Showing papers by "T. Muthuramalingam published in 2013"
TL;DR: In this paper, the machining characteristics of AISI 202 stainless steel have been investigated in thermal erosion process using taguchi method based experiments with conventional and modified pulse generators using electric discharge machining.
Abstract: In this study, the machining characteristics of AISI 202 stainless steel have been investigated in thermal erosion process. Taguchi method based experiments have been conducted with conventional and modified pulse generators using electric discharge machining. Material removal rate (MRR) and surface roughness were taken to evaluate performance of process. Gap voltage, discharge current, and duty factor have been chosen as input parameters to access the machinability. The efficacy of pulse generators in thermal erosion process is determined by high material removing property and better surface finish. Since this machining process has stochastic nature, conventional RC relaxation pulse generator and transistor pulse train generator could not satisfy both the two requirements. It is proved that modified ISO current pulse generator could produce better surface finish with high MRR than conventional pulse generators in thermal erosion process.
84 citations
TL;DR: In this paper, the effects of tool electrode on machinability of AISI 202 stainless steel were investigated using different combinations of electrical input parameters, and it was observed that tool properties of tool electrodes could have an influence on machining characteristics in spark erosion process.
Abstract: High-strength materials can be easily machined by spark erosion process to obtain complex shapes. The discharge energy can be characterized by the current flowing through the dielectric medium in spark erosion process during the machining. The performance measures such as workpiece erosion, tool electrode erosion, and surface finish can be modified by the properties of tool electrode material. This current is determined by the conductivity of the tool electrode material. The erosion process has been experimentally investigated to analyze the effects of tool electrode on machinability of AISI 202 stainless steel in the present study. Copper, brass, and tungsten carbide have been used as the tool electrode with different combinations of electrical input parameters. From the results, it is observed that tool properties of tool electrode material could have an influence on machining characteristics in spark erosion process. Copper tool could give higher material removal rate, whereas tungsten carbide could pr...
49 citations
TL;DR: In this article, a modified iso-energy pulse generator has been proposed to improve the surface quality with higher material removal rate (MRR), which has been observed that the modified iso energy pulse generator had removed 5% more material from the work piece than the conventional transistor pulse generator.
Abstract: It is important to improve the process mechanism of the electrical discharge machining (EDM) to achieve fine surface quality due to its stochastic nature. The conventional transistor pulse generator produces higher surface roughness in electro-erosion process. In the present study, an attempt has been made to investigate the influence of iso (identical) energy pulse generator on machining characteristics of erosion process. The modified pulse generator can produce uniform discharge energy distribution which is characterized by variable pulse width modulation adopted with the current sensor. The proposed pulse generator can control the ionization path diameter of insulator medium by varying the pulse duration. From the experimental results, it has been observed that the modified iso energy pulse generator has improved the surface quality with higher material removal rate (MRR). The iso energy pulse generator has removed 5% more material from the work piece than the conventional transistor pulse generator. ...
35 citations
01 Dec 2013
TL;DR: In this paper, a taguchi-grey relational approach based multi response optimization has been used to maximize material removal rate and to minimize surface roughness in electrical discharge machining process.
Abstract: In modern machining process, optimization technique is used to find the optimal values of input parameters and the effect of those parameters on response variables. If response parameters are more than one, Taguchi method of optimization may give different set of optimal levels for each response. In the present study, Taguchi-grey relational approach based multi response optimization has been used to maximize material removal rate and to minimize surface roughness in electrical discharge machining. Electrical process parameters such as gap voltage, peak current and duty factor have been used as input parameters. It has been found that peak current has most influent nature in electrical discharge machining process. Optimal combination of input parameter to acquire better responses has been found with multi response optimization using Taguchi-grey relational analysis.
29 citations
TL;DR: In this paper, the authors investigated the contribution of electrical process parameters on machining characteristics and optimal combination of those parameters using Taguchi-data envelopment analysis-based ranking method, and revealed that electrical parameters have significant role in EDM process and the optimal values have been found using proposed multi-response methodology.
Abstract: Since electrical process parameters are determining the machining characteristics of electrical discharge machining (EDM), it is important to find the optimum values of those parameters and contribution of each parameter. As the process involves more than one response parameter, it is needed to implement the multi-response optimization methodology. AISI 202 stainless steel was selected as work piece material, whereas copper, brass, and tungsten carbide were selected as tool materials. The experiments were conducted with different levels of input factors such as gap voltage, discharge current, and duty factor based on L9 orthogonal table. The purpose of this study is to investigate the contribution of electrical process parameters on machining characteristics and optimal combination of those parameters using Taguchi-data envelopment analysis-based ranking method. From the results, it is revealed that electrical parameters have significant role in EDM process and the optimal values have been found using proposed multi-response methodology.
11 citations
TL;DR: In this article, an ISO duration current pulse generator has been designed and developed for obtaining good surface finish in EDM process, and it is found that modified ISO pulse generator could produce better surface finish.
Abstract: Electrical discharge machining (EDM) is good example for mechatronics application, in which, the material is removed by thermal energy. The thermal energy is produced by applying DC pulses between tool electrode and work piece. The characteristics of DC pulses are determined by the pulse generators. Due to its high material removal nature, transistor pulse train generator is commonly employed. Since EDM process has stochastic nature, transistor pulse generator produces high surface roughness. To produce better product quality, a constant discharging current is needed throughout the process. In this research, an ISO duration current pulse generator has been designed and developed for obtaining good surface finish. It is found that modified ISO pulse generator could produce better surface finish.
6 citations
TL;DR: From the results, it is proved that the modified transistor pulse train generator could produce higher surface finish than existing transistor pulse generator with considerable amount.
Abstract: The efficacy of pulse generator in electrical discharge machining is characterised by material removal rate and surface roughness. Due to its low frequency operation, RC relaxation pulse generator could produce lower material removal rate and lower surface roughness than transistor pulse train generator. Since transistor pulse generator could produce larger crater volume throughout the process, it could made higher surface roughness with higher material removal rate. By producing smaller crater volume during finishing stage, surface finish can be improved. The main objective of this study is to improve surface finish by enhancing the process mechanism in thermal erosion process. In the present study, a modified form of the transistor pulse generator approach has been developed. The effects of the pulse generators on the machining characteristics has been experimentally evaluated using Taguchi L9 orthogonal table and analysed in the EDM process. Gap voltage, discharge current and duty factor has been chosen as input variables to evaluate the material removal rate. From the results, it is proved that the modified transistor pulse train generator could produce higher surface finish than existing transistor pulse generator with considerable amount.
2 citations