Preparation of Ti–Ta–(C,N) by mechanical alloying Ti(C,N) and TaC

Ti(C,N) and TaC powders were mechanically alloyed and FAST/SPS sintered to produce dense (Ti,Ta)(C,N) cermets. Although a pronounced reduction in the crystallite size was observed after 48 hours of mechanical alloying, the bulk of the Ti(C,N) remained unreacted and the formation of solid solution took place only during sintering. The results were compared to cermets prepared under the same conditions from Ti(C,N) and Ta mixtures. These results showed that the use of Ti(C,N) and Ta mixtures is more effective and produces cermets with higher hardness (20.1 HV5) in comparison with the materials produced from Ti(C,N) and TaC powders (12.7 HV5).

► Formation of the (Ti,Ta)(C,N) solid solution phase has been observed.
► Starting with Ti(C,N)-TaC mixture, the phases do not react after 48h milling.
► (Ti, Ta)(C,N) solid solution is better achieved with Ta rather than TaC powder.