پلاسما ولتاژ بالای اسپارک
        فائزه رحیمی مهدی مومنی منصور عرب چم جنگلی
        زمینه و هدف: یکی از مهمترین معضلات جامعه مدرن آلودگی آب‌ها می‌باشد، از جمله این آلاینده‌ها، رنگ‌های آلی موجود در پساب کارخانه‌های صنعتی هستند که حذف آن‌ها بسیار حائز اهمیت است. هدف از این پژوهش ارائه راهکاری برای از بین بردن رنگ آلی متیل اورانژ موجود در فاضلاب‌های صنایع أکثر
        زمینه و هدف: یکی از مهمترین معضلات جامعه مدرن آلودگی آب‌ها می‌باشد، از جمله این آلاینده‌ها، رنگ‌های آلی موجود در پساب کارخانه‌های صنعتی هستند که حذف آن‌ها بسیار حائز اهمیت است. هدف از این پژوهش ارائه راهکاری برای از بین بردن رنگ آلی متیل اورانژ موجود در فاضلاب‌های صنایع توسط پلاسمای اسپارک می‌باشد. روش بررسی: در این پژوهش، میزان رنگ‌زدایی و تخریب محلول متیل اورانژ با استفاده از روش تخلیه الکتریکی پلاسمایی در سطح مشترک آب-گاز در تاریخ مهر سال 99 مورد بررسی قرار گرفت. دستگاه تخلیه الکتریکی استفاده شده در کار حاضر از نوع جرقه با ساختار الکترودی سوزن-صفحه، ولتاژ موثر KV12-1 و فرکانس ثابت KHz13 می‌باشد. یافته‌ها: نتایج نشان می‌دهد که رنگ‌زدایی و تخریب محلول رنگی متیل‌اورانژ در سطح مشترک آب-گاز هوا آغاز می‌شود که این می‌تواند ناشی از از تابش اشعه فرا بنفش و تولید رادیکال‌ OH و گونه بسیار واکنش‌پذیر H2O2 در سطح مشترک آب-گاز هوا باشد. اثرات پارامترهای دستگاه تخلیه از جمله ولتاژ اعمالی، فاصله بین الکترودها، زمان تیمار و همچنین اثرات شیمیایی محلول مانند غلظت ماده رنگی تأثیر به سزایی در میزان رنگزدایی دارد. نتایج نشان داد که با افزایش ولتاژ و افزایش زمان تیمار میزان رنگ‌زدایی افزایش یافته، و همچنین با ثابت نگه داشتن توان الکتریکی دستگاه میزان رنگ زدایی با افزایش غلظت کاهش می‌یابد. با انتخاب فاصله بین الکترودها به اندازه cm 2 ما شاهد بیش‌ترین میزان رنگ‌زدایی در محلول بودیم. بحت و نتیجه‌گیری: نتایج حاکی از آن است که در این راکتور pH اولیه تأثیر قابل‌توجهی بر میزان رنگ‌زدایی ندارد. همچنین بیش‌ترین میزان رنگ‌زدایی به مقدار 8/99 درصد در غلظت ppm30، ولتاژ موثر KV10، فاصله الکترودی cm2، pH برابر 3 و زمان 30 دقیقه رخ داده است. تفاصيل المقالة
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        3 - Effect of the Micro Wire-EDM Process Parameters on the Recast Layer in the Molybdenum Micromachining
        Mohammad Tahmasebipour Y. Tahmasebipour A. Shabani M. Boujari Aliabadi
        The Micro wire electrical discharge machining (Micro wire-EDM) process is a modern machining process with various applications in manufacturing micro-parts. The recast layer remaining on the machined surfaces is an inevitable complication of this process. This layer can أکثر
        The Micro wire electrical discharge machining (Micro wire-EDM) process is a modern machining process with various applications in manufacturing micro-parts. The recast layer remaining on the machined surfaces is an inevitable complication of this process. This layer can subsequently affect the machined parts performance. To optimize the recast layer in the micro wire-EDM of the molybdenum microparts, effect of the process parameters on the distribution amplitude of the recast layer was investigated using the Taguchi method. The obtained results showed that the optimal levels of the micro wire-EDM process parameters for achieving the optimal distribution amplitude of the recast layer are as follows: spark pulse-on time of 0.2 μs, cutting speed of 7 mm/min, process voltage of 17 V, and wire tension of 0.45 kg. Also the importance order of the effect of the process parameters on the distribution amplitude of recast layer is as follows: spark pulse-on time, process voltage, cutting speed, and wire tension. تفاصيل المقالة
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        4 - Micro Wire Electrical Discharge Machining of MEMS Structures with Optimized Dimensional Deviation
        Mohammad Tahmasebipour Younes Tahmasebipour Ali Vafaie
        Metal-based microelectromechanical systems are widely used in applications such as micro-energy harvesters, micro-heat exchangers and micro-electromagnetic that require high strength and flexibility. In the fabrication of such systems, micro wire electrical discharge ma أکثر
        Metal-based microelectromechanical systems are widely used in applications such as micro-energy harvesters, micro-heat exchangers and micro-electromagnetic that require high strength and flexibility. In the fabrication of such systems, micro wire electrical discharge machining (MicroWEDM) is majorly used. This paper studies the effect of the MicroWEDM process parameters on the dimensional deviation of machined MEMS structures including microcantilevers and micro-beams using the Taguchi method. Using optimal levels of the parameters including pulse duration (0.8 µs), cutting speed (8.4 mm/min), voltage (17 V) and wire tension (0.5 kg), the dimensional deviation is reduced about 8.65 times compared with the average of experiments results. The order of effect importance of the process parameters on the dimensional deviation of microstructures obtained by the ANOVA analysis of S/N ratios is as follows: pulse duration, wire tension, process voltage and cutting speed. Dimensional deviation of the micro-features was reduced to 1 μm using the optimal levels of the process parameters. تفاصيل المقالة
