SYNTHESIS OF NANOSTRUCTURED TITANIUM CARBIDE FROM TITANIUM OXIDE AND FERRO-TITANIUM THROUGH MECHANICAL ACTIVATION

摘要

Carbides of Ti have been synthesized directly from its oxides and ferroalloys through high energy mechanical milling and heat treatment. Powders of TiO_2 and Fe-Ti mixed with various proportions of graphite were milled in a planetary ball mill for 30 to 90 hours. The milled mixtures were then heat treated at 1100-1300°C for 1 to 2 hours. The as-milled and heat treated powders were characterized by SEM-EDAX, XRD, Pycnometer, and BET techniques. Higher graphite content in the mixture apparently impeded the impact action during milling. Even though longer milling time ensured diminishing particle size, as revealed in SEM, agglomeration was noticed. Formation of carbides of Ti was detected by XRD even in as-milled powders milled for various lengths of time with reduced graphite content along with the change in phase from anatase to rutile. Nanostructured titanium carbide was successfully synthesized under suitable processing conditions using various raw materials. Density, specific surface area and average particle size of the as-milled and heat treated mixtures were correlated with milling time and heat treatment temperature.