Effect of solution temperature on the microstructure and properties of ceramic coating on the surface of 2024 aluminum alloy

Abstract

This study investigates the influence of the 2024 aluminum alloy was treated with solution before ceramic treatment on the microstructure and characteristics of ceramic coatings applied to 2024 aluminum alloy substrates. The microhardness, corrosion resistance, and microstructural properties of these ceramic coatings were assessed using a microhardness tester, an electrochemical workstation, and a scanning electron microscope. The findings indicate that pre-treatment involving solution treatment significantly enhances the hardness and corrosion resistance of 2024 aluminum alloy ceramic coatings. Notably, when the solution temperature was maintained at 460 °C, the most rapid decrease in current density was observed during the ceramization process, resulting in the attainment of the lowest final stable current density. This particular condition yielded ceramic coatings with optimal hardness and corrosion resistance, with hardness exhibiting a remarkable increase of 48.9 HV, self-corrosion potential rising by 0.207 V, and polarization resistance surging by 5310.7 Ω. Moreover, the surface of the ceramic coating displayed remarkable smoothness and was devoid of discernible defects such as cracks or looseness. In light of these findings, it can be concluded that the optimum solution temperature for achieving these desirable properties is 460 °C. This conclusion is derived from a comprehensive analysis encompassing both the morphology and corrosion resistance of ceramic coatings.