Wang Qingmeng, Wang Xiuli, Cheng Xiaomin, Cheng Qianju, Yang Yi
School of Mechatronics and Intelligent Manufacturing, Huanggang Normal University, Huanggang 438000, China.
Hubei Xinghe Electric Power New Materials Co., Ltd., Huanggang 438000, China.
Materials (Basel). 2025 May 7;18(9):2149. doi: 10.3390/ma18092149.
In the fields of nuclear engineering and solar thermal utilization, low melting point alloys with excellent thermal conductivity and heat transfer performance have attracted extensive research as a new generation of heat transfer fluids, leading to many fundamental and important application issues. This study investigates the high-temperature corrosion behavior of Sn-50Bi-2Zn (wt.%) heat transfer alloy against 304 stainless steel (304), 310S heat-resistant steel (310S), and 20 carbon steel (20C) at 600 °C. Theoretical analysis, based on Fick's diffusion law, and experimental measurements reveal significant differences in corrosion severity. After 473 h, 20 carbon steel exhibited the lowest corrosion layer thickness (0.07 mm), while 310S suffered the most severe corrosion (1.50 mm), exceeding 304SS (0.83 mm) by 81%. Diffusion coefficients derived from Sn penetration depths further quantified these trends: D310S = 2.51 × 10 mm/s (6.8 × higher than 304: 3.7 × 10 mm/s) and D20C = 2.87 × 10 mm/s (128 × lower than 304SS). XRF analysis confirmed the dissolution of steel components into the molten alloy, with Fe, Cr, and Ni content increasing to 0.382 wt.%, 0.417 wt.%, and 0.694 wt.%, respectively, after 480 h. These results underscore the critical role of Ni content in accelerating Sn/Zn diffusion and pore formation, providing actionable insights for material selection in high-temperature heat transfer systems.
在核工程和太阳能热利用领域，具有优异导热性和传热性能的低熔点合金作为新一代传热流体已引起广泛研究，引发了许多基础且重要的应用问题。本研究调查了Sn-50Bi-2Zn（重量百分比）传热合金在600℃下对304不锈钢（304）、310S耐热钢（310S）和20碳钢（20C）的高温腐蚀行为。基于菲克扩散定律的理论分析和实验测量揭示了腐蚀严重程度的显著差异。473小时后，20碳钢的腐蚀层厚度最低（0.07毫米），而310S遭受的腐蚀最严重（1.50毫米），比304不锈钢（0.83毫米）高出81%。由Sn渗透深度得出的扩散系数进一步量化了这些趋势：D310S = 2.51×10毫米/秒（比304高6.8倍：3.7×10毫米/秒），D20C = 2.87×10毫米/秒（比304不锈钢低128倍）。X射线荧光光谱分析证实钢成分溶解到熔融合金中，480小时后，Fe、Cr和Ni的含量分别增加到0.382重量%、0.417重量%和0.694重量%。这些结果强调了Ni含量在加速Sn/Zn扩散和孔隙形成中的关键作用，为高温传热系统中的材料选择提供了可行的见解。