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        5 - Investigation of the TiO2/SiC/SiO2 Coating Effect On the Wear Rate of Needle Graphite Electrode by using Electrical Discharge Machining
        Hossein Alian Moghadam majid jabbari Saeed Daneshmand Saeid Rasouli Jazi Arezoo Khosravi
        Needle graphite electrodes are one of the main parts used in electric arc furnaces. These electrodes have a significant impact on melt quality and product quality, and their consumption is one of the most important parameters of steel production cost in EAF furnaces. Th أکثر
        Needle graphite electrodes are one of the main parts used in electric arc furnaces. These electrodes have a significant impact on melt quality and product quality, and their consumption is one of the most important parameters of steel production cost in EAF furnaces. Therefore, reducing the consumption of needle graphite electrodes in these furnaces is very important. The main reasons for continuous use of needle graphite electrodes in arc furnaces are oxidation of the sidewalls and sublimation of their tips, and many solutions have been proposed to reduce them. In the present study, the effect of coating consisting of TiO2/SiC/SiO2 elements on the wear rate of the needle graphite electrode in the sublimation state is investigated using EDM (Electrical Discharge Machining- Spark device). For this purpose, the effect of voltage, current, pulse on time and pulse off time on the electrode wear rate are investigated and in this regard, Taguchi design method has been used to reduce the number of experiments. Based on the test results, TiO2/SiC/SiO2 coating reduces the wear rate of the needle graphite electrode due to sublimation. تفاصيل المقالة
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        6 - Micro Electropolishing of the MEMS Metallic Structures Fabricated by the Micro WEDM Process
        Mohammad Tahmasebipour Younes Tahmasebipour Mahya Boujari Aliabadi Shadi Ebrahimi
        In this study, the micro electro-polishing method was employed to improve the surface quality of microbeams machined by the micro WEDM method and to remove the recast layer. This approach changes the dimensions of the microbeams, as a result of the electrochemical corro أکثر
        In this study, the micro electro-polishing method was employed to improve the surface quality of microbeams machined by the micro WEDM method and to remove the recast layer. This approach changes the dimensions of the microbeams, as a result of the electrochemical corrosion, in addition to the elimination of the recast layer. To diminish the impact of this process on the dimensional deviation of the fabricated microbeams, the influence of the micro electro-polishing process parameters such as voltage, duration, cathode diameter, and electrolyte composition on the dimensional deviation of microbeams was studied using the Taguchi method. The optimum values of process parameters were determined by the S/N ratios analysis, and the order of parameters importance was determined through analysis of variance of the S/N ratios. It was found that the optimal levels of the process parameters are voltage of 2 V, process duration of 20 s, cathode diameter of 50 mm, and electrolyte composition of 25-5-40 ml (sulfuric-phosphoric-water) within the range of experiments. By using the optimum values of the parameters, the dimensional deviations were found to be 5.23 times lower compared to the average of the results. The importance of process parameters was found to follow this order: electropolishing duration, electrolyte composition, cathode diameter, and process voltage. تفاصيل المقالة
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        7 - Investigating the Effect of Electrical Discharge Process Input Parameters on Mechanical Properties of Aluminum Surface
        Hadi Eivazi bagheri Hamid Gorji Mohammad Reza Shabgard mohamad Bakhshi-Jooybari
        One of the important parameters in electrical discharge machining is the presence of micro cracks on the workpiece surface (recast layer). Therefore, the aim of this study was to investigate the possibility of increasing the mechanical properties of aluminum surface by أکثر
