Optimization of Multi Response Parameters in WEDM of Al 6351 based Hybrid Metal Matrix Composite using Grey Relational Analysis

Abstract

The main thrust of the paper is to optimize process parameters in Wire Electrical Discharge Machining (WEDM) of a hybrid MMC of Al alloy (Al 6351) reinforced with 6% Graphite (Gr) and 4 % Silicon carbide (SiC) particles, for multiple responses by grey relational analysis (GRA). Experiments are designed by L27 orthogonal array and conducted by changing  the WEDM  process  parameters  like pulse on time(PON), pulse off time(POFF), wire feed(WF), spark voltage(SV) and wire tension(WT), which are optimized with the considerations of multiple responses namely surface texture/ surface roughness or simply roughness (SR), metal removal rate(MRR), dimensional deviation(DD) and kerf width(K). The optimum values of process parameters are identified by using the grey relational grade attained  from GRA and Fisher Analysis of variance  is done to identify  the contribution of input parameters. To validate the test result a confirmation test is conducted. It is found from the results that the machining responses can be enhanced efficiently by this technique.