Modelling, Investigation of Process Responses, Surface Assessment and Parametric Optimization in Powder Mixed Electrical Discharge Diamond Grinding of TI6AL4V Utilizing Grey-Based Taguchi Approach

In this study, the powder mixed electrical discharge diamond grinding (PMEDDG) process was designed and a set-up for machining hard electrically conductive material surfaces built. The paper presents empirical models, investigation, an optimal setting of factors and the distinct surface production in the PMEDDG of Ti6Al4V with aluminium (Al) and silicon carbide (SiC) powder mixed dielectric fluid. The response surface methodology was applied to the modelling. One set of 32 experiments with Al powder and another set of 32 experiments with SiC powder mixed dielectric fluid were performed on a PMEDDG set-up. Current, pulse on time, wheel speed, duty cycle, and volumetric proportion of the powder were taken as input machining variables. Material removal rate and surface roughness were computed as outputs. The behaviour of the input factors against the responses was studied and compared with the SiC and Al powder mixed dielectric fluid used in the PMEDDG process. Further, scanning electron microscopy (SEM) investigations were carried out to determine the impact of different factors on the PMEDDG-produced surfaces as well as the effect of powder presence in the dielectric fluid on white recast layer thickness of the produced surfaces. The grey-based Taguchi approach was used to determine an optimal set of process variables when aluminium powder is used and a confirmation test was conducted on the optimal set to estimate the effectiveness of this approach.