In the present work, the electronic properties of the passive films formed on equiatomic CoCrFeNi and CoCrFeNiAl high-entropy alloys were investigated in sodium chloride solution. The point defect model (PDM) was employed to study the effect of aluminum addition on the transport of p-type or n-type dopants through the passive films. The crystalline structure of the alloys was determined by X-ray diffraction. CoCrFeNi alloy was comprised of one single face-centered cubic crystalline phase. Aluminum addition promoted the formation of a mixed B2 and BCC structure. X-ray photoelectron spectroscopy (XPS) analysis allowed the examination of the correlation between passive film composition and their electronic properties. The major species in the passive film of the CoCrFeNi alloy were Cr₂O₃ and Cr(OH)₃ while Al₂O₃ and Al(OH)₃ were the predominant species in that of the Al-containing alloy. Electrochemical impedance spectroscopy (EIS) was employed to evaluate the corrosion resistance of the alloys. Aluminum addition promoted the formation of a thicker and more defective passive film. The pitting corrosion susceptibility of the HEAs was dependent on the passive film composition and increased with Al addition. The predominance of n-type defects in the passive film of the CoCrFeNiAl alloy was enhanced upon Al addition. Interaction between passive film composition and the electronic properties of the film played a central role in the corrosion resistance of the high entropy alloys.

在目前的工作中，研究了在氯化钠溶液中等原子性CoCrFeNi和CoCrFeNiAl高熵合金上形成的钝化膜的电子性能。使用点缺陷模型（PDM）来研究铝添加对p型或n型掺杂剂通过钝化膜传输的影响。合金的晶体结构通过X射线衍射确定。CoCrFeNi合金由一个单一的面心立方晶相组成。铝的添加促进了B2和BCC混合结构的形成。X射线光电子能谱（XPS）分析允许检查无源膜成分与其电子性能之间的相关性。CoCrFeNi合金钝化膜中的主要物质是Cr ₂ O _3。Cr（OH）₃和Cr（OH）_3，而Al ₂ O ₃和Al（OH）₃是含Al合金的主要种类。电化学阻抗谱（EIS）用于评估合金的耐腐蚀性。铝的添加促进了更厚，更有缺陷的钝化膜的形成。HEA的点蚀敏感性取决于钝化膜的组成，并且随着Al的添加而增加。添加Al可以增强CoCrFeNiAl合金钝化膜中n型缺陷的优势。被动薄膜成分与薄膜电子特性之间的相互作用在高熵合金的耐蚀性中起着核心作用。