Disorder-order phase transformations and electrical resistivity of nonstoichiometric titanium carbide

Hetero-epitaxial growth of TiC films on MgO(001) at 100 °C by DC reactive magnetron sputtering

“…The elemental composition established by AES measurements indicated a C/Ti ratio of about 0.84. In comparison with our previous work [20], where slightly sub-stoichiometric TiC epilayers (C/Ti~0.98) of different thicknesses were deposited in same experimental conditions, but at higher substrate temperature (800°C), the lower carbon content of the films deposited in this work at T S = 100°C is explained by a decreased thermal decomposition of CH 4 and CH x radicals at the film' growing interface [23,24]. The oxygen contamination was found to be less than 3 at.%.…”

“…These remarkable properties exhibited by TiC are related to its high energy of cohesion [2,3]. TiC maintains the face centered cubic (fcc) structure, with metallic and non-metallic sublattices, within an extremely broad homogeneity region, where carbon atoms and the structural vacancies are forming a substitutional solid solution in the nonmetallic sublattice [4].…”

Phase equilibria, phases and compounds in the Ti–C system

“…Under equilibrium congruent evaporation one gets p C = y p M ; hence from Eqns (20) and (21) it follows 14 that…”

“…50 The experimental X-ray diffraction pattern in this interval of angles exhibited a slightly`swollen' slope of the {1/2 1/2 1/2} superstructure reflection of the trigonal phase Ti 2 C. 21 The orthorhombic unit cell of the M 3 C 2 superstructure is shown in Fig. 24.…”

“…The calculated disorder ± order transformation temperatures for the Ti 3 C 2 and Ti 6 C 5 phases did not exceed 950 K. 18,20,22 The structure of the ordered phases of nonstoichiometric carbide TiC y has been studied in detail. 21 Samples of nonstoichiometric titanium carbide TiC y with different carbon content (0. 52 TiC0.58 ± TiC0.63 trigonal R " 3m a= b = c = (a0 6 p )/2 12, 128 calculated; Ttrans < 900 K; the homogeneity region corresponds to 750 K Ti3C2…”