Enhanced wear resistance, corrosion behavior, and thermal management in magnesium alloys with PEO coatings

Abstract

The harsh conditions encountered in aerospace applications, such as high operational temperatures, abrasive wear, and corrosive substances, present significant challenges to the performance and longevity of magnesium alloy components. To create a coating with superior wear resistance, corrosion resistance, and high emissivity, this study employs plasma electrolytic oxidation (PEO) technology to develop a nanocomposite coating doped with carbon nanotubes (CNTs) and hexagonal boron nitride (h-BN). The results demonstrate that the MgO-BN/CNTs coating with an emissivity of 0.82 reduces the equilibrium temperature of the 5 W LED junction by nearly 10 °C compared to the magnesium alloy substrate, showing improved radiative heat dissipation performance. Due to the ability of the porous structure to accommodate abrasive particles, coupled with the lubricating effect of h-BN and CNTs, the friction coefficient of the MgO-BN/CNTs coating is 0.57, which is 21 % lower than that of the MgO coating. Additionally, the coating exhibits excellent corrosion protection, attributed to the dense microstructure and chemical inertness of h-BN. The findings demonstrate that the strategic incorporation of h-BN and CNTs into PEO coatings effectively improves the wear resistance, corrosion resistance, and thermal management performance of magnesium alloys.