L12 strengthening of WC-CoNiFe cemented carbides by spark plasma sintering

Binder phase has very significant effect on the growth of WC grains, grain morphology, the microstructure and properties of cemented carbide. In this paper, Co, Fe and Ni were used as binder phase, cemented carbides with different sintering temperatures were prepared by spark plasma sintering. The differences in the microstructure and properties of 10Co and 8Co-3NiFe were analyzed. The results showed that the 8Co-3NiFe cemented carbide generated the highly ordered FeNi 3 phase with FCC of L1 2 . The addition of Fe and Ni decreases the melting point of 8Co-3NiFe, makes the grain morphology of WC more rounded and more homogeneous distribution of the cemented carbide microstructure. The WC grain sizes of the 10Co and 8Co-3NiFe cemented carbides are very similar, but the 8Co-3NiFe cemented carbide shows a slight increase in grain size. Low-temperature densification of the 8Co-3NiFe cemented carbide can be achieved at sintering temperature of 1050°C. The fracture toughness of the 8Co-3NiFe cemented carbide improves by about 10% compared to the 10Co cemented carbide.