EDM Surface Characterization of a Ceramic Composite TiB2/SiC

Abstract

Electrical Discharge Machined (EDM) hole surface characteristics of 20 percent Titanium diboride (TiB2 ) particulate and Silicon carbide (SiC) matrix composite material were investigated. The EDM hole surfaces produced by using brass, copper and graphite were examined by scanning electron microscopy (SEM) and surface profilometry to determine the surface characteristics. As-machined surfaces showed the microcracks in the recast layer, and the individual TiB2 grains were exposed on the surface. The depth of the recast structure on the surface has varied from 8 μm to less than a micrometer and was approximately proportional to the amount of impinging energy or power input. The EDM process appears to be a promising method of producing an excellent surface in electrically conductive TiB2 /SiC composite under slow cutting conditions.