Development of NbC-based hardmetals: Influence of secondary carbide addition and metal binder

The current study reports on the influence of the sintering technology and overall chemical composition on the microstructure and mechanical properties of NbC-based hardmetals. The partial replacement of NbC by WC, Mo2C, VC or TiC allows to significantly improve the hardness and toughness of the plain NbC-Co. The influence of different binders, i.e., Co and stainless steel, on the microstructure and mechanical properties of NbC-based hardmetals was investigated. The powder mixtures were sintered in the solid state by pulsed electric current sintering (PECS) and liquid state by conventional vacuum sintering. Detailed microstructural analysis was conducted by electron probe microanalysis (EPMA) mapping and point analysis. Vickers hardness and indentation toughness were assessed.status: publishe