稀土铈对2A12铝合金微弧氧化膜性能的影响

Effect of Cerium on Properties of Ceramic Coating Prepared by Micro-arc Oxidation on 2A12 Al Alloy

以Na2SiO3和NaOH组成的电解液为基础电解液体系,研究了氧化铈溶胶浓度对微弧氧化涂层试件表面形貌、表面元素含量及相组成的影响。通过对表观硬度的测量及试件在3.5%NaCl溶液中Tafel极化曲线的测量,研究了氧化铈溶胶浓度对涂层表观硬度及耐腐蚀性能的影响。研究结果表明:氧化铈溶胶浓度的增加能够促进Al2O3晶体的形成;添加氧化铈溶胶能够提高微弧氧化涂层的表观硬度,提高其耐蚀性能。

Micro-arc oxidati on process was carried out on 2A12 Al alloy in a dual electrolyte containing Na2 Si O3and Na OH.The effects of Ce O2-sol concentration on the properties of ceramic coating such as morphologies,chemical composition and phase composition were discussed.At the same time,the effects of Ce O2-sol concentration on hardness and corrosion of coating were discussed by measuring the hardness and the electrochemical polarization curves in 3.5% NaCl solution.The results show that it is advantage to form Al2O3 crystal with Ce O2-sol concentration increasing.The addition of Ce O2-sol to the basic electrolyte can enhance the hardness and corrosion resistance of micro-arc oxidation coating.