Effect of ordering on the structure and specific heat of nonstoichiometric titanium carbide

The experimental results on the change in the crystal structure and specific heat of nonstoichiometric titanium carbide TiC_y (0.5<y<0.65) near disorder-order phase transitions are reported. It is established that at temperatures below 1000 K the ordered phases Ti₂C with cubic and trigonal symmetry and an orthorhombic ordered phase Ti₃C₂ form in titanium carbide by a close-to-first-order phase transition mechanism. The temperatures and heats of order-disorder phase transformations are determined. Pis’ma Zh. éksp. Teor. Fiz. 69, No. 9, 631–637 (10 May 1999)