PLASTIC DEFORMATION OF TRANSITION METAL CARBIDES.

Abstract

This paper concentrates on plastic flow and the brittle to ductile transition in the monocarbides of the Groups IV and V transition metals and tungsten carbide. The determination of slip planes, models for slip and information on the character of dislocations are reviewed. Finally some current work is described that aims to apply information derived from single crystal WC to explain some aspects of deformation in WC-Co. Measurements of hardness anisotropy, TEM observations of dislocations and direct observation of slip lines at indentations provide much information on local plastic deformation at temperatures below the bulk brittle to ductile transition. At low temperatures slip has been observed on (111) (110) and (100) planes in the less than 110 OVER BAR greater than directions in the Group IV and V transition metal monocarbides. The choice of slip system depends on the carbide, carbon content, and temperature. Above the brittle to ductile transition of about 1000 degree C, (111) is the predominant slip plane, but small amounts of slip can occur on other planes just below the transition.