Microstructure Characteristics and Mechanical Properties of Al-12Si Coatings on AZ31 Magnesium Alloy Produced by Cold Spray Technique

The cold spray technique was to deposit Al-12Si coatings on AZ31 magnesium alloy. The influence of gas pressure and gas temperature on the microstructure of coatings was investigated so as to optimize the process parameters. OM, SEM, and XRD were used to characterize the as-sprayed coatings. Mechanical properties including Vickers microhardness and adhesion strength were measured in order to evaluate coating quality. Test results indicate that the Al-12Si coatings possess the same crystal structure with powders, sufficient thickness, low porosity, high hardness, and excellent adhesion strength under optimal cold spray process parameters.