Research on Stress Corrosion Behavior of 316NG Steels in Liquid Lead-Bismuth Eutectic at 560℃
-
摘要: 为准确获得奥氏体不锈钢与液态金属的相容性，支撑其服役性能评价，本研究采用高温液态铅铋慢应变速率拉伸试验装置，开展了316NG不锈钢在3种溶解氧浓度，即低氧浓度（溶解氧浓度<7×10−8%，质量百分比）、中等氧浓度（溶解氧浓度为2×10−6%~2×10−7%）和饱和氧浓度（溶解氧浓度为1.0×10−3%~3×10−4%）下560℃液态铅铋合金（LBE）中的应力腐蚀行为研究。研究结果表明，相比于氩气环境，316NG不锈钢在液态LBE中会发生应力腐蚀现象，且随着溶解氧浓度降低，裂纹深度越深，断裂延伸率越小，应力腐蚀敏感性越明显。在低氧浓度和中等氧浓度下，316NG不锈钢的断裂模式为表面沿晶开裂和基体韧性断裂相结合的混合断裂模式；在饱和氧浓度下，316NG不锈钢的断裂模式基本为韧性断裂。316NG不锈钢发生应力腐蚀效应的主要原因是试样表面和裂纹尖端无法形成连续稳定的氧化膜，无法阻止铅铋侵蚀基体，促进沿晶裂纹生长，导致试样提前断裂失效。
-
关键词:
- 316NG /
- 液态铅铋合金（LBE） /
- 应力腐蚀 /
- 溶解氧浓度
Abstract: To precisely obtain the compatibility between austenitic stainless steel and liquid metal for the service performance evaluation, this study used a high-temperature liquid lead-bismuth eutectic slow strain rate tensile test device to investigate the stress corrosion behavior of 316NG stainless steel in 560℃ Lead-Bismuth eutectic (LBE) under three dissolved oxygen concentrations: low oxygen concentration (<7×10−8%), medium oxygen concentration (2×10−6%~2×10−7%), and saturated oxygen concentration (1.0×10−3%~3×10−4%). The results show that, compared with argon environment, 316NG steel exhibited stress corrosion in the LBE environment. As the dissolved oxygen concentration decreased, the crack depth increased, the fracture elongation decreased, and the stress corrosion effect became more pronounced. At low and medium oxygen concentrations, the fracture mode of 316NG steel was a mixed fracture mode which involves surface intergranular cracking and matrix ductile fracture. However, at saturated oxygen concentration, the fracture mode primarily consisted of matrix ductile fracture. The main cause of stress corrosion of 316NG steel was the inability of the specimen’s surface and crack tip to form a continuous and stable oxide film. This film is essential in preventing LBE from corroding the matrix. The interaction of LBE with the steel promotes the growth of intergranular cracks. Ultimately, it leads to premature failure of the specimen.-
Key words:
- 316NG /
- Lead-Bismuth eutectic /
- Stress corrosion /
- Dissolved oxygen concentration
-
图 4 不同溶解氧浓度的560℃ LBE应力腐蚀试验后316NG不锈钢试样的断口形貌
Figure 4. Fracture Morphology of 316NG Stainless Steel Specimens after Stress Corrosion Testing in LBE at 560℃ with Different Dissolved Oxygen Concentrations
图 5 不同溶解氧浓度的560℃ LBE应力腐蚀试验后316NG不锈钢试样的标距段剖面形貌
Figure 5. Cross-sectional Morphology of the Gauge Section of 316NG Stainless Steel Specimens after Stress Corrosion Testing in LBE at 560℃ with Different Dissolved Oxygen Concentrations
图 6 316NG不锈钢在不同溶解氧浓度560℃ LBE应力腐蚀试验后的二次裂纹深度
Figure 6. Secondary Crack Depth of 316NG Stainless Steels in LBE at 560℃ with Different Dissolved Oxygen Concentrations
图 7 低氧浓度560℃ LBE中316NG不锈钢的裂纹剖面氧化膜成分分析
Figure 7. Composition Analysis of the Oxide Film on the Crack Profile of 316NG Stainless Steel in LBE at 560℃ under Low Oxygen Concentration
图 8 中等氧浓度560℃LBE中316NG不锈钢裂纹剖面氧化膜成分分析
Figure 8. Composition Analysis of the Oxide Film on the Crack Profile of 316NG Stainless Steel in LBE at 560℃ under Medium Oxygen Concentration
图 9 饱和氧浓度560℃LBE中316NG不锈钢裂纹剖面氧化膜成分分析
Figure 9. Composition Analysis of the Oxide Film on the Crack Profile of 316NG Stainless Steel in LBE at 560℃ under Saturated Oxygen Concentration
表 1 316NG不锈钢的化学成分
