فهرست نشریات علمی دسترسی آزاد ایران

The poor tribological behavior of the A356 aluminum-silicon alloy remains a significant drawback that limits its use in automotive components. This study aims to improve the surface properties of the A356 alloy through the plasma electrolytic oxidation (PEO) method and to investigate how the incorporation of silicon carbide (SiC) nanoparticles affects its tribological performance. To this end, oxide coatings were prepared on an A356 substrate by the PEO process in silicate electrolytes containing 0 to 2 g·L⁻¹ SiC nanoparticles. The results revealed that the incorporation of SiC nanoparticles into the PEO process enhanced the coating formation voltage, resulting in increased coating thickness and hardness, while reducing surface porosity and roughness. Evaluation of the wear performance showed that the wear rate of the A356 substrate decreased from 2.64 ± 0.02 × 10⁻⁴ to 1.39 ± 0.02 × 10⁻⁴ mm³·N⁻¹·m⁻¹ with the formation of a pure oxide coating and reached a minimum of 0.17 ± 0.01 × 10⁻⁴ mm³·N⁻¹·m⁻¹ with the incorporation of the maximum concentration of SiC nanoparticles. The evolution of the friction coefficient indicated that the pure oxide coating generated lower friction forces than the A356 substrate, while oxide coatings formed in electrolytes containing up to 1 g·L⁻¹ SiC nanoparticles increased the friction coefficient. Notably, for the oxide coating formed in the electrolyte containing 2 g·L⁻¹ SiC nanoparticles, the friction coefficient decreased to its lowest value. This behavior resulted from the effect of SiC nanoparticles in reducing friction forces by changing the wear mechanism from sliding to rolling.