核电主管道316LN不锈钢的组织和性能  

Microstructure and mechanical properties of 316LN stainless steel for