Wire Electrochemical Discharge Machining of Al₂O₃ Particle Reinforced Aluminum Alloy 6061

Abstract

The behavior of wire electrochemical discharge machining of Al₂O₃ particle-reinforced aluminum alloy 6061 was studied. The effects of machining voltage, current, pulse duration, and electrolyte concentration, on material removal rate (MRR) were evaluated in the light of the contribution of the electrical discharge machining (EDM) and electrochemical machining (ECM) actions. The relative strength of the EDM and ECM activities in the machining process under different conditions was studied with the aid of the voltage waveforms. It was found that the conditions of high current or high concentrations of electrolyte would promote the ECM activity and result in a high MRR. The relative importance of the various cutting parameters on MRR was established using orthogonal analysis. The results suggest that to achieve the highest MRR, the applied current is the most influential factor among current, pulse duration and electrolyte concentration. This outcome is supported by experimental results and is explained in terms of the surface area of the matrix phase and the spark gap size.

Keywords:

• Alumina
• Current density
• Electrochemical discharge machining
• Electrolyte concentration
• Machining gap
• Material removal rate
• Metal matrix composites
• Orthogonal analysis
• Pulse duration
• Voltage waveform

ACKNOWLEDGMENT

This research was fully funded by the Research Committee of the Hong Kong Polytechnic University.