Abstract

Electrical discharge machining (EDM) is one of the most extensively used non-traditional material removal processes for difficult-to-cut materials. The full potential of the EDM process has not yet been exploited due to its complicated discharge mechanism. Though a lot of research has been done to improve the process performance, optimal selection of process parameters for the best performance measures still remains a challenge. Parameter optimization is one of the techniques used in manufacturing processes to achieve best manufacturing conditions, which is an essential need for industries towards manufacturing of higher quality products at lower cost. In this paper, the cutting of hot work tool steel 2714 using electro discharge machining process with copper and graphite electrodes has been investigated. In this work L₂₇ (3*4) orthogonal array based on the Taguchi experimental design is utilized to plan the experiments. Raw data is assessed by the Analysis of Variance (ANOVA) to find optimal conditions for response parameters. The main machining parameters such as pulse-on time, pulse-off time, discharge current, average machining voltage are chosen to determine the EDM response parameters such as material removal rate, surface roughness and gap size. Response tables and graphs are used to find the optimal parameter levels in the EDM process.

Key words: Electrical discharge machining (EDM), tool steel 2714, Taguchi approach, material removal rate, surface roughness and gap size.