Characterization of Ti-31 Alloy Coated with WC–Co/Cr by HVOF Technique

Aerospace, power generation, oil and gas, and manufacturing industries are key economic sectors of any nation. These sectors require protective coatings for functioning of critical parts that are subjected to abrasion, corrosion and, erosion prevailing at elevated temperature. High-velocity oxy-fuel coatings (HVOF) and plasma spray coatings are widely used as coating techniques to coat the metal and alloy substrate with high-temperature ceramic coatings to withstand the severe stresses and wear of the critical parts and enhance its life thereby, saving downtime and repairs. In this paper, an attempt has been made to give HVOF coating of 80%WC–15%CO–5%Cr on Ti-31 alloy substrate for gas turbine blades. Visual evaluation, microstructure evaluation, coating thickness, and microhardness are evaluated as per ASTM standards. Coatings are dense and have a typical lamellar structure and are deposited successfully by using HVOF spray coating technology and obtained microhardness of 526 HV on 423-micron coating thickness on Ti-31 substrate.