Masking in EDM for pattern generation on Al-6061 work surface

Abstract

ABSTRACTElectro discharge machining (EDM) is the most preferred non-traditional method for generating complex-shaped geometric pattern required in industrial and automotive applications. The present study shows the complex-shaped pattern generation by EDM process using polyvinylchloride masking material. Powder metallurgical (PM) green compact tool made of tungsten and copper is utilised to make patterns on aluminium (Al) 6061 workpiece. The effects of contributing parameters i.e. compact load (CL), peak current (Ip) and pulse on-time (Ton) are investigated with respect to performance measures such as surface roughness (Ra) and edge deviation (ED). The selected parameters are optimised using particle swarm optimisation (PSO) technique to determine the optimal levels of CL, Ip and Ton for achieving minimum Ra and minimum ED. The minimum Ra of 5.30 µm and a minimum ED of 43.53 µm are measured at optimal settings of CL of 20 ton, Ip of 2 A, and Ton of 200 µs. Analysis of variance (ANOVA) shows that Ip contributes the most to achieve the lowest Ra, while CL contributes the most to achieve the lowest ED. On the pattern surface FESEM, XRD, and EDS investigations are performed to study the surface morphology and to confirm the transfer of tool particles.