医用镍钛合金表面微弧氧化膜层的显微结构及耐蚀性  

Microstructure and corrosion resistance of microarc oxidation coating on surface of biomedical nickel-titanium alloy

作　　者：徐吉林[1] 刘福[2] 罗军明[1] 

机构地区：[1]南昌航空大学材料科学与工程学院,江西南昌330063 [2]哈尔滨工业大学材料学院,黑龙江哈尔滨150001

出　　处：《电镀与涂饰》2011年第12期41-44,共4页Electroplating & Finishing

基　　金：国家自然科学基金(51101085)

摘　　要：采用由NaAlO2和NaH2PO2组成的电解液,以微弧氧化技术在医用镍钛合金表面制备Al2O3陶瓷膜层,以减少合金表面Ni含量,并进一步提高其耐腐蚀性能,使其具有良好的生物相容性。随微弧氧化过程中处理时间的延长,试样表面的游动火花由白色逐渐向橙色转变,火花数减少但尺寸增大。所得陶瓷膜层由γ-Al2O3晶相组成,随着处理时间的延长,γ-Al2O3的结晶度增加,膜层表面粗糙度增大,表面微孔数逐渐减少而孔径增大。经60min微弧氧化处理后,镍钛合金在Hank’s溶液中的自腐蚀电位比基体高142mV,自腐蚀电流密度降低了近2个数量级,耐蚀性有了大幅提高。An NaAlO2 ceramic coating was prepared on the surface of biomedical titanium-nickel alloy by microarc oxidation in a NaAIO2-NaH2PO2 electrolyte. As the treatment time extends during microarc oxidation, the color of the moving spark on the sample surface changes from white to orange, and the number of spark decreases while its size increases. The obtained ceramic coating is composed of γ-NaAlO2 crystal. As the treatment time extends, the crystallinity of γ-NaAlO2 increases, the ceramic coating surface become rougher, and the micropore distributed on the surface of ceramic coating becomes less in number but larger in size. The corrosion potential of nickel-titanium alloy is increased by 142 mV and the corrosion current density of it in Hank＇s solution decreased by 2 orders of magnitude after microarc oxidation for 60 min, indicating that the corrosion resistance of nickel-titanium alloy is improved markedly.

关 键 词：医用镍钛合金 微弧氧化 氧化铝膜层 耐蚀性 

分 类 号：TG174.453[金属学及工艺—金属表面处理]