中文摘要：

利用电化学测试技术和浸泡试验研究了几种电压下的阳极氧化工艺对镁合金在Hank’s仿生溶液中降解性能的影响,同时对Hank’s溶液浸泡前后的氧化膜的形貌和成分进行了比较分析,以探讨氧化膜在仿生溶液中的降解行为。研究表明,随阳极氧化电压增大,阳极氧化膜表面的孔隙增大,电压升至110V时,试样表面烧蚀,阳极氧化膜疏松,平整度较差。阳极氧化提高了镁合金的耐蚀性,100V下的阳极氧化试样具有最大的涂层电阻,90V下阳极氧化试样具有最大电荷转移电阻和极化电阻。阳极氧化处理后的试样在Hank’s仿生溶液中可延缓镁合金降解1周左右,随后析氢速率有所增高。其中110V电压下生成的阳极氧化试样自腐蚀电位降低,浸泡1周后的析氢量明显高于其它试样。浸泡过程中,随着阳极氧化层的溶解,Hank’s溶液中的磷酸根和钙离子沉积在氧化层表面形成磷酸钙盐,其产物进入氧化膜的小孔内,形成无孔表面。

英文摘要：

The degradable performances of magnesium alloy in Hank’s solution after anodization treatment at different voltage were measured by electrochemical measurement technology and immersion test.The morpholo-gies and chemical component of the anode oxide film before and after immersion in Hank’s solution were ana-lyzed by SEM and EDS to discuss the degradation behavior in simulated body fluid.The results indicate that the average size of the pores on the oxide films were increased with the applied voltage,the film ablated with loosen and uneven surface when the voltage reached to 110 V.Anodize oxidation treatment increased the corrosion re-sistance of Mg substrate significantly.Sample at 100 V anodization treatment exhibited largest coating resist-ance （Rf）and 90 V anodized sample has the highest charge transfer resistance （Rt）and polarization resistances （Rp ）.The anodized samples could postpone the degradation of magnesium alloy substrate about one week’s in Hank’s solution,whereafter the hydrogen evolution rates somewhat increased.The corrosion potential （Ecorr） of the 110V anodized sample was more negative than the Mg substrate and the hydrogen evolution rates was higher than that of other coated samples after one week’s immersion.During the immersion,calcium phosphate was formed with the slow dissolution of anode oxide layer due to the Ca^2＋,HPO4^2- and PO4^3- deposition on the coated surface.The reaction products entered the pores of the coating and formed the non-porous surfaces.