Fabrication of TiC from the Cu–Ti–C system under the super-gravity field

Abstract

Abstract An innovative approach of fabricating fine TiC particles through the dissolution of solid carbon in the CuxTi melt and subsequently separation with super-gravity is proposed in this study. The reactant mixtures of titanium sponge, copper and carbon particles reacted at 1573 K for 4 h and then the near-spheroidal TiC grains gradually precipitated out of the Cu–Ti–C system. The influences of copper content, separating temperature, gravity coefficient and separating time on the separation of precipitated TiC from the Cu–Ti–C melt have been studied. The particle size distribution and stoichiometric of TiC were calculated, and the detailed mechanism of fabricating TiC was discussed. The experimental results showed that the mass fraction of copper mixed with TiC in the residue was 6.5 wt% and the yield of the copper-rich phase exceeded 89 wt% under super-gravity treatment with the conditions of χCu = 90 wt%, T = 1523 K, t = 120 s and G = 600. After leaching with the sulfuric acid solution, the purity of TiC particulates was 99 wt% and the removal rate of the copper impurity could be up to 97.8%. Finally, the product of the homogeneous and fine TiC particles with good dispersibility was obtained. The circle equivalent diameter and the median diameter of the TiC particulates were found to be 2.09 μm and 2.12 μm, respectively. The elongation and the aspect ratio of the TiC particulates were 83.4% and 74.4%, respectively. Moreover, the lattice parameter of the purified TiC particulates was calculated by the Nelson-Riley extrapolation function which was near to the standard value, and the stoichiometry of TiC particulates obtained in this work was close to 1.