抄録
The conditions for the generation of Co rich layer on the surface of sintered compact of WC-Co submicro-grained hardmetals doped with VC and Cr3C2 were investigated. The following were found: (1) At a normal conditions (1563K-3.6ks, 0.07K/s), there were two kinds, i.e., granular and flat Co rich layers, and these layers were generated at medium sintering temperature, and at any C, VC, Cr3C2 and Co contents, and (2) the granular and flat layer were not generated at higher sintering temperature and at higher cooling rate of sintering, respectively, for all kind alloys. Namely, two kinds of Co rich layers were not generated, when the alloy compacts were sintered at high temperature and then rapidly cooled.
