Abstract
The aim of this investigation is to investigate the contribution of controllable
input parameters (viz. pulse on times, peak currents) on the performance of two newly
developed MMCs (Al-8.5%SiC-1.5%Mo and Al-7%SiC-3%Mo). Both the metal
matrix composites were fabricated using the stir-casting method. Thereafter, various
tests such as microhardness test, tensile test, and porosity analysis of the newly
developed composite were performed. To carry out the machining trials, an L18
orthogonal array (OA) was chosen. Optimization of the machining process was
performed according to Taguchi analysis followed by grey relational analysis (GRA).
The results showed that with increasing weight fraction of the molybdenum
particulates, microhardness and density of the composites increase with a small
reduction in the tensile strength. In addition, pulse on time is the most contributing
parameter among others to obtain optimal process performance. The optimum setting
of input variables suggested by GRA to obtain optimal responses is a molybdenum
composition of 3%, Pulse on time of 70 µs, and a peak current of 9A. Based on the
interaction plot, it is evident that process performance measures of EDM depend on
controllable input parameters.