Shin Byung-Hyun, Lim Jinsurang, Kim Doo-In, Ok Jung-Woo, Kim Seongjun, Park Jinyong, Hong Jonggi, Lee Taekyu, Yoon Jang-Hee, Lee Je In
Yeongnam Regional Center, Korea Basic Science Institute, Busan 46742, Republic of Korea.
School of Materials Science and Engineering, Pusan National University, Busan 46742, Republic of Korea.
Materials (Basel). 2025 May 15;18(10):2298. doi: 10.3390/ma18102298.
High-entropy alloys (HEAs), such as the Cantor alloy, are considered for various structural applications owing to their excellent corrosion resistance and high strength at low temperatures, typically below -70 °C, including cryogenic conditions. However, during metalworking, introducing stresses and grain refinement can reduce the corrosion resistance of HEAs. Recrystallization heat treatment relieves these stresses and homogenizes the grain structure, thereby restoring their corrosion resistance and physical properties. However, inadequate heat treatment can result in a microstructure in which coarse and refined grains coexist; thus, the corrosion resistance is diminished and the physical properties are compromised. Therefore, a proper heat treatment is essential for achieving the desired corrosion resistance and mechanical properties of HEAs. In this study, a cold-rolled high-entropy Cantor alloy was subjected to heat treatment for various durations, and the conditions were analyzed. The microstructure and electrochemical behavior were examined. The results indicated that the grains coarsened after a heat treatment time of 5 min and the residual stresses decreased for 15 min. The potential increased from -0.20 to -0.09 V, whereas the resistance of the passive layer increased from 39 to 56 kΩ. These findings confirm that in the Cantor alloy, residual stress reduction and recrystallization begin after 5 min of heat treatment at 1100 °C, which contributes to the recovery of corrosion resistance. The corrosion resistance of the Cantor alloy can be effectively controlled through heat treatment. This underscores the importance of optimizing the heat treatment process in the manufacturing of Cantor alloys.
高熵合金（HEAs），如康托合金，因其优异的耐腐蚀性以及在低温（通常低于-70°C，包括低温环境）下的高强度而被考虑用于各种结构应用。然而，在金属加工过程中，引入应力和晶粒细化会降低高熵合金的耐腐蚀性。再结晶热处理可消除这些应力并使晶粒结构均匀化，从而恢复其耐腐蚀性和物理性能。然而，热处理不足会导致粗大晶粒和细化晶粒共存的微观结构；因此，耐腐蚀性会降低，物理性能也会受到损害。所以，适当的热处理对于实现高熵合金所需的耐腐蚀性和机械性能至关重要。在本研究中，对冷轧高熵康托合金进行了不同时长的热处理，并对其条件进行了分析。研究了微观结构和电化学行为。结果表明，热处理5分钟后晶粒粗化，15分钟后残余应力降低。电位从-0.20 V增加到-0.09 V，而钝化层电阻从39 kΩ增加到56 kΩ。这些发现证实，在康托合金中，在1100°C下热处理5分钟后开始出现残余应力降低和再结晶，这有助于耐腐蚀性的恢复。通过热处理可以有效控制康托合金的耐腐蚀性。这突出了在康托合金制造中优化热处理工艺的重要性。
