5083铝合金微弧氧化涂层的组织结构与腐蚀性能

Microstructure and corrosion property of micro-arc oxidation coating on 5083 aluminum alloy

针对海洋环境下5083铝合金耐腐蚀性能差的问题,采用微弧氧化法在5083铝合金表面制备陶瓷涂层,利用XRD和SEM分析涂层的组织结构,通过电位极化曲线评价涂层在3.5%NaCl溶液中的腐蚀行为。结果表明:陶瓷涂层由γ-Al_2O_3相组成,氧化时间为3、8和15 min时,对应涂层厚度为8、9和10μm。微弧氧化处理后的5083铝合金的腐蚀电流密度显著降低,耐腐蚀性能提高。

This paper is devoted to addressing the poor corrosion resistance of 5083 aluminum alloy exposed to the marine environment.The solution is achieved by preparing a ceramic coating by micro-arc oxidation on 5083 aluminum alloy;analyzing the phase composition and microstructure of the coatings by XRD and SEM;and evaluating the corrosion behavior of coatings in 3.5％ NaC1 solution by potential polarization curve.The results show that the coatings consisting of γ-A12O3 vary in thickness from 8 to 9 and 10 μm when the oxidation time ranges from 3 to 5 and 8 min.The microarc oxidation surface treatment affords a significant decrease in the corrosion current density of 5083 aluminum alloy,thus improving the corrosion resistance of coated 5083 alloy.