主成膜剂对2024铝合金微弧氧化膜层特性的影响

Effect of Main Component on the Characteristics of Micro-arc Oxidation Coatings on 2024 Aluminum Alloy

将2024铝合金置于硅酸钠电解液体系下进行微弧氧化处理。用XRD、SEM、膜层测厚仪、硬度计和盐雾腐蚀箱等手段研究了不同的主成膜剂Na2SiO3浓度对2024铝合金微弧氧化膜层物相组成、形貌、厚度、表面硬度和耐蚀性能的影响。结果表明,当Na2SiO3浓度在6g/L~15g/L变化时,随着浓度的增大,MAO膜层的厚度呈现出不断增大的趋势,硬度呈现出先增大后减小的趋势。不同的Na2SiO3浓度下MAO膜层表面均形成了“火山堆”的外貌,随着浓度的增大,“火山堆”数量越来越多,膜层表面越发不平整。综合来看,当Na2SiO3浓度为9g/L时,MAO膜层获得了最佳的综合性能。

The 2024 aluminum alloy is treated by micro arc oxidation in sodium silicate electrolyte system.The effects of the main component of Na2SiO3 concentration on phase composition,morphology,thickness,surface hardness and corrosion resistance of micro arc oxidation coatings on 2024 aluminum alloy were studied by XRD,SEM,film thickness tester,hardness tester,roughness tester and salt spray corrosion chamber.The results show that,when the concentration of Na2SiO3 varies from 6 g/L to 15 g/L,the thickness of MAO coatings increases,and the hardness first increases and then decreases.The surface of MAO coating formed the appearance of"volcanic pile"wih different concentrations of Na2SiO3.With the increase of the concentration,there are more and more"volcanic pile",and the surface of the coating is more and more uneven.In a word,when the concentration of Na2SiO3 is 9 g/L,the MAO coating has the best comprehensive performance.