In-situ TiC-Al3Ti reinforced Al-Mg composites with Y2O3 addition formed by It laser cladding on AZ91D

In-situ TiC-Al3Ti reinforced Al-Mg composites were formed by laser cladding of (Al + Ti + B4C)/Y2O3 composites on A291D. A series of experiments, including SEM, XRD and EDS, had been carried out to investigate the effect of Y2O3 on microstructure evolution of in-situ generated TiC-Al3Ti phases, which has a positive impact on the comprehensive surface performance of the reinforced Al-Mg composites. The results showed that more precipitates with different morphology were formed in the composites ascribe to the addition of rare earth. The morphology of Al3Ti changes from rod shape to X shape when the content of Y2O3 increases. A large amount of Al3Ti and TiC aggregated in the composite with 2% Y2O3. Based on the experiments, the growth mechanism model of Al3Ti and TiC was proposed. The appropriate addition of Y2O3 can ameliorate the micro-hardness, wear resistance and corrosion resistance of the composites.