        One of the important parameters in electrical discharge machining is the presence of micro cracks on the workpiece surface (recast layer). Therefore, the aim of this study was to investigate the possibility of increasing the mechanical properties of aluminum surface by alloying elements (copper and nickel) diffusion to the recast layer and thus removing surface micro cracks. For this purpose, pulse on time and pulse current in with and without ultrasonic vibration have been considered as input parameters and the presence of surface micro cracks has been investigated using microscopic images. Also, the yield stress of the surface layer was calculated using the surface micro hardness. Based on the obtain results, surface without micro cracks has been created on the aluminum surface due to the diffusion of copper and nickel into the workpiece surface which increased aluminum surface yield strength from 90MPa to 280MPa without ultrasonic vibrations and to 310MPa while applying ultrasonic vibrations. In other words, ultrasonic vibrations cause an average of 20% increase in surface layer yield strength. In addition, according to the wear test, in the case of using ultrasonic vibration, improving the mechanical properties of the surface has caused thinner grooves on the aluminum surface. تفاصيل المقالة
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        8 - Using design of experiments approach and simulated annealing algorithm for modeling and Optimization of EDM process parameters
        Masoud Azadi Moghaddam Farhad Kolahan Meysam Beytolamani
        The main objectives of this research are, therefore, to assess the effects of process parameters and to determine their optimal levels machining of Inconel 718 super alloy. gap voltage, current, time of machining and duty factor are tuning parameters considered to be st أکثر
        The main objectives of this research are, therefore, to assess the effects of process parameters and to determine their optimal levels machining of Inconel 718 super alloy. gap voltage, current, time of machining and duty factor are tuning parameters considered to be study as process input parameters. Furthermore, two important process output characteristic, have been evaluated in this research are material removal rate (MRR) and surface roughness (SR). Determination of a combination of process parameters to minimize SR and maximize MRR is the objective of this study. In order to gather required experimental data, design of experiments (DOE) approach, has been used. Then, statistical analyses and validation experiments have been carried out to select the best and the most fitted regression models. In the last section of this research, simulated annealing (SA) algorithm has been employed for optimization of the EDM process performance characteristics. A set of verification tests is also performed to confirm the accuracy of the proposed optimization procedure in determining the optimal levels of machining parameters. The results indicate that the proposed modeling technique and SA algorithm are quite efficient in modeling and optimization of EDM process parameters. تفاصيل المقالة
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        9 - Improving the surface wear resistance of aluminum by electrical discharge process
        Hadi eivazi bagheri Mohammad Reza Shabgard Hamid Gorji salman nourouzi
        In this study electrical discharge process was used to increase surface wear resistance of pure aluminum. Pulse-on-time and pulse current were considered as input parameters of the electrical discharge process. Experimental results reveal that the electrical discharge p أکثر
        In this study electrical discharge process was used to increase surface wear resistance of pure aluminum. Pulse-on-time and pulse current were considered as input parameters of the electrical discharge process. Experimental results reveal that the electrical discharge process is a successful method for improving the surface wear resistance of aluminum, so that this method has greatly increased the surface wear resistance of aluminum parts. Results indicate that with increase input parameters (pulse-on-time and pulse current) weight loss of the aluminum specimens is reduced and the wear resistance increases. The XRD analysis demonstrated that Al3Ni2 and AlCu intermetallic compound and Al4C3 were formed on alloyed surface. The presence of these compounds and hard particles at the surface increases the wear resistance. Also, friction coefficient measurements show that, after electrical discharge process and improving surface wear resistance, the friction coefficient slightly increased due to the presence of hard particles on the alloyed surface. تفاصيل المقالة
