Fabrication Of Plasma-Sprayed Tic-Ti5si3-Ti3sic2 Composite Coatings From The Annealed Ti/Sic Powders

TiC-Ti5Si3-Ti3SiC2 composite coatings were plasma sprayed in-situ using the annealed Ti/SiC powders and raw graphite powder. The microstructure and properties of the sprayed coatings depending on the annealing temperatures of the Ti-SiC powders were investigated. For the annealed Ti-SiC powders, the interface structure of Ti/TiC/Ti5Si3/Ti3SiC2/SiC was formed between Ti and SiC. The sprayed coating from raw powders consisted of TiC, MAX phase Ti3SiC2, Ti5Si3, and residual Si. The sprayed coatings from the annealed Ti-SiC powders consisted of TiC, MAX phase Ti3SiC2, Ti5Si3, and residual SiC. With the increase of the annealing temperature of Ti-SiC powders, TiC and MAX phase Ti3SiC2 increased, and Ti5Si3 phase decreased. For the sprayed coatings from the annealed Ti-SiC powders at 1200 degrees C, their hardness and fracture toughness were enhanced maximally by 33% and 53%, respectively. Their wear resistance was also improved by decreasing the mass loss maximally by 80%.