Experimental Study and Optimization of Wire-Electrical Discharge Machined WC-15%Co Metal Matrix Composites

Abstract

Wire Electrical discharge Machining plays an important role in the field of hard, difficult to machine materials like metal matrix composites. Machining process must keep pace with material development. For electrically conductive materials wire electro discharge machining is a viable option due to high accuracy, precision, and ability to achieve complex, intricate shaped profiles on even thin works. Due to thermo-electric nature it is a stochastic process in nature. To simplify the difficulty in determining parameters for the improvement of cutting performance and optimization, analysis of variance and regression analysis were made use of. Tungsten carbide cobalt metal matrix composites finds increasing applications in conventional application like tools and dies as well as in developing fields like bio-medical instruments and aero-space industries. In this present work, the problem of parameter selection, optimization for wire electro discharge machining on tungsten carbide-15% cobalt metal matrix composites, a less worked composition has been undertaken. Sodick AQ-427L wire-edm machine was used with a 0.25 diameter zinc coated brass wire electrode, to cut the material. Each experiment done under different cutting conditions of inputs like pulse on time, pulse off time, wire speed and peak current and repeated for three observations and the average was selected. Optimum machining parameter combination for material removal rate was obtained by using the desirability response optimizer function. Analysis of variance, Confirmation experiment was carried and good improvements were obtained.