On the Effects of Wire Electrode and Ceramic Volume Fraction in Wire Electrical Discharge Machining of Ceramic Particulate Reinforced Aluminium Matrix Composites

In this paper, effect of type of wire electrode material and volume fraction of reinforcement on wire electrical discharge machining performance of A359/SiCp composite has been reported. In this study, a plain brass (CuZn37) wire and a copper wire coated with CuZn50 were used as wire electrodes. The volume fraction of the SiC particulate reinforcement was varied from 10% to 30%. While volume fraction was found to be the most significant parameter affecting the cutting rate, the pulse on-time and the type of electrode material were the next in the order of significance. It is interesting to note that the interaction between on-time and volume fraction as well as the interaction between type of electrode material and pulse on-time also had significant influence on the cutting rate. Further, it was found that the cutting rate was greater in the case of coated wire as compared to the plain brass wire. The improvement in the cutting rate was found to be in greater than 58% for the coated wire. Furthermore, the kerf width was found to be smaller in the case of coated wire compared to the plain brass wire. Nevertheless, the surface roughness was found to increase significantly with the coated wire.