Wang Junwei, Wen Wenhui, Xie Fa, Wu Bo, Yang Yang, Cheng Jun, Zhang Shilong, Zhang Xianhui
Xiamen Key Laboratory of Marine Corrosion and Smart Protective Materials, Department of Marine Engineering, Jimei University, Xia Men 361021, China.
Fujian Province Key Laboratory of Naval Architecture and Marine Engineering, Department of Marine Engineering, Jimei University, Xia Men 361021, China.
Heliyon. 2024 Jun 19;10(12):e32793. doi: 10.1016/j.heliyon.2024.e32793. eCollection 2024 Jun 30.
In light of the low dissolved oxygen concentration in the deep sea, the corrosion mechanisms of the high entropy alloy (HEA) AlCoCrFeNi in artificial seawater with varying oxygen concentrations (2.0, 4.0, 7.0 mg/L) were studied. As the oxygen concentration decreases, the alloy's free corrosion potential decreases, and at 2.0 mg/L, the corrosion rate is 421 times higher than that at 7.0 mg/L. The corrosion form transforms from pitting to uniform corrosion. The primary reasons for this are the passivation film is thin under low oxygen concentration conditions, as well as the preferential dissolution of the alloy elements Al and Ni due to their high activity and "local acidizing" properties, respectively. In designing a super corrosion-resistant high entropy alloy for use in the deep sea, it is advisable to avoid the use of element Al and to add Ni with caution.
鉴于深海中溶解氧浓度较低，研究了高熵合金（HEA）AlCoCrFeNi在不同氧浓度（2.0、4.0、7.0mg/L）的人工海水中的腐蚀机制。随着氧浓度降低，合金的自腐蚀电位降低，在2.0mg/L时，腐蚀速率比7.0mg/L时高421倍。腐蚀形式从点蚀转变为均匀腐蚀。其主要原因是在低氧浓度条件下钝化膜较薄，以及合金元素Al和Ni分别因其高活性和“局部酸化”特性而优先溶解。在设计用于深海的超耐腐蚀高熵合金时，建议避免使用元素Al并谨慎添加Ni。
