Influence of the Medium on the Structure And Phase Composition of Ti-C-xNiCr (x=10-40 wt.%) Mixtures from Combustion Synthesis

Self-propagating high-temperature synthesis, a promising synthetic method, was proposed and used to synthesize Ti-C-xNiCr (x = 10 - 40 wt.%) mixtures. The influence of the synthesis medium (argon or vacuum) and the nickel-chromium content in the initial mixture on the phase composition of the synthesized materials, the crystal unit-cell constant of each phase, and the stoichiometry of the synthesized nickel-chromium compound was experimentally studied. The microstructure was studied. The average grain size of titanium carbide was calculated. It was established that the obtained material consisted of two phases, titanium carbide and nickel-chromium, and that the unit-cell constant of both titanium carbide and nichrome decreased with increasing mass fraction of binder from 10 to 30 wt.%. The unit-cell constant increased sharply for the composition Ti-C-40 wt.% NiCr. The effect of the medium during synthesis on the grain size of titanium carbide was studied using the composition Ti-C-30 wt.% NiCr as an example.