Effect of SiC content on the microstructure and wear behavior of cold-sprayed Al-SiC coatings deposited on AZ31 alloy substrate

Abstract

As a promising and recently developed deposition technique, cold spray deposition method is among the most recently implemented approaches to enhance the poor hardness and wear resistance of AZ31B magnesium alloy. This study investigated the effect of SiC content on the microstructural characteristics, microhardness, and wear behavior of cold-sprayed Al-(16, 28, and 38 wt%) SiC composite coatings. The incorporation of SiC particles into the Al-matrix coating led to the development of a mechanical interlocking mechanism and improved coating-substrate interfacial bonding. The microhardness of the Al-38 wt% SiC coating was approximately 80 % higher than that of the bare substrate due to reduced porosity and a uniform distribution of SiC particles. For coatings with higher SiC content, the dominant wear mechanism transitioned from adhesive to abrasive wear, as evidenced by the friction coefficient (COF) values and wear track micromorphology. The Al-16 wt% SiC coating exhibited the lowest COF and wear rate values, indicating superior wear resistance among the specimens.