The TiMoCN system: Stability of the (Ti, Mo)(C, N)1−x phase

Abstract The hard constituents in cermet cutting tools are based on titanium carbonitride, mostly with additions of molybdenum and tungsten carbides and usually other carbides such as TaC, NbC, ZrC, VC, etc. In order to gain insight into the typical cermet “core-rim” structure, the TiMoCN system was investigated in the region of the (Ti,Mo)(C,N) 1− x phase. Specific experiments were performed: (Ti,Mo)(C,N) 1− x samples were annealed in nitrogen atmosphere and substoichiometric (Ti,Mo)C 1− x as well as (Ti,W)C 1− x were subjected to nitriding treatments. Although complete equilibrium may not have been reached in any of these experiments, they showed that the phase separation may occur at substoichiometric compositions but probably not at high nitrogen activities.