Enhanced in-situ reinforcement evolution and superior wear resistance by changing Y2O3 addition in Ti6Al4V-based WC gradient coatings through laser cladding

Abstract

A Y₂O₃-modified wear-resistant coating with a gradient structure of the WC content was produced by laser cladding on a Ti6Al4V matrix. Different Y₂O₃ contents (0 vol%, 1.5 vol%, 3 vol% and 4.5 vol%) were employed to investigate the effect of Y₂O₃ content on the microstructure morphology and tribological properties of Ti6Al4V-base WC gradient coatings. Results indicate that the coating containing 3 vol% Y₂O₃ exhibited the most significant improvement in both microstructure refinement and tribological properties, resulting in 2.58 times increase in wear resistance compared to 0 vol% Y₂O₃ addition and 42.6 times increase compared to the Ti6Al4V matrix. This work provides a preparation method for super wear-resistant coatings and reveals the internal strengthening mechanism of the coatings.