草酸阳极氧化法制备铝合金氧化膜及其防腐蚀性能

为了改进铝合金的防护性能,扩展铝合金应用范围,需要对铝合金进行表面处理。利用草酸电解液阳极氧化法在2A12铝合金表面制备了一层氧化膜,通过扫描电子显微镜(SEM)、X射线光电子能谱(XPS)、X射线衍射仪(XRD)、原子力显微镜(AFM)等手段分析其表面形貌、组织结构、物相和表面粗糙度。微观表征结果表明,阳极氧化法能使铝基体表面生成非晶态的氧化铝薄膜,并且该薄膜是多孔结构,具有优异的屏蔽作用。利用电化学方法、中性盐雾试验评价了阳极氧化膜的防腐蚀性能,证实了阳极氧化后铝合金的防腐蚀性能优于铝合金基体。

Anticorrosion Properties of Aluminum Oxide Films Prepared by Anodic Oxidation in Oxalic Acid Electrolyte

Oxide films were prepared on the surface of aluminum alloy by anodic oxidation method in oxalic acid electrolyte,and the surface morphology,microstructure,phases composition and surface roughness of the films were characterized by scanning electron microscope (SEM),X-ray photoelectron spectroscopy (XPS),X-ray diffractometer (XRD),atomic force microscope (AFM) and other means.Results showed that amorphous aluminum oxide films were formed on the surface of aluminum substrate by anodic oxidation,and the films with vesicular structure possessed excellent shielding capability.Moreover,the electrochemical method and neutral salt spray test were employed to evaluate the corrosion resistance of anodic oxidation films,indicating that the corrosion resistance of aluminum alloy after anodic oxidation was much better than that of aluminum alloy substrate.