Effect of Titanium Carbide particle addition in the aluminium composite on EDM process parameters

Machining of hard materials such as metal matrix composites (Al/TiC) to a high degree of accuracy and surface finish is difficult. Electrical discharge machining (EDM) is an important process for machining difficult-to-machine materials like metal matrix composites. EDM is an effective tool in shaping such difficult-to-machine materials. The objective of this work is to investigate the effect of current (C)(C), Pulse On-Time (POT) and flushing pressure (P)(P) on Metal Removal Rate (MRR), Tool Wear Rate (TWR) during electrical discharge machining of as-sintered Al-MMC with 5% and 2.5% TiC reinforcement. The use of kerosene as a dielectric fluid was employed in the present investigation. A copper tool of diameter 7 mm was used to drill the specimens. An L18 orthogonal array (OA), for the three machining parameters at three levels each, was opted to conduct the experiments. Analysis of variance (ANOVA) was performed to find the validity of the experimental plan followed in the present work. An attempt was also made in the present work to study the effect of TiC particle addition on the Electrode Wear Ratio (EWR), a new parameter taking into consideration both MRR and TWR. Scanning electron microscope (SEM) analysis was conducted to study the recast layer evolved during the electrical discharge machining process.