抄録
Mechanical properties, cutting performance, etc., of WC-β(WC/TiC=70/30)-TaC-TiN-Co alloy (cobalt contents, 8-8.5%) sintered in vacuum and nitrogen (PN2=2.7 kPa) were studied as a function of TiN/(TaC+TiN) ratios (named TiN ratios).
The grain size of βt(WC-TiC-TaC-TiN solid solution) decreased with increasing TiN ratios and it naturally more decreased in sintering in N2, without change in the grain size of WC. The transverserupture strength, in particular, of HIP-treated alloy sharply increased with TiN ratios of more than 0.2. It was found that the resistance to oxidation of alloys was markedly improved with increasing TiN ratios.
The results of cutting tests showed that the fracturing and flank wear resistances were scarcely affected by TiN ratios, but the cutting performance of the alloy sintered in vacuum was always superior to that of the alloy sintered in N2.
