抄録
The microstructure and properties of WC-0.9mass%Cr3C2-0.5mass%VC-10mass%Co submicro-grained hardmetal sintered compacts which were prepared by hybrid sintering (a combination method of directly electrifying hot-press sintering with normal sintering, i.e., externally heating pressureless sintering) and normal sintering were investigated. It was found that the lowest sintering temperature for almost full density (≥99% of theoretical density) in hybrid sintering was lower by 30 K than that in normal sintering. The mean grain size of WC in the alloy with almost full density, however, was nearly the same of 0.16 μm for both sinterings. The hardness of the highest value was almost the same of 2170 HV for both sinterings. Thus, it was concluded that hybrid sintering has no merits as far as in grain size and hardness, compared with normal sintering.