Facile synthesis of high-melting point spherical TiC and TiN powders at low temperature

Preparation of high melting point sphere is of great practical value and remains a great challenge. Herein, for the first time a delicate chemical vapor deposition (CVD) process was developed for fabricating spherical TiN and TiC powders, which can hardly be attainable by conventional processes. The big equilibrium constant and released heats are key parameters for obtaining spherical TiN and TiC powders by the CVD process. Sphericity and crystallinity of these spherical powders can be controlled by adjusting nucleation and growth. The optimal TiN spheres (diameter 0.46 mu m, sphericity 0.89) and TiC spheres (diameter 0.52 mu m, sphericity 0.87) were obtained at 850 degrees C under N-2 and H-2 and CH4, respectively. The design ideas explore a novel way to fabricate high melting point spheres.