Investigation of the effect of Process Parameters on Surface Roughness in Wire Electric Discharge Machining of En31 Tool Steel

Modernization of mechanical industry has lead to the increase in demand for hard and tough materials and thus various non traditional methods have been developed in order to machine such hard and tough materials. Wire Electric discharge machine is one of the most commonly used machine which is employed in machining of conductive metals of any hardness or that are difficult or impossible to cut with traditional methods. WEDM is one of the most popular machining methods in present industry which specializes in cutting complex shapes or geometries. The literature survey has revealed that very less work has been done in order to achieve optimal levels of process parameters for Tool Steel-En31 using Brass wire electrode. This paper deals with the study the effect of different process parameters viz. peak current, pulse on time, pulse off time, Wire Tension on the response variableSurface roughness using Brass wire electrode (0.25 mm diameter). Taguchi design methodology has been chosen for design of experiment and L9 orthogonal array has been selected for present study. In this study MINITAB software was used to find the effect of each parameter on response characteristic and to predict the setting of control parameters. ANNOVA and main effect plot have been used to find the significant process parameters and their effect on the response variables. The predicted optimal value of Surface Roughness is further verified by confirmation experiments.