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        10 - Investigation of the Impact of the Alumina Powder Presence in Dielectric on Electrical Discharge Machining Parameters of A413 Aluminum Workpiece using Taguchi's Experiment Design, Signal-to-noise Analysis, and Total Normalized Quality Loss
        Mojtaba Shahbazi Dastjerdi Ali Mokhtarian Mojtaba Rahimi
        This study aimed to scrutinize the impact of the electrical discharge machining (EDM) parameters of A413 alloy for two cases of dielectric, one with alumina powder and one without, using Taguchi's experiment design method. The completed studies regarding the EDM of the أکثر
        This study aimed to scrutinize the impact of the electrical discharge machining (EDM) parameters of A413 alloy for two cases of dielectric, one with alumina powder and one without, using Taguchi's experiment design method. The completed studies regarding the EDM of the metal-base composites reveal that insufficient research work has been carried out on this composite material. In this research, by using Taguchi's experiment design and through the simultaneous analysis of Total Normalized Quality Loss (TNQL) and Signal-to-Noise ratio (S/N) of the outputs, the impacts of the current intensity, voltage, pulse on-time, and pulse off-time on the material removal rate (MRR), surface roughness (SR), and tool wear rate (TWR) were investigated. The results showed that the use of 3g/L of alumina powder in kerosene dielectric averagely led to a 6.47%, 9.14%, and 19.40% reduction in MRR, SR, and TWR, respectively. Also, the results acquired using TNQL and S/N analyses demonstrated that the optimum experiment was composed of the third level of voltage (A3), the first level of current (B1), the first level of pulse on-time (C1), and the third level of pulse-off time (D3). It was concluded that the current intensity had the greatest impact on the MRR and SR. However, the pulse-on time had the greatest influence on the TWR. It was also observed that the MRR declined by adding 3g/L aluminum oxide powder in the kerosene dielectric which in turn caused a reduction in the SR and the TWR compared to the case of the kerosene dielectric without powder. تفاصيل المقالة
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        11 - Intelligent Knowledge Based System Approach for Optimization of Design and Manufacturing Process for Wire-Electrical Discharge Machining
        Morteza Sadegh Amalnik
        Wire electrical discharge machining (WEDM) is a method to cut conductive materials with a thin electrode that follows a programmed path. The electrode is a thin wire. Typical diameters range from .004" - .012" (.10mm - .30mm) although smaller and larger diameters are av أکثر
        Wire electrical discharge machining (WEDM) is a method to cut conductive materials with a thin electrode that follows a programmed path. The electrode is a thin wire. Typical diameters range from .004" - .012" (.10mm - .30mm) although smaller and larger diameters are available. WEDM is a thermal machining process capable of accurately machining parts with varying hardness or complex shapes. WEDM process is based on electrical discharge machining (EDM) sparking phenomenon, utilizing the widely accepted non-contact technique of material removal. The hardness of the work piece material has no detrimental effect on the cutting speed. There is no physical contact between the wire and the part being machined. Rather, the wire is charged to a voltage very rapidly. This wire is surrounded by deionized water. When the voltage reaches the correct level, a spark jumps the gap and melts a small portion of the work piece. The deionized water cools and flushes away the small particles from the gap. This paper addresses the concept of WEDM and its parameters and development of an intelligent knowledge based system (IKBS) for WEDM in computer based concurrent engineering environment. The system links with a feature based CAD system in order to extract design data. The system is linked with databases. The machining cycle time, cost, material removal rate, and surface roughness of hole making are estimated for each selected design feature. The system provides useful information for product designers and manufacturing engineers and also advises manufacturing engineers to select optimum machining parameters. تفاصيل المقالة
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        12 - An experimental analysis and optimization of machining rate and surface characteristics in WEDM of Monel-400 using RSM and desirability approach
        Vinod Kumar Vikas Kumar Kamal Kumar Jangra
