Evolution process of the synthesis of TiC in the Cu–Ti–C system

The evolution process of TiC formation in the 20 wt.% Cu–Ti–C powder mixtures was studied by using differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The TixCuy compounds (Ti2Cu, TiCu, Ti3Cu4 and TiCu4) formed initially via solid-state diffusion reactions between Cu and Ti particles; and then Ti2Cu and TiCu can form a Cu–Ti eutectic liquids at about 1233 K. The unreacted Ti and C particles dissolved into the Cu–Ti liquids and led to the formation of Cu–Ti–C ternary liquids; subsequently, TiC particulates precipitated out of the saturated liquids. At the same time, also the formation of Ti2Cu occurred at the interface between the Cu–Ti liquids and the unreacted Ti particles. As the temperature increased further, the Ti2Cu melted and more Cu–Ti liquids formed; and then C particles continuously dissolved into the Cu–Ti–C liquids and TiC particulates gradually precipitated out of the saturated liquids.