Empirical modeling and optimization of kerf and wire wear ratio in wire electrical discharge machining

Abstract

Wire electrical discharge machining (WEDM) is a commonly used process in manufacturing industries to machine electrically conductive materials with complex shapes and varying hardness. The performance of any machining process is based on right selection of input variables. The selection of optimal parameters in WEDM is a difficult task as it is a highly stochastic process in nature. The present work deals with the development of empirical relationships for the output responses of kerf (cutting width) and wire wear ratio considering pulse-on time, pulse-off time, wire tension, dielectric flow rate, and wire feed as the input variables. Response surface methodology is used to find the quantitative relations. Subsequently, the developed mathematical models are used for optimization. A recently developed global optimization technique, harmony search algorithm, is applied to find the optimal set of input control variables.