Nb对钠冷快堆包壳用15-15Ti奥氏体不锈钢组织和拉伸性能的影响  

Effect of Niobium Content on the Microstructure and Tensile Properties of 15Cr-15Ni Titanium-Modified Austenitic Stainless Steel Used as Core Components in Liquid Metal-Cooled Fast Reactors(LMFR)

作　　者：乔羽飞 陈思含 任媛媛 梁田[2] 刘春明 马颖澈[2] 刘奎[2] Qiao Yufei;Chen Sihan;Ren Yuanyuan;Liang Tian;Liu Chunming;Ma Yingche;Liu Kui(School of Materials Science and Engineering,Northeastern University,Shenyang 110819,China;Shi-changxu Innovation Center for Advanced Materials,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China;China Institute of Atomic Energy,Beijing 102413,China)

机构地区：[1]东北大学材料科学与工程学院,辽宁沈阳110819 [2]中国科学院金属研究所师昌绪先进材料创新中心,辽宁沈阳110016 [3]中国原子能科学研究院,北京102413

出　　处：《稀有金属材料与工程》2021年第11期4079-4088,共10页Rare Metal Materials and Engineering

摘　　要：使用OM、SEM和TEM等方法研究了质量分数0%,0.21%,0.46%Nb对固溶态和时效态15Cr-15Ni含Ti奥氏体不锈钢(15-15Ti)中析出相类型、形貌及其分布的影响。结果表明,Nb取代了(Ti,Mo)C相中部分Ti、Mo原子,在0.21%Nb和0.46%Nb合金中形成富Nb的(Nb,Ti)C相,而且Nb含量的增加使固溶态的奥氏体基体组织细化。在850℃时效1000 h后,组织中有Sigma相、MC碳化物析出,Nb的增加促进了Nb、Mo元素在Sigma相中的富集,促使Sigma相更为细小、弥散析出。固溶态和时效态试样的室温、650℃拉伸结果表明,在0%,0.21%,0.46%Nb范围内,Nb含量的增加对固溶态合金室温和高温拉伸性能影响较小,而Nb促进析出的Sigma相对时效态合金的拉伸性能影响较小。This study investigated the precipitated phases and tensile properties of titanium-stabilized 15Cr-15Ni austenitic stainless steel with different niobium contents(0 wt%,0.2 wt%,0.46 wt%).The types,morphology and distribution of precipitated phases after solution treatment and aging treatment were characterized by OM,SEM,and TEM.Results show that Ti and Mo are partly replaced by Nb in(Ti,Mo)C phase to form a Nb-rich(Nb,Ti)C phase in 0.21 wt%Nb and 0.46 wt%Nb alloys.What’s more,the increase of Nb content refines austenite matrix structure after solution treatment.The main phases in the alloy after aging at 850℃for 1000 h are Sigma and MC carbides.The increase of Nb content not only promotes the enrichment of Nb and Mo in Sigma phase,but also makes the phase become finer and more dispersed.The mechanical results of the alloy with Nb in the range of 0 wt%,0.2 wt%,0.46 wt%show that Nb content has little effect on the tensile properties of the alloy at room temperature and 650℃.In aged samples,Sigma phases are promoted by the increasing content of Nb,but these precipitated phases do not show obvious effect on the tensile properties.

关 键 词：钠冷快堆 包壳材料 奥氏体不锈钢 Sigma相 拉伸性能 

分 类 号：TG142.71[一般工业技术—材料科学与工程]