Ce_(68)Al_(10)Cu_(20)Nb_2大块非晶表面钝化膜的研究  

Passive Film Formed on Ce_(68)Al_(10)Cu_(20)Nb_2 Bulk Amorphous Alloy

作　　者：王国材 肖小波[1] 陈艳萍[1] 王晨[1] 

机构地区：[1]福州大学材料科学与工程学院,福州350116

出　　处：《材料工程》2016年第5期72-78,共7页Journal of Materials Engineering

基　　金：国家自然科学基金资助项目(51001027);福建省自然科学基金资助项目(2012J01200);福建省教育厅资助项目(JA10049)

摘　　要：采用铜模冷铸法制备了Ce_(68)Al_(10)Cu_(20)Nb_2大块非晶合金,利用动电位极化曲线和电化学阻抗谱技术(EIS)研究了合金在1mol/L NaOH溶液中的腐蚀行为,并用扫描电子显微镜(SEM)对电化学钝化前后试样的表面形貌进行了表征,最后利用X射线光电子能谱(XPS)分析了电化学钝化处理获得的钝化膜的成分。结果表明:Ce_(68)Al_(10)Cu_(20)Nb_2大块非晶合金在1mol/L NaOH溶液中具有明显的自钝化现象,钝化区为-0.25~0.50V,维钝电流密度为10-5~10-6 A/cm^2;通过电化学钝化后获得的钝化膜可分为外部疏松层和内部致密层;外层主要是Ce的氧化物/氢氧化物和Nb的氧化物,内层则由Ce,Cu和Al的氧化物/氢氧化物和Nb的氧化物构成,钝化膜从外到内,随深度增加,氢氧化物含量逐渐减少,氧化物含量逐渐增加。The Ces8 All0Cue0Nb2 bulk amorphous alloy was prepared by injection casting into copper mold. The corrosion behaviors of the alloy in lmol/L NaOH solution were investigated by potentiody- namic polarization curve method and electrochemical impedance spectroscopic （EIS） technique. The surface morphology of passive film was investigated by scanning electron microscopy （SEM）. The composition of passive film was characterized using X-ray photoelectron spectroscopy （XPS）. The re- suits show that the Ce68 All0 Cu20 Nb2 bulk amorphous alloy exhibits a self passivation phenomenon in lmol/L NaOH solution with the passive region from --0.25V to 0.50V and the passive current densi- ty between 10-5-10 6 A/cm2. The passive film obtained through electrochemical passivation consists of a porous outer layer and a dense inner layer. The outer layer is mainly composed of the oxides/hy droxides of Ce and the oxides of Nb,the inner layer is composed of the oxides/hydroxides of Ce, Cu, A1 and the oxides of Nb. The content of hydroxides gradually decreases and the content of oxides gradually increases from the surface to the inside of the passive film.

关 键 词：非晶合金 腐蚀 极化 钝化膜 XPS 

分 类 号：TG174.3[金属学及工艺—金属表面处理]