MACHINING OF WC-Co COMPOSITES

Abstract

Operating conditions for maximum removal rate were established using a wire electrical discharge machine (EDM) with pulse type power supply. Material removal was primarily by vaporization and melting of cobalt followed by the dislodging of WC grains. The resolidified liquid smears the surface cracks and decreases the surface roughness. In spite of the anisotropic residual stresses created, the hardness changes are insignificant. In view of results obtained using a diamond saw, it is obvious that EDM-ing produces roughness and hardness comparable to a low speed diamond saw but with higher removal rates.