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Al383/SiO₂ metal matrix composites (MMC) were designed to increase the wear properties of the Al alloy. However, the soft Al matrix was subject to large plastic deformation under high normal load during lubricated sliding wear tests, causing detachment of the reinforced particles. To further increase the wear resistance of the MMC, in this research, Plasma Electrolytic Oxidation (PEO) process was used to form oxide coatings on the MMC. The hard and wear-resistant oxide coatings protected the metal matrix during the wear tests, reducing the wear rate of MMC. The effect of both oxide coating thickness and volume content of SiO₂ particles on the wear behavior of MMC was investigated. It was found that with a proper combination of the volume content of SiO₂ and coating thickness, the MMC exhibited high wear resistance and low friction coefficient.

Powertrain applications of alloy AJ62 arose from its comparative resistance to high temperature deformation among magnesium alloys. In this research, AJ62 permanent-mould cast in different section thicknesses was subjected to immersion corrosion in commercially-available engine coolant. The objective was to determine corrosion behaviour variation among casting thicknesses. Corrosion product accumulation suggests passive film formation, and unlike in other media, the film exhibits certain stability. Extreme thicknesses were used to generate polarization curves for their respective microstructures in engine coolant. Variation with casting section thickness was observed in the curves. These preliminary results indicate coarsened microstructures reduce corrosion resistance of the permanent mold cast AJ62 alloy.