Cailiao Baohu (Jan 2022)

Study on Surface Passivation Process and Corrosion Resistance of Passive Film on 5052 Aluminum Alloy

  • CHEN Er - jun, DANG Lu - wei

DOI
https://doi.org/10.16577/j.issn.1001-1560.2022.0018
Journal volume & issue
Vol. 55, no. 1
pp. 142 – 146

Abstract

Read online

In order to improve the surface corrosion resistance of automotive aluminum alloy components, the chemical passivation of chromium sulfate was selected to study the surface passivation process and corrosion resistance of passive film of 5052 aluminum alloy. The influences of the Cr2(SO4)3 concentration, K2ZrF6 active agent concentration in passivation solution, and the passivation time on the passivation quality were investigated. In addition, the corrosion resistance of passive film was studied by neutral salt spray test and cupric sulfate dropping corrosion test. Results showed when the conditions were 1.0 g/L Cr2(SO4)3, 2.5 g/L K2ZrF6, and 3 min of the passivation time, the obtained passivation film was continuous, uniform, and had good gloss. The passive film met the requirements of 240 h salt spray test and had the best corrosion resistance, which could meet the anti - corrosion requirements of automotive aluminum alloy appearance parts.

Keywords