Multi-attribute optimization of EDM process parameters for machining of SiC and B4C particle reinforced Al 6061 metal matrix composite adopting TOPSIS method

The tendencies of using composite materials are increasing rapidly in advanced engineering and technology applications. Ceramic reinforced aluminum composites are difficult to machine by conventional machining processes. In this work, ceramic reinforced aluminum composites are machined by Electric Discharge Machine (EDM). The goal of this study is to focus on the influence of EDM settings on Al6061 Metal Matrix Composite (MMC) reinforced with Silicon Carbide (SiC) and Boron Carbide (B4C) particles. The MMC is prepared by stirring casting route, then the workpiece is mounted on the electric discharge machine to perform the machining. Because MMC contains high abrasive ceramic (SiC and B4C) particles that are difficult to machine using traditional machining methods, an electrical discharge machine is used for machining. The experiments were conducted with four process parameters like Pulse current (I), Pulse off Time (P-Off), Pulse on Time (P-On), and Tool Lift (TL) with three levels in each parameter to examine the response measures such as Material Removal Rate (MRR), Surface Roughness (SR), Tool Wear Rate (TWR) and Surface Crack Density (SCD). The experimental results reveal that the surface crack density, MRR, SR, and TWR increases with an increase in current and pulse in time. The optimal combinations of process parameters were identified. Obtained optimal machining conditions are I input level at 9 Amps, P-On input level at 20 µs, P-Off input level at 50 µs, and Tool Lift input level at 4.5 µs with results of 0.103g/min MRR, 0.022 g/min TWR, 4.108µm SR and 0.0048 µm SCD.