Abstract
The steel-cutting type is changing from wet process type to semi-dry or dry process type, and the cutting speed is turning to higher range in recent years. The cemented carbides for such cutting tools needs high creep resistance as well as high wear resistance and high fracture toughness. In this study, the effect of WC grain size distribution on the steady state creep rate was investigated on WC-Cr3C2-Co cemented carbides for getting a guiding principle of the improvement of the creep resistance. It was found that the steady state creep rate at a fixed mean grain size became considerably smaller together with the increase of creep rupture time by widening the grain size distribution. The results were considered from the viewpoint of the climbing motion of dislocations pile-uped in front of WC grains by using three kinds of model alloys.
