摘要


TiC1 − xNx-based cermets are attractive for high-speed cutting operations, and are usually produced by powder sintering at high temperatures and for a long time. In this paper, dense TiC1 − xNx–Ni3Ti cermet is directly prepared in one step by combustion synthesis in 2 MPa N2 atmosphere, from the reactant of (Ti + C + Ni) with a molar ratio of Ti:C:Ni = 1:0.7:0.4. The as-prepared TiC1 − xNx–Ni3Ti cermet shows a homogeneous microstructure, in which equiaxed TiC1 − xNx grains of a few microns are bounded by Ni3Ti grain-boundary phase, and a Vickers hardness of 12.1 ± 0.3 GPa. It is proposed that the deficiency of C in the starting reactant plays a key role in simultaneous densification during combustion synthesis. Compared with the conventional powder sintering approach, combustion synthesis may provide a one-step, ultrafast, and furnace-free way to prepare TiC1 − xNx-based cermets with reduced time and energy consumption.

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