Fabrication of ultrafine TaC powders by mechano-chemical process

Ultrafine TaC powders were synthesized by mechano-chemical process (MCP). The synthesis procedures include (1) preparation of precursor powder by spray drying of liquid solution of tantalum oxalate, (2) calcinations to evaporate volatile components in the precursor powder and synthesis of nanostructured tantalum oxides, (3) ball milling with carbon homogeneously, and then carbothermal reaction in hydrogn. The formation temperature (1050 °C) of TaC in this process is significantly lower than that (1500 °C) in the conventional method. The observed size of TaC composite powders by TEM was smaller than 200 nm.