Effects of Wire Manufacturing Processes on Microstructures and Mechanical Properties of TIG Hardfaced Specimens Deposited by CoCrMo-Based Alloy Wires

CoCrMo-based alloy wires manufactured by powder metallurgy and casting processes for wear-resistant coatings of aerospace turbine blades are taken as the research objects in this study, and TIG hardfacing experiments are carried out. Microstructure characteristics of the two wires are systematically compared. Furthermore, microstructure differences among the hardfaced layer, transition zone and base metal are analyzed. High-temperature hardness, tensile strength, and stress rupture resistance, as well as friction and wear properties, are measured. The results indicate that favorable weldability is possessed by both wires, whereas obvious discrepancies are found in the morphology of the Laves phase. Better comprehensive mechanical properties are exhibited by hardfaced specimens deposited with powder metallurgy wire. Slightly superior friction and wear properties are shown by hardfaced specimens from cast wire. The intrinsic relationships among wire manufacturing processes, hardfaced specimen microstructures and mechanical properties are elucidated in this study. Theoretical guidance and experimental support are provided for the structural design and engineering application of CoCrMo-based alloy wires.