Dimensional Accuracy Achievable in Wire-Cut Electrical Discharge Machining

Abstract

Wire-cut electrical discharge machining (WEDM) is a popular choice for machining hard and difficult to machine materials with very close tolerances. However, the widely held assumption of the high accuracy of WEDM needs to be investigated, which is the primary aim of this research. This work presents the experimental and analytical results of an investigation into the dimensional accuracy achievable in WEDM. Three techniques—traditional analysis, the Taguchi method, and Pareto ANOVA—are employed to determine the effects of six major controllable machining parameters: the discharge current, pulse duration, pulse gap frequency, wire speed, wire tension, and dielectric flow rate on three key dimensional accuracy characteristics of the prismatic component parts—linear dimensional errors, flatness errors, and perpendicularity errors of corner surfaces. Subsequently, the input parameters are optimized in order to maximize the dimensional accuracy characteristics. The results indicate that the dimensional accuracy that is achievable in WEDM is not as high as anticipated.