镍钛形状记忆合金表面微弧氧化膜的制备及性能  

Preparation of micro-arc oxidation film on NiTi shape memory alloy and its properties

作　　者：曲凌辉 孟建兵[1] 张宏伟 董小娟[1] 李丽[1] 王帅柯 关庆义 魏修亭[1] QU Linghui;MENG Jianbing;ZHANG Hongwei;DONG Xiaojuan;LI Li;WANG Shuaike;GUAN Qingyi;WEI Xiuting(School of Mechanical Engineering,Shandong University of Technology,Zibo 255000,China)

机构地区：[1]山东理工大学机械工程学院,山东淄博255000

出　　处：《电镀与涂饰》2021年第19期1507-1514,共8页Electroplating & Finishing

基　　金：山东省自然科学基金(ZR2018MEE028);国家自然科学基金(51775321)。

摘　　要：针对镍钛形状记忆合金植入人体时易腐蚀、镍离子过量释放的问题,以NaAlO_(2)、C_(10)H_(14)N_(2)Na_(2)O_(8)、Na_(2)HPO_(4)·12H_(2)O的混合溶液作为电解液对NiTi合金进行微弧氧化。分别以氧化膜的镍元素含量、腐蚀电位和水接触角为评价指标,对氧化电压、氧化电流、脉冲频率和氧化时间这4个因素进行正交试验,综合评价后得到的最佳工艺条件为:氧化电压400 V,氧化电流2 A,脉冲频率200 Hz,氧化时间15 min。借助扫描电子显微镜、能谱仪、接触角测量仪和电化学工作站对微弧氧化前后的NiTi合金表面形貌、化学组成、耐蚀性、亲水性及生物相容性进行了分析和对比。结果表明,微弧氧化后,NiTi合金表面生成了外层多孔、内层致密的陶瓷氧化层,Ni含量减小90%,O和Al含量分别上升至38.97%和25.13%,腐蚀电流密度下降2个数量级,水接触角从63°减小到5°。NiTi合金微弧氧化后的耐蚀、亲水、生物相容等性能得到有效提高,Ni的释放将得到明显抑制。In order to solve the problems of corrosion and excessive release of nickel ions for Ni Ti shape memory alloy being implanted into human body,Ni Ti alloy was treated by micro-arc oxidation (MAO) in an electrolyte containing NaAlO_(2),C_(10)H_(14)N_(2)Na_(2)O_(8),and Na_(2)HPO_(4)·12H_(2)O.The effects of oxidation voltage,oxidation current,pulse frequency,and oxidation time on nickel content,corrosion potential,and water contact angle of MAO film were examined by orthogonal test and the optimal process parameters were obtained as follows:oxidation voltage 400 V,oxidation current 2 A,pulse frequency 200 Hz,and oxidation time 15 min.The surface morphology,chemical composition,corrosion resistance,hydrophilicity,and biocompatibility of Ni Ti alloy characterized by using scanning electronic microscope,energy-dispersive spectrometer,contact angle meter,and electrochemical workstation were compared before and after MAO.The results showed that a ceramic film with a porous outer layer and dense inner layer was formed on the surface of Ni Ti alloy after MAO,where the content of Ni was decreased by 90%,and the contents of O and Al were increased to 38.97%and 25.13%respectively as compared with Ni Ti alloy surface.The corrosion current density was decreased by two orders of magnitude and the water contact angle decreased from 63.9°to 5°for Ni Ti alloy after MAO.The corrosion resistance,hydrophilicity,and biocompatibility of Ni Ti alloy are improved effectively and the release of Ni from Ni Ti alloy would be inhibited obviously by MAO.

关 键 词：镍钛形状记忆合金 微弧氧化 正交试验 耐蚀性 亲水性 镍释放 

分 类 号：TG178[金属学及工艺—金属表面处理]