摘要
采用高频脉冲电源和阶梯降流的方法,于碱性偏铝酸钠溶液中在AZ91D合金表面制备阳极氧化膜。研究了成膜过程、膜层的结构和形貌,评价了膜层的耐酸性和在3.5%NaC l溶液中的耐腐蚀性能。结果表明:在本试验条件下,AZ91D合金表面可形成内层致密且较厚、外层相对较薄、厚度约100μm的氧化膜;阳极氧化膜的耐酸能力远高于基体;经阳极氧化处理后的合金的自腐蚀电位正移,在腐蚀性介质中极化阻力增大,腐蚀电流密度降低,耐腐蚀性能显著提高。
The anodic film was prepared on AZ91D magnesium alloy in the bath of alkaline meta-aluminate by means of step decreasing current with high frequency pulse power. The formation process, structure and morphology of the anodic film were investigated. The acid-resistance and the corrosion resistance in 3.5% NaCl solution were evaluated. The results show that the anodic film is composed of two layers with the thickness of 100 μm. The inner layer is compact and relatively thick, while the outer layer is a little thin. The acid resistance of the anodic film is superior to the matrix. After anodization treatment, the free corrosion potential of the AZ91D shifts to positive, and in the corrosive media, the corrosion current density decreases, which indicates that the corrosion resistance of the alloy is improved by the anodic treatment.
出处
《表面技术》
EI
CAS
CSCD
2007年第1期8-10,共3页
Surface Technology
关键词
镁合金
阳极氧化
脉冲
腐蚀
Magnesium alloy
Anodization
Pulse
Corrosion
