A Study of Wire Electrical Discharge Machining of Carbon Fibre Reinforced Plastic

Abstract

The need for nonconventional machining of carbon fibre reinforced plastics (CFRPs) has emerged due to several problems encountered during their conventional machining. Wire electrical discharge machining (WEDM) is a potential nonconventional machining process having the ability to produce delamination and damage-free features in CFRP laminate. But machining of CFRPs by means of WEDM is a challenging task due to their low electrical conductivity characteristic. The present work focuses on the feasibility study of machining of CFRP laminate by WEDM process. Sandwich assisting electrode method was applied to improve the machining performance of the chosen material. The influence of three input factors, namely, (i) pulse on time, (ii) pulse off time, and (iii) current on machining time has been investigated. The experiments were performed according to full factorial design by taking three levels of each input factor. It was found from the experimental results that the machining time increases marginally with an increase in the pulse on time at a lower level of current (current level of 2). However, the machining time is almost constant for a higher level of current (current level of 4 and 6). The results also showed that the machining time increases with pulse off time and decreases with the current.