Evaluation of material removal rate and electrode wear rate in die sinking EDM with tool material Al_2O_3/Cu composite through Taguchi method

摘要

This paper investigates the effect of electric discharge machining (EDM) die-sink process parameters on electrode wear rate (EWR) and material removal rate (MRR) of aluminium oxide/copper (Al_2O_3/CU) composite using Taguchi method. Four EDM process parameters namely peak current, voltage, pulse on time and pulse off time at two levels was taken under consideration. Taguchi's L_8 orthogonal array was used for experimental run. The signal-to-noise ratio, analysis of variance, 3-D surface plots and contour plots were used to examine which parameter significantly affects EWR and MRR. Confirmation test was conducted to ensure the validity of test results. The scanning electron microscope (SEM) and energy dispersive X-ray (EDX) were used for surface morphology and composition analysis. The results indicate that the peak current is the most influential parameter that affects EWR and MRR. The processing condition of minimum EWR/MRR ratio is well agreed with Taguchi's optimal condition.