Abstract:TiB2-SiC composite powders were prepared by spray-drying, and the influence of slurry solid content, binder content and SiC content on the particle morphology of the spray-dried powder were investigated. TiB2-SiC flattening splats were collected on the polished graphite substrate by air plasma spraying under different substrate temperature and spray distance. The influence of coating parameters on the splat morphology were investigated. Besides, TiB2-SiC coatings were prepared by air plasma spraying. The results indicate that TiB2-SiC powder with high sphericity, and good fluidity is obtained by spray-drying when the solid content of the slurry is 50wt.%, the binder content is 5wt.%, and the SiC content is 10wt.%. With the increase of the substrate temperature and spray distance, the flat particles gradually decreases to form regular disc-shaped particles. Under the flame of plasma, TiB2-SiC particles melting accelerate and collide with the substrate. The molten particles are flattened, rapidly cooled and solidified. Therefore, the TiB2-SiC particles are continuously stacked and connected as a macroscopic coating.