Effect of Input Parameters of Wire Electric Discharge Machining on Surface Integrity of DC53 Die Steel

Abstract

This paper consists of the effect of input parameters such as pulse on time, current intensity, pulse off time and wire speed of wire electric discharge machining (WEDM) on the DC53 die steel surface roughness and surface integrity. In this study, comparison of the surface machined with optimal level of input parameters for surface roughness and surface with high surface roughness is done. The experiment is performed as per L27 orthogonal array. Analysis of means (ANOM) on the signal to noise (S/N) ratio gives the optimal level of input parameters for achieving low surface roughness. From the analysis of means (ANOM) of the signal to noise (S/N) ratio level of input parameters 4 pulse on time, 9 pulse off time, 2 A current intensity and 9 m/s wire speed will achieve low surface roughness (SR). From the microscopic analysis it is concluded that the surface machined with optimal level of input parameters for surface roughness (SR) not only reduces the surface roughness but also produce good surface integrity. It is observed from the microscopic analysis that relatively finer surface texture is produce with the optimal level of input parameters for surface roughness as compared to the high surface roughness surface. It is also observed that small recast layer is produced on the surface machined with optimal level of input parameters for surface roughness as compared to high surface roughness surface. Moreover, surface having high surface roughness have large number of cracks, large pool of debris, deep craters and large number of spherical deposits as compared to surface machined with optimal level of input parameters for surface roughness.