        In the present work, an experimental investigation on wire electrical discharge machining (WEDM) of Monel-400 has been presented. Monel-400 is a nickel–copper-based alloy, mostly employed in ships and corrosion-resisting applications. Four input WEDM parameters na أکثر
        In the present work, an experimental investigation on wire electrical discharge machining (WEDM) of Monel-400 has been presented. Monel-400 is a nickel–copper-based alloy, mostly employed in ships and corrosion-resisting applications. Four input WEDM parameters namely discharge current (Ip), pulse-on time (Ton), pulse-off time (Toff) and servo voltage (SV) have been investigated and modeled for two performance characteristics namely machining rate (MR) and surface roughness (SR). Effect of WEDM parameters has been discussed using response surface graphs. Using analysis of variance, quadratic model is found significant for MR while two factors interaction (2FI) model has been suggested for SR. To optimize multi-performance characteristics, desirability function has been employed. Corresponding to highest desirability, the optimal combination of discharge parameters is Ip: 103A; Ton: 113μs; Toff: 37μs and SV: 50V. The effect of discharge energy on surface morphology has also been examined. High discharge energy increases the extent of surface damage and results in large size and overlapped craters on machined surface. Low discharge energy and high value of Toff result in minimum defects on machined surface. Trim cutting operations were performed at low discharge energy using different wire offset values. Result shows that surface finish can be improved significantly after a single trim cut irrespective of high discharge energy in rough cut. تفاصيل المقالة
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        13 - Multi-objective optimization in WEDM of D3 tool steel using integrated approach of Taguchi method & Grey relational analysis
        Anand S. Shivade Vasudev D. Shinde
        In this paper, wire electrical discharge machining of D3 tool steel is studied. Influence of pulse-on time, pulse-off time, peak current and wire speed are investigated for MRR, dimensional deviation, gap current and machining time, during intricate machining of D3 tool أکثر
        In this paper, wire electrical discharge machining of D3 tool steel is studied. Influence of pulse-on time, pulse-off time, peak current and wire speed are investigated for MRR, dimensional deviation, gap current and machining time, during intricate machining of D3 tool steel. Taguchi method is used for single characteristics optimization and to optimize all four process parameters simultaneously, Grey relational analysis (GRA) is employed along with Taguchi method. Through GRA, grey relational grade is used as a performance index to determine the optimal setting of process parameters for multi-objective characteristics. Analysis of variance (ANOVA) shows that the peak current is the most significant parameters affecting on multi-objective characteristics. Confirmatory results, proves the potential of GRA to optimize process parameters successfully for multi-objective characteristics. تفاصيل المقالة
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        14 - Effect of Impulse Voltage on Partial Discharge of Oil and Paper - Oil Insulators Containing Air Cavity
        Seyed Mohammad Hassan Hosseini Roya Shmsali
        In power systems, usually by lightning strikes or switching operation, impulse voltage is produced. This paper reviews the effect of high impulse voltage on the PD parameters. In recent years, numerous studies on PD in the insulation, under the impulse has been done. De أکثر
        In power systems, usually by lightning strikes or switching operation, impulse voltage is produced. This paper reviews the effect of high impulse voltage on the PD parameters. In recent years, numerous studies on PD in the insulation, under the impulse has been done. Despite the use of power equipment and tools, switching impulse is created in the system. So, studies on PD activity with the initiation and end voltage PD in insulators have been investigated. However, the combination of PD characteristics with AC and impulse has not been studied in many studies so far. Unlike previous studies, in this paper, along with the impulse voltage, the AC voltage effects are also considered. On the other hand, dielectric characteristics show the quality of insulation in terms of the soundness or deterioration of equipment over time. The deterioration and aging of equipment can be due to electrical stresses such as alternating current PDs or transient stresses or due to environmental pressures and temperature or mechanical pressures. At this point, the effect of the PD alternating current (AC) on paper combination insulation oil dielectric frequency response equipment is investigated. In this review, a brief history of the performance of insulation against partial electrical discharge is addressed, and the finite element method software (Maxwell) is used to simulate partial electrical discharge for objects that are particularly sharp. تفاصيل المقالة
