International Journal of Emerging Technology and Advanced Engineering Website: www.ijetae.com (ISSN 2250-2459, ISO 9001:2008 Certified Journal, Volume 3, Issue 4, April 2013) 1 Optimization of EDM process parameters: A Review Vikram Singh 1 , S.K.Pradhan 2 1 M.E. Student, Mechanical Engg. Department, NITTTR Bopal-462002, INDIA 2 Associate Professor and Head, Mechanical Engg. Department, NITTTR Bopal-462002, INDIA 1 vikram.mech89@gmail.com 2 spradhan@nitttrbpl.ac.in Abstract — Electrical Discharge Machining performance is generally evaluated on the basis of Material Removal Rate (MRR), Tool Wear Rate (TWR), Relative Wear Ratio (RWR) and Surface Roughness (SR). The important EDM machining parameters affecting to the performance measures of the process are discharge current, pulse on time, pulse off time, arc gap, and duty cycle [9]. A considerable amount of work has been reported by the researchers on the measurement of EDM performance on the basis of MRR, TWR, RWR, and SR for various materials. Several approaches are proposed in the literature to solve the problems related with optimization of these parameters. It is felt that a review of the various approaches developed would help to compare their main features and their relative advantages or limitations to allow choose the most suitable approach for a particular application and also throw light on aspects that needs further attention. In view of above, this paper presents a review of development done in the optimization of EDM related process parameters. Keywords— EDM, MRR, EWR, SR, RSM, Taguchi. I. INTRODUCTION Electrical Discharge Machining (EDM) is an important manufacturing process for machining hard metals and alloys [2]. This process is widely used for producing dies, molds, and finishing parts for aerospace, automotive, and surgical components [3]. The process is capable of getting required dimensional accuracy and surface finish by controlling the process parameters [4]. EDM performance is generally evaluated on the basis of Material Removal Rate (MRR), Tool Wear Rate (TWR), Relative Wear Ratio (RWR), and Surface Roughness (SR) [3]. The important EDM parameters affecting to the performance measures of the process are discharge current, pulse on time, pulse off time, arc gap, and duty cycle [9].In EDM, for optimum machining performance measures, it is an important task to select proper combination of machining parameters [13]. Generally, the machining parameters are selected on the basis of operator’s experience or data provided by the EDM manufactures. When such information is used during Electrical Discharge Machining, the machining performance is not consistent. Data provided by the manufacturers regarding the parameter settings is useful only for most commonly used steels. Such data is not available for special materials like Maraging steels, ceramics, and composites. For these materials, experimental optimization of performance measures is essential. Optimization of EDM process parameters becomes difficult due to more number of machining variables and slight changes in a single parameter significantly affect the process. Thus, it is essential to understand the influence of various factors on EDM process. Analytical and statistical methods are used to select best combination of process parameters for an optimum machining performance. Different author use different combination of process parameters. They analyze the experimental data by plotting Interaction graphs, Residual plots for accuracy and Response curves. Some other methods used by different author for analysis of Taguchi’s DOE data related to Electrical Discharge Machining (EDM) and Wire Electrical Discharge Machining (WEDM) are Regression analysis, Response Surface Methodology, Central Composite Design (CCD), Feasible-Direction Algorithm, SA algorithm, Pareto, Artificial Bee Colony (ABC), Grey Relational Analysis, Genetic Algorithm, Fuzzy clustering, Artificial Neural Network, Tabu-Search Algorithm, Principle component method etc. Most of the author used L27 Orthogonal Array. Generally the effect of Pulse ON time, Pulse OFF time, Spark gap set Voltage, Peak current, Flushing Pressure, Work piece height, wire tension and wire feed on the material removal rate, surface roughness, kerf and gap current is investigated.