Preparation of TiC powders by carbothermal reduction method in vacuum

Abstract

The preparation of fine TiC powders by carbothermal reduction of TiO 2 in vacuum was investigated by XRD, SEM, XRF and laser particle sizer. Thermodynamic analysis indicates that it is easy to prepare TiC in vacuum and the formation sequence of products are Ti 4O 7 (Magneli phase), Ti 3O 5, Ti 2O 3, TiC x O 1- x and TiC with the increase of reaction temperature. Experimental results demonstrate that TiC powders with single phase are obtained with molar ratio of TiO 2 to C ranging from 1:3.2 to 1:6 at 1 550 °C for 4 h when the system pressure is 50 Pa, and TiC 1.0 is gained when the molar ratio of TiO 2 to C is 1:4 and 1:5. In addition, fine TiC 1.0 powders ( D 50 equals 3.04 μm) with single phase and low impurities are obtained when the molar ratio of TiO 2 to C is 1:4. SEM observation shows that uniform shape, low agglomeration, and loose structure are observed on the surface of block product.