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        15 - Overview the Factors Affecting the Discharge of Contaminated Insulators and Intelligent Change Some of Them to Reduce the Discharge Intensity
        Yadullah Shafiei Faramarz Faghihi Amir Hossein Salemi Hossein Heydari
        In this article, the most important factors affecting the discharge characteristics of high voltage insulators will be investigated. The type and severity of pollution, geographical and climatic conditions such as fog, rain, and wind, as well as the height above sea lev أکثر
        In this article, the most important factors affecting the discharge characteristics of high voltage insulators will be investigated. The type and severity of pollution, geographical and climatic conditions such as fog, rain, and wind, as well as the height above sea level, and finally the appearance and constituent materials of insulators will be studied as the main influencing factors in causing flashes on their surface. In addition to its severity, the type of pollution has a great effect on the electrical properties of insulators. This issue is discussed in the first section of the article for common types of pollution with different severities. Furthermore , a mixture of pollutants in the air is also examined, and the insulation waste is also shown in the case of design only based on sea salt, which is the worst type of pollution.In the next part, a review on the influence of climatic and geographical conditions has been performed, and in it, the effect of frost, wind, humidity and altitude on the start of electric discharge is discussed as the most important of them.And finally, the effect of appearance and its associated parameters as well as the constituent materials of insulators in pollution conditions are the last factors that will be considered. In addition, in this study, it has been shown how by intelligently changing these two factors, leakage current and discharge intensity can be reduced in contaminated insulators and their premature aging and failure can be delayed. تفاصيل المقالة
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        16 - ﺑﺮرﺳﯽ تأثیر‬ ﭘﺎراﻣﺘﺮﻫﺎی ماشین‌کاری تخلیه‌الکتریکی، بر روی ماده مرکب پایه آلومینیوم 2024 با استفاده از تحلیل مقدار کل نرمال شده پارامترها (TNQL) و نسبت سیگنال به نویز (S/N)
        بهنام مسعودی سعید دانشمند
        مواد مرکب زمینه فلزی با توجه به نوع تقویت کننده قابلیت ماشینکاری متفاوتی دارند. ماده مرکب الومینیوم 2024 تقویت شده با اکسید آلومینیوم از جمله موادی می باشد که ماشینکاری آن به روش های سنتی فرسایش سریع ابزار را در پی دارد. این روش ماشینکاری دارای پارامترهای مختلفی می باشد أکثر
        مواد مرکب زمینه فلزی با توجه به نوع تقویت کننده قابلیت ماشینکاری متفاوتی دارند. ماده مرکب الومینیوم 2024 تقویت شده با اکسید آلومینیوم از جمله موادی می باشد که ماشینکاری آن به روش های سنتی فرسایش سریع ابزار را در پی دارد. این روش ماشینکاری دارای پارامترهای مختلفی می باشد. تنظیم بهینه پارامتر های ماشینکاری بر زمان، کیفیت محصول و سایش ابزار اثر مهمی دارد. در این تحقیق با استفاده از تحلیل مقدار کل نرمال شده پارامترها (TNQL) و نسبت سیگنال به نویز (S/N) همزمان خروجی‌ها به بررسی تاثیر پارانترهای ورودی ماشینکاری تخلیه الکتریکی شامل شدت جریان، ولتاژ، زمان روشنی و خاموشی پالس بر نرخ براده برداری، سایش ابزار و زبری سطح در حالت بدون پودر و پودر و دوران ابزار پرداخته شده است. نتایج نشان داد که شدت جریان بیشترین و بعد از آن زمان روشنی، زمان خاموشی پالس و در آخر ولتاژ مهمترین اثر را بر پارامتر های خروجی ماشینکاری دارند. استفاده از پودر اکسید آلومینیوم و دوران ابزار باعث افزایش گپ و ایجاد نیروی گریز از مرکز شده و ذرات را به سرعت از منطقه ماشینکاری دور می کند و نرخ براده برداری افزایش می یابد. استفاده از پودر آلومینیوم در برخورد با جرقه ها باعث ریز تر شدن جرقه ها شده و عمق نفوذ آنها را کم نموده و در نتیجه زبری سطح کاهش می یابد. نتایج حاصل از بهینه سازی در حالت بدون پودر و دوران ابزار ترکیب پارامترها به‌صورت A3B1C2D3 ودر حالت با پودر و دوران ترکیب پارامترها به‌صورت A1B1C2D3 را پیشنهاد می کند. تفاصيل المقالة
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        17 - ﺑﺮرﺳﯽ ماشین‌کاری تخلیه‌الکتریکی ماده مرکب آلومینیوم تقویت شده با نانو ذرات اکسید تیتانیوم
        علی اکبر لطفی سعید دانشمند
