纳米结构BCC-Al_(0.5)CoCrFeNi_(0.4)高熵合金在氯化钠溶液中的电化学腐蚀行为  

Electrochemical corrosion behavior of nanostructured BCC-Al_(0.5)CoCrFeNi_(0.4) high-entropy alloy in sodium chloride solution

作　　者：张博威 张泽群 董其娟 吴俊升 庄宁[1] 左鹏程 李晓刚 Bo-wei ZHANG;Ze-qun ZHANG;Qi-juan DONG;Jun-sheng WU;Ning ZHUANG;Peng-cheng ZUO;Xiao-gang LI(Institute for Advanced Materials and Technology,University of Science and Technology Beijing,Beijing 100083,China;National Materials Corrosion and Protection Data Center,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]北京科技大学新材料技术研究院,北京100083 [2]北京科技大学国家材料腐蚀与防护科学数据中心,北京100083

出　　处：《Transactions of Nonferrous Metals Society of China》2024年第6期1908-1921,共14页中国有色金属学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (No.51901018);the Young Elite Scientists Sponsorship Program by China Association for Science and Technology (Nos.YESS,2019QNRC001);the Fundamental Research Funds for the Central Universities,China (Nos.FRF-AT-20-07,06500119);the Natural Science Foundation of Beijing Municipality,China (No.2212037);the National Science and Technology Resources Investigation Program of China (No.2019FY101400).

摘　　要：采用电化学测试并结合对合金表面膜的细致表征,研究Al_(0.5)CoCrFeNi_(0.4)高熵合金(HEA)在3.5%NaCl(质量分数)溶液中的电化学腐蚀行为。结果表明,Al_(0.5)CoCrFeNi_(0.4) HEA主要由富含Al、Ni的B2相和富含Cr、Fe的A2相组成。在电化学极化作用下,合金表面均匀地形成了一层富含Cr的超薄钝化膜。随着外加电位的增加,保护膜在两相界面处破裂,随后B2相优先溶解。最后,在HEA表面形成三层结构的表面膜:内层富集Cr、中间层富集Fe,外层富集Al和Ni。内层和中间层的形成可归因于Cr物种的高稳定性和Fe的选择性溶解,而腐蚀产物的沉积形成表面膜外层归因于B2相的溶解。The electrochemical corrosion behavior of Al_(0.5)CoCrFeNi_(0.4) high-entropy alloy(HEA)in 3.5 wt.%NaCl solution was investigated by electrochemical measurements coupled with comprehensive characterization of its surface films.The results demonstrate that the Al_(0.5)CoCrFeNi_(0.4) HEA primarily consists of(Al,Ni)-rich B2 phase and(Cr,Fe)-rich A2 phase.When subjected to electrochemical polarization,an ultrathin passive film rich in Cr is homogeneously formed on the surface.As the applied potential increases,the protective film tends to break down at the interface of two phases,followed by the preferential dissolution of B2 phase.Finally,the surface film with a triple-layer structure is formed on the HEA surface.Specifically,the inner layer and the middle layer are enriched in Cr and Fe,respectively,due to the high stability of Cr species and the selective dissolution of Fe.The(Al,Ni)-rich corrosion products are found to deposit at the outmost position ascribed to the dissolution of B2 phase.

关 键 词：高熵合金 电化学腐蚀行为 选择性腐蚀 过钝化 三层结构氧化膜 

分 类 号：TG172[金属学及工艺—金属表面处理]