Table 1. Chemical Composition of 316NG Steel
元素 Ni Cr Mn Si C Mo N Fe 质量百分数/% 11.79 17.34 1.42 0.42 0.025 2.45 0.094 余量 
下载: 导出CSV
表 2 316NG不锈钢的力学性能数据
Table 2. Mechanical Property Data of 316NG Steel
试样编号 屈服强度/MPa 抗拉强度/MPa 断裂延伸率/% I 316NG-氩气 186.20 468.63 58.65 316NG-低氧1 174.31 427.48 44.05 0.34 316NG-低氧2 160.16 424.58 46.65 0.31 316NG-中等氧1 170.23 427.51 47.47 0.29 316NG-中等氧2 174.31 437.72 49.38 0.25 316NG-饱和氧1 170.77 443.56 52.51 0.19 316NG-饱和氧2 171.36 445.44 56.54 0.13
下载: 导出CSV
-
[1] 吴宜灿,FDS团队. 第四代核能系统铅基反应堆前景展望[J]. 科技导报,2015, 33(14): 12. [2] GONG X, SHORT M P, AUGER T, et al. Environmental degradation of structural materials in liquid lead- and lead-bismuth eutectic-cooled reactors[J]. Progress in Materials Science, 2022, 126: 100920. doi: 10.1016/j.pmatsci.2022.100920 [3] SERRE I, VOGT J B. Mechanical properties of a 316L/T91 weld joint tested in lead-bismuth liquid[J]. Materials & Design, 2009, 30(9): 3776-3783. [4] 王军健,李华鑫,李红菊,等. 静态腐蚀条件下铁素体/马氏体钢和奥氏体不锈钢与液态铅铋合金相容性研究进展[J]. 强激光与粒子束,2023, 35(5): 056001. doi: 10.11884/HPLPB202335.220398 [5] 刘静. T91和316L钢在液态Pb-Bi共晶合金中应力腐蚀行为研究[D]. 合肥: 中国科学技术大学,2015. [6] GORSE D, AUGER T, VOGT J B, et al. Influence of liquid lead and lead-bismuth eutectic on tensile, fatigue and creep properties of ferritic/martensitic and austenitic steels for transmutation systems[J]. Journal of Nuclear Materials, 2011, 415(3): 284-292. doi: 10.1016/j.jnucmat.2011.04.047 [7] WANG L, LIAO Q, ZHANG J T, et al. Corrosion behavior of Cr coating on ferritic/martensitic steels in liquid lead-bismuth eutectic at 600 ℃ and 700 ℃[J]. Journal of Materials Research and Technology, 2024, 29: 3958-3966. doi: 10.1016/j.jmrt.2024.02.116 [8] HAMOUCHE-HADJEM Z, AUGER T, GUILLOT I, et al. Susceptibility to LME of 316L and T91 steels by LBE: effect of strain rate[J]. Journal of Nuclear Materials, 2008, 376(3): 317-321. doi: 10.1016/j.jnucmat.2008.02.031 [9] 龚星,肖军,王浩,等. 铁素体/马氏体钢和奥氏体不锈钢的液态铅铋腐蚀行为与机理[J]. 核科学与工程,2020, 40(5): 864-871. doi: 10.3969/j.issn.0258-0918.2020.05.020 [10] 刘金华. 超临界水冷堆条件下310S不锈钢应力腐蚀性能研究[D]. 成都: 四川大学,2019. [11] DAROLIA R, WALSTON W S. Effect of specimen surface preparation on room temperature tensile ductility of an Fe-containing NiAl single crystal alloy[J]. Intermetallics, 1996, 4(7): 505-516. doi: 10.1016/0966-9795(96)00051-9 [12] REHBINDER P A. Investigation of the influence of the surface energy of a crystal on its mechanical properties when the surface tension of its faces is lowered by the introduction of surface-active substances into working medium[C]//Proceedings of the 6th Conference of Russian Physicists, Compendium of Lectures. Moscow: Gosizdat, 1928. [13] MÜLLER G, SCHUMACHER G, ZIMMERMANN F. Investigation on oxygen controlled liquid lead corrosion of surface treated steels[J]. Journal of Nuclear Materials, 2000, 278(1): 85-95. doi: 10.1016/S0022-3115(99)00211-1 [14] ZHANG J, LI N. Oxidation mechanism of steels in liquid-lead alloys[J]. Oxidation of Metals, 2005, 63(5-6): 353-381. doi: 10.1007/s11085-005-4392-3 [15] MARTÍN-MUÑOZ F J, SOLER-CRESPO L, GÓMEZ-BRICEÑO D. Corrosion behaviour of martensitic and austenitic steels in flowing lead-bismuth eutectic[J]. Journal of Nuclear Materials, 2011, 416(1-2): 87-93. doi: 10.1016/j.jnucmat.2011.01.108 -
计量
- 文章访问数: 10
- HTML全文浏览量: 7
- PDF下载量: 1
- 被引次数: 0
