Mechanochemical In Situ Formation of TiC in a Copper Matrix

The process of mechanochemical synthesis of titanium carbide in the ternary system Ti-C-50 wt.% Cu at a stoichiometric Ti:C ratio was studied using X-ray phase and Xray structural analysis. It is shown that the mechanochemical synthesis proceeds in a mode of mechanically stimulated reaction involving the liquid phases of copper and titanium, as the calculated adiabatic temperature in the ternary system Ti-C-50 wt. % Cu is significantly higher than the melting points of copper and titanium. The induction period of the mechanically stimulated reaction lasts 110 s, followed by a sharp jump in the reaction rate of titanium carbide formation, and within the next 10 s, 85 wt. % TiC with an ordered structure and a composition close to stoichiometric is formed, with crystallite sizes of ~ 47 nm and a low level of microdeformations of ~ 0.24 %. Within the same time frame (120 s), a solid solution of Cu(~ 2 % Ti) with a microdeformation level of ~1 % is formed. Activation for 2–4 min results in the carbon content in titanium carbide and increases the titanium saturation of the solid solution based on copper. An increase in activation time to 16 min leads to the disordering of the titanium carbide structure and carbon depletion, the Cu(Ti) solid solution decomposes, and secondary titanium carbide is formed.