Study on Sintering Densification Process of (Ti,W,Mo,Ta,Nb,Zr)(C,N)-(CO,Ni) cermet

Abstract:

In this paper, the sintering densification process of (Ti,W,Mo,Ta, Nb,Zr)(C,N)-(Co,Ni) based cermet was studied. The effects of sintering process on composition, microstructure and properties were discussed. The results show that during the densification process of (Ti,W,Mo,Ta,Nb,Zr)(C,N)-(Co,Ni) based cermets, the mass loss caused by sintering basically ends at the solid phase sintering stage. When the sintering temperature is above 1340℃, the volume shrinkage and density of the alloy increase sharply due to the appearance of liquid phase. The change of nitrogen content in cermet during the sintering process is consistent with the change of magnetic properties of the alloy, and the nitrogen content has a significant effect on the formation of solid solution. When the sintering temperature is 1490 ℃, the comprehensive mechanical properties of (Ti,W,Mo,Ta,Nb,Zr)(C,N)-(Co,Ni) cermets are the best, and the strength and toughness of the cermets can be further improved by the appropriate control of N₂ partial pressure at sintering temperature.

Key words:Cermet; Sintering temperature; Composition; Microstructure; Strength and toughness