Processing of advanced ceramics using the Wire-Cut EDM process

This paper presents the processing of two advanced ceramics using Wire-Cut Electrical Discharge Machining (EDM) which is evolving as one of the promising method for the processing advanced ceramics. Two types of advanced ceramics, Sialon and Al2O3-TiC, were machined successfully by the Wire-Cut EDM process. The machining performance in terms of material removal rate and surface finish were compared under different cutting conditions. The extent of the surface damage resulting from this thermal machining process were evaluated further by the flexural strength data obtained from three-point and four-point-quarter bend test methods. Moreover, the variability of these flexural strength data were analysed by the Weibull statistical method, which gave a Weibull modulus m ranging from 4.1 to 8.8 for Sialon, and 9.7 to 13.6 for Al2O3-TiC respectively. The results showed that the Wire-Cut EDM process is a viable material processing method for the machining of advanced ceramics, but work have to be carried out to further study the ways and means of improving the surace finish and surface integrity of the machined ceramics such as to give a more reliable service life of components made of advanced ceramics.