        نانو ذرات مورد استفاده در مواد مرکب زمینه فلزی دارای انواع مختلف و خواص فیزیکی، شیمیایی و مکانیکی متفاوتی می باشند که باعث بهبود سختی، مقاومت مکانیکی، سایش و خواص دمایی می شوند و قابلیت های ماشینکاری مواد را تغییر می دهند. در این تحقیق به بررسی پارامترهای ماشینکاری تخلی أکثر
        نانو ذرات مورد استفاده در مواد مرکب زمینه فلزی دارای انواع مختلف و خواص فیزیکی، شیمیایی و مکانیکی متفاوتی می باشند که باعث بهبود سختی، مقاومت مکانیکی، سایش و خواص دمایی می شوند و قابلیت های ماشینکاری مواد را تغییر می دهند. در این تحقیق به بررسی پارامترهای ماشینکاری تخلیه الکتریکی ماده مرکب الومینیوم تقویت شده با نانوذرات اکسید تیتانیوم پرداخته می شود. هدف از این تحقیق بررسی تاثیر شدت جریان، ولتاژ، زمان روشنی و خاموشی پالس و نانو ذرات اکسید تیتانیوم بر نرخ براده برداری، سایش ابزار و زبری سطح می باشد. از نفت سفید به عنوان دی الکتریک و الکترود مسی به عنوان ابزار و تجزیه و تحلیل واریانس برای اعتبار سنجی آزمایشگاهی استفاده می شود. نتایج نشان داد نانو ذرات سرامیکی اکسید تیتانیوم با توجه به ایتکه غیر هادی هستند تاثیر زیادی بر پارامترهای ماشینکاری ندارند و حین فرایند ماشینکاری تخلیه الکتریکی ذوب نمی شوند و شدت جریان و زمان روشنی بیشترین تاثیر بر نرخ براده برداری، سایش ابزار و زبری سطح دارند. با افزایش شدت جریان و زمان روشنی پالس سایش ابزار و زبری سطح زیاد شده و با افزایش زمان خاموشی پالس سایش ابزار کم می شود. به طور متوسط نرخ سایش الکترود ابزار در آلومینیوم 2024 تقویت شده با نانو ذرات اکسید تیتانیوم 5 درصد به میزان 46/3 درصد معادل 346/0گرم بیشتر از نمونه آلومینیوم 2024 از نظر وزنی است. تفاصيل المقالة
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        18 - بررسی و بهینه‌سازی تأثیر‬ پارامترهای ورودی بر نرخ براده برداری، نرخ سایش ابزار و زبری سطح در ماشین‌کاری تخلیه الکتریکی نانو کامپوزیت A356 تقویت‌شده با آلومینا
        محمدجواد حاج حسینی علی مختاریان مجتبی رحیمی بهنام مسعودی
        در این پژوهش، تأثیر پارامترهای ورودی ماشین‌کاری تخلیه الکتریکی بر روی نانو کامپوزیت A356 تقویت شده با 5/3% آلومینا (Al2O3)، با رویکرد طراحی آزمایش ها به روش تاگوچی بر مبنای آرایه متعامد L9 و تکنیک سطوح تکراری مورد بررسی و بهینه سازی قرار گرفت. پارامترهای ورودی این آزمای أکثر
        در این پژوهش، تأثیر پارامترهای ورودی ماشین‌کاری تخلیه الکتریکی بر روی نانو کامپوزیت A356 تقویت شده با 5/3% آلومینا (Al2O3)، با رویکرد طراحی آزمایش ها به روش تاگوچی بر مبنای آرایه متعامد L9 و تکنیک سطوح تکراری مورد بررسی و بهینه سازی قرار گرفت. پارامترهای ورودی این آزمایش ها شامل ولتاژ (دو سطحی)، شدت ‌جریان (سه سطحی)، زمان روشنی پالس (سه سطحی) و زمان خـاموشی پـالس (سه سطحی) در نظر گرفته شد. همچنین، پـارامترهای خروجی شامل نـرخ براده برداری از قطعه کار، نرخ سایش ابزار ماشین کاری و زبری سطح قطعه کار بودند. تحلیل نتایج و بررسی نمودار‌های سیگنال به نویز توسط نرم‌افزار انجام شد. همچنین با تعیین تابع زیان مقادیر نرمال شده کل پارامترهای خروجی بر مبنای ضرایب وزنی فرضی، سطح بهینه مربوط به هر پارامتر ورودی مشخص شد و با انجام آنالیز واریانس، میزان درصد سهم هر یک از پارامترهای ورودی در واریانس کل محاسبه شد. با توجه به نتایج حاصله، تأثیر‌گذارترین پارامتر ورودی بر روی نرخ براده برداری: زمان خاموشی پالس، بر روی نرخ سایش: ابزار شدت جریان و بر روی زبری‌ سطح: زمان روشنی پالس تعیین شد. علاوه بر این، سطح اول ولتاژ (80 ولت)، سطح اول شدت جریان (10 آمپر)، سطح اول زمان روشنی پالس (35 میکروثانیه) و سطح دوم زمان خاموشی پالس (70 میکروثانیه) به عنوان سطوح بهینه پارامترهای ورودی تعیین شدند. درصد سهم پارامترهای ورودی در واریانس کل نیز برای ولتاژ، شدت جریان، زمان روشنی پالس و زمان خاموشی پالس به ترتیب برابر 98/12، 96/20، 47/5 و 60/60 به دست آمدند. تفاصيل المقالة
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        19 - Investigation and optimization of the effect of input parameters on output parameters of electrical discharge machining of A356 nano-composite reinforced by SiC
        Amir Rahmani Ali Mokhtarian Mojtaba Rahimi
        In this study, the impact of input parameters of Electrical Discharge Machining (EDM) on A356 nano-composite reinforced by 6% SiC was investigated and optimized using Taguchi's method based on the L9 orthogonal array and duplicated levels method. We considered voltage, أکثر
        In this study, the impact of input parameters of Electrical Discharge Machining (EDM) on A356 nano-composite reinforced by 6% SiC was investigated and optimized using Taguchi's method based on the L9 orthogonal array and duplicated levels method. We considered voltage, current intensity, pulse on-time, and pulse off-time as the input parameters. Furthermore, material removal rate (MRR), tool wear rate (TWR), and surface roughness (SR) were taken into account as the output parameters. The analysis of results and examination of the signal-to-noise graphs (S/N) and analysis of variance (ANOVA) were performed using Minitab@16 software. Moreover, with the determination of the loss function of total normalized values of the output parameters based on assumed weight functions, the optimal level of each input parameter was established. Besides, the magnitude of contribution percentage of each of the input parameters in the total variance was computed through the variance analysis. According to the achieved results, the second level of the voltage (250 V), the first level of the current intensity (10 A), the third level of the pulse on-time (100 µs), and the first level of the pulse off-time (30 µs) were determined as the optimal input parameters. The contribution percentage of the input parameters for voltage, current intensity, pulse on-time, and pulse off-time was determined respectively to be 20.7, 62.06, 9.19, and 8.05. تفاصيل المقالة
