Experimental investigations on wire electrical discharge machining characteristics of aluminum hybrid composites

Wire electrical discharge machining (WEDM) is a very efficient process for machining composite specimens compared to other conventional machining process. In this work, WEDM process is used to investigate the machining characteristics of aluminum alloy reinforced with hard chromium carbide and soft graphite particles. Optimization of WEDM parameters is carried out to maximize of material removal rate (MRR) as well as to minimize surface roughness (SR) of the composites. Mathematical models were developed using response surface methodology (RSM) to predict the chosen response values. Scanning electron microscope (SEM) investigations showed a near uniform distribution of reinforcements within the matrix. It is found that during WEDM machining process, maximization of MRR of the composite occurred with an increase in pulse-on-time and spark gap voltages. Minimum surface roughness is observed with an increase in peak current and pulse-off time.