硅溶胶封孔对AZ31镁合金阳极氧化膜抗腐蚀性能的影响（英文）

Effect of SiO_2 Sol Sealing on Corrosion Resistance of Anodic Films of AZ31 Mg Alloy

采用硅溶胶对AZ31镁合金阳极氧化膜进行封孔处理。分别讨论了浸渍时间、焙烧温度及浸渍焙烧次数对氧化膜形貌及抗腐蚀性能的影响。使用扫描电子显微镜(SEM)分析复合膜的表面形貌,利用动电位极化曲线表征膜的腐蚀性能。采用能谱(EDS)和X射线光电子能谱表征封孔后膜的表面组成。结果表明,硅溶胶封孔可提高阳极氧化膜的抗腐蚀性能;浸渍时间为1.5 min,焙烧温度为350℃时,膜的耐腐蚀性能最佳;浸渍-焙烧次数对膜的性能影响也较大,浸渍-焙烧7次时,膜的耐腐蚀性能较好。封孔后,硅溶胶吸附于阳极氧化膜的孔外与孔内。

Silica sol was used to seal the pores of anodic oxide film of AZ31 magnesium alloy. The effect of the immersion time, the calcinating temperature and the immersion times on morphology and corrosion resistance of the film was discussed. Scanning electron microscope（SEM） was employed to characterize the surface morphology of the composite film, and potentiodynamic polarization curves were used to analyze the corrosion behaviors. The surface composition of the sealed anodic films was studied by energy dispersion spectroscopy（EDS） and X-ray photoelectron spectroscopy（XPS）. It has been found that the corrosion resistance of anodic film is improved by sealing by silica sol. When the dipping time is 1.5 min and the calcination temperature is 350 °C, the corrosion resistance of the film is the best. Times of dipping and calcination have a greater influence on the performance of the film. When the dipping-calcination is 7 times, the film has a good corrosion resistance. After sealing, silica sol is adsorbed on inner pores and outside pores of the anodic oxidation film.