Abstract
A spark plasma sintering(SPS) was applied to sintering and joining of ceramics, cermet and Ni alloy. Cermet was Ti75C25-20mass%Ni which was synthesized by mechanical alloying(MA) process of elemental powders of Ti, C and Ni. TiC, Ni, NiTi and NiTi2 are synthesized by exothermic reaction in heating from this MA powder. When the mixture of Ni powder and Al powder was used as Ni alloy, the joining at 1073K was able to be done in SPS process. However, Ni powder needs 1273K for the joining. This is because the interface of Ti75C25-20mass%Ni/Ni alloy is joined with the compound of Ti and Al. Although ZrO2 was joined with the cermet at more than 1073K in SPS process, the cracks were observed in the ZrO2 layer.
As the plasma in sintering was not observed in this study, the joining and sintering of ceramics/cermet/Ni alloy in SPS depends on the same principle as a hot pressing.
