Experiment based parametric investigation and optimization of wire electrical discharge machining process on W-Cu metal matrix composite

Abstract

The process engineers always face technical difficulties while machining of Metal matrix composites (MMCs). Tungsten-Copper (W-Cu) metal matrix composite is one among them. It is a good candidate for thermal and electrical applications and is difficult to machine with conventional machining practices due to its microstructural features. Therefore, it is necessary to investigate machinability aspects of W-Cu MMC. In this paper, the authors attempted to investigate and optimise wire electrical discharge machining (WEDM) process on W-30Cu MMC. The effects of Pulse on Time, Pulse off Time, Peak Current, Wire Tension and Spark Gap Set Voltage were investigated experimentally on Material removal rate (MRR) and Surface roughness (Ra). Experiments were conducted according to central composite design and response surface methodology was employed for investigation of process variables affecting MRR and Ra. Subsequently, the wire electrical discharge machining aspects of W-30Cu MMC were discussed. Furthermore, the WEDM process is optimised in single and multi-objective domains using Desirability Function (DF) approach. The predicted optimal values of MRR and Ra are 1.7509 g/h and 0.50 μm respectively. The confirmatory results had shown a significant improvement in MRR and Ra due to process optimisation. The novelty of this work is to explore the machinability aspects of the WEDM on W-30Cu MMC.

Keywords:

• Desirability
• MMC
• optimisation
• WEDM
• W-Cu