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        20 - The Effect of Electrical Discharge Machining Parameters on Alloy DIN 1.2080 Using the Taguchi Method and Optimal Determinant
        پویان صدر امین کلاه دوز علی افتخاری
        Electrical discharge machining process, is one of the most widely used methods for machining, the electrically conductive parts. In this way the tool is not in contact with the workpiece and the hardness of workpiece does not affect the machining speed. In Electrical Di أکثر
        Electrical discharge machining process, is one of the most widely used methods for machining, the electrically conductive parts. In this way the tool is not in contact with the workpiece and the hardness of workpiece does not affect the machining speed. In Electrical Discharge Machining process, selection of the correct machining parameters are effective in final cost and the quality of the products. The special application of this alloy in various industries including tooling industry is attributed to its high hardness and wear resistance. The DIN 1.2080 steel at low temperature has a high wear resistance. Its hardness depth is high and it is suitable for machining at low temperature. In this paper, the effect of the type and setting parameters and determination of optimal levels in of electrical discharge machining of alloy DIN 1.2080 using the Taguchi method and optimal determinant is examined The desired setting parameters including gap voltage, current intensity, on time and off time. The material removal rate and surface roughness of produced parts as the output characteristic of the study were investigated. Results showed that the spark current is more effective on the output parameter (more than 65% on material removal rate and more than 48% on a surface roughness), Other effective parameters are pulse on time, pulse off time and voltage changes, respectively. Higher current and pulse on time values and lower voltage and pulse off time values result in high MRR and low SR تفاصيل المقالة
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        21 - Optimization of Material Removal Rate in Electrical Discharge Machining Alloy on DIN1.2080 with the Neural Network and Genetic Algorithm
        مسعود عظیمی امین کلاه دوز سید علی افتخاری
        Electrical discharge machining process is one of the most Applicable methods in Non-traditional machining for Machining chip in Conduct electricity Piece that reaching to the Pieces that have good quality and high rate of machining chip is very important. Due to the rap أکثر
        Electrical discharge machining process is one of the most Applicable methods in Non-traditional machining for Machining chip in Conduct electricity Piece that reaching to the Pieces that have good quality and high rate of machining chip is very important. Due to the rapid and widespread use of alloy DIN1.2080 in different industry such as Molding, lathe tools, reamer, broaching, cutting guillotine, etc. Reaching to optimum condition of machining is very important. Therefore the main aim in this article is to consider the effect of input parameter such voltage, Current strength, on-time pulse and off-time pulse on the machining chip rate and optimizing this in the electrical discharge machining for alloy DIN1.2080. So to reach better result after doing some experiments to predict and optimize the rate of removing chip, neural network method and genetic algorithm are used. Then optimizing input parameters to maximize the rate of removing chip are performed. In this condition, by decreasing time, the product cost is decreased. Optimum parameters in this experiment in this condition are obtained under Current strength 20 ampere, 160 volt, on-time pulse 100 micro second and off-time pulse 12 micro second that is obtained 0.063 cm3/min as rate of machining chip. After doing experiment, surveying the level of error and its accuracy are evaluated. According to the obtained error value that is about 5.18%, used method is evaluated for genetic algorithm تفاصيل المقالة