Preparation and microstructure evolution of diboride ultrafine powder by sol-gel and microwave carbothermal reduction method

摘要

Titanium diboride ultrafine powder was prepared from sucrose, tetrabutyl titanate and boric acid by the sol-gel and microwave carbothermal reduction method. The influence of reaction temperature, ratio of Ti to C and Ti to B on the synthesis of titanium diboride was studied. The results indicated that the carbothermal temperature, the content of carbon and the amount of H3BO3 show obvious effects on the formation of TiB2. 1,300 °C was the optimum synthesis temperature and pure TiB2 could be prepared. The microstructure of prepared TiB2 was investigated by field emission-scanning electron microscopy (FE-SEM), which results showed that the crystalline size of the prepared titanium diboride at 1,300 °C was about 3-5 μm. The quantities of the crystalline phases of the powders prepared at different temperatures were analyzed by Rietveld refinement method.