次氯酸钠对Ti6Al4V合金表面阳极氧化膜的形成和性能的影响

摘要

Anodic films were successfully fabricated on Ti6Al4V alloy by anodic oxidation method in an environmental friendly electrolyte with and without sodium hypochlorite. The anodic films were characterized by means of the scanning electron microscope (SEM) and energy dispersive spectrometer (EDS). Results revealed that the addition of sodium hypochlorite leads to the ultrafast growth of oxide films, and results in the significant changes of morphology and thickness. The influence of sodium hypochlorite on formation and crystallization of oxide films as a function of anodizing time was discussed. Meanwhile, potentiodynamic electrochemical tests and dry sliding wear tests were performed to evaluate the corrosion resistance and tribological properties of oxide films. It was found that the oxide film fabricated with the existence of sodium hypochlorite had improved corrosion resistance and tribological properties than the one formed without sodium hypochlorite. Moreover, the effect mechanism of sodium hypochlorite on the growth rate and surface morphologies of oxide films during the anodizing process was discussed. It was found that hypochlorite ions participated in the reaction on anode which causes the rapid growth of oxide films and then affect the whole anodizing process.%在环保型的槽液中有无添加次氯酸钠的情况下都成功制备了Ti6Al4V合金表面的阳极氧化膜.使用扫描电镜、能谱仪对制备的阳极氧化膜进行表征.结果显示,添加次氯酸钠可以引起膜层的快速生长以及膜层形貌厚度的显著变化.研究了随着时间的变化次氯酸钠对膜层的形成和结晶度的影响.同时,采用动电位极化和干摩擦滑动测试来评估阳极氧化膜的耐蚀和耐磨性能.结果发现,在次氯酸钠存在的条件下形成的膜层具有较好的耐蚀和耐磨性能.对次氯酸钠作用于氧化膜的生长速率和表面形貌的影响机制也进行了研究,发现在阳极氧化过程中,次氯酸根离子参与了阳极的反应,因此引起了氧化膜的快速生长进而影响整个阳极氧化过程.