In situ synthesis of TiC/Ti coatings by reactive plasma spraying

Sucrose, as a precursor of carbon, and titanium powders were used to prepare TiC powders by a spray-drying/precursor-pyrolysis method. Using the powders, TiC/Ti composite coatings were deposited by reactive plasma spraying. The results show that submicron-sized TiC is formed. The TiC phases have three kinds of crystal morphology: spherical TiC with a diameter of about 600 nm, dendrite TiC with a primary dendrite spacing of about 450 nm and a secondary arm spacing of about 150 nm, and cellular-dendrite TiC with a width of about 120 nm and a length of about 600 nm. The TiC/Ti coatings exhibit high microhardness and excellent wear resistance, which is about 2–3 times and about 200 times higher than that of TC4 alloys, respectively.