耐Pb-Bi腐蚀Si增强型铁素体/马氏体钢和奥氏体不锈钢的研究进展  

Research Advance on Liquid Lead-Bismuth Eutectic Corrosion Resistant Si Enhanced Ferritic/Martensitic and Austenitic Stainless Steels

作　　者：吴欣强[1] 戎利建[1] 谭季波[1] 陈胜虎[1] 胡小锋[1] 张洋鹏 张兹瑜 WU Xinqiang;RONG Lijian;TAN Jibo;CHEN Shenghu;HU Xiaofeng;ZHANG Yangpeng;ZHANG Ziyu(CAS Key Laboratory of Nuclear Materials and Safety Assessment,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China)

机构地区：[1]中国科学院金属研究所中国科学院核用材料与安全评价重点实验室,沈阳110016

出　　处：《金属学报》2023年第4期502-512,共11页Acta Metallurgica Sinica

基　　金：国家自然科学基金项目No.52271077和51871218;中核集团领创科研项目;中国科学院青年创新促进会项目No.2021189。

摘　　要：结构材料是制约铅冷快堆建设的关键因素之一,原因是其组成元素在液态Pb-Bi共晶(LBE)中会发生不同程度的溶解,影响结构安全。候选结构材料铁素体/马氏体钢T91与不锈钢316在550℃饱和氧LBE环境中发生快速氧化腐蚀;溶解氧浓度降至1.26×10^(-6)%(质量分数)可减轻T91的液态LBE腐蚀,但低于1×10^(-6)%时,T91与316钢发生溶解腐蚀;T91液态LBE脆化敏感性高,导致其在350℃液态LBE中腐蚀疲劳寿命显著降低。与商用的(9%~12%)Cr铁素体/马氏体钢和316型奥氏体不锈钢相比,经微合金化的Si增强型铁素体/马氏体钢(9Cr-Si和12Cr-Si)和奥氏体不锈钢(ASS-Si),具有较好的组织稳定性和综合力学性能,且在液态LBE中形成的富Si氧化物提高了氧化膜的致密性,改善了其耐腐蚀性能,在550℃下静态饱和氧和动态控氧LBE环境中的溶解腐蚀受到抑制,有望满足铅冷快堆的设计需求。Structural materials are one of the major factors that restrict the lead-cooled fast reactor construction due to metallic elements that can dissolve in the liquid lead-bismuth eutectic (LBE),which may affect the structure's safety.T91 steel and 316 stainless steel are the leading structural materials for critical equipment such as fuel cladding,reactor vessels,and reactor core internals.The environmental compatibility of those steels with the liquid LBE needs to be systematically evaluated.However,T91 steel and 316 stainless steel suffer from rapid oxidation corrosion in oxygen-saturated LBE at 550~oC.T91 steel's corrosion resistance in liquid LBE can be improved by decreasing the oxygen concentration (1.26×10~(-6)%,mass fraction),but dissolved corrosion occurred at dissolved oxygen concentration below 1×10~(-6)%for T91 steel and 316 stainless steel.T91 steel is sensitive to liquid metal embrittlement,significantly reducing its corrosion fatigue life in the liquid LBE.Compared to the standard (9%-12%)Cr ferritic/martensitic steel and 316 stainless steel,the microalloyed Si enhanced (9%-12%)Cr ferritic/martensitic steel(9Cr-Si and 12Cr-Si) and 316 stainless steel (ASS-Si) have good microstructural stability and comprehensive mechanical properties.The Si-rich oxide formation in liquid LBE improves the oxide film compactness and corrosion resistance.The dissolution corrosion was inhibited in static oxygen-saturation and oxygen-controlled (10~(-6)%-10~(-7)%) flowing liquid LBE (0.3 m/s) at 550~oC for 9Cr-Si,12Cr-Si,and ASS-Si.These alloys are expected to meet the design requirements for a lead-cooled fast reactor.

关 键 词：铁素体/马氏体钢 奥氏体不锈钢 液态金属腐蚀 液态金属脆化 力学性能 组织稳定性 

分 类 号：TL341[核科学技术—核技术及应用]