A study on machining parameters for Wire Electrical Discharge Machining of Circular Contouring in Stir Cast AA6063/SiC Composites

Abstract

Wire electrical discharge machining (WEDM) is used in machining electric conductive materials for intricate shapes and profiles. This paper presents an experimental investigation on the influence of machining conditions like spark density and voltage cycle time on its performance measures like surface roughness (Ra) and cutting width (Kerf) during machining a circular contour on AA6063/SiC composites. Here, a semi cylindrical piece is removed from a rectangular plate of AA6063/SiC composites plate fabricated with reinforcing SiC in 0%, 5%, 10% and 15% weight fractions through stir casting. The effect of WEDM parameters, spark density is governed by peak current (IP) and sparking rate is governed by voltage cycle time (T) were analyzed for circular contour machining. The experimental results show that increase in SiC content in the composites leads to reduced performance measures. It is observed during the change of spark voltage application time the value of the surface roughness is decreased for the weight fraction of 0% to 5% of SiC and increased for the further inclusion of SiC in the composites.

Keywords

• Metal matrix composites
• Wire electrical discharge machining
• Sparking rate
• Spark density
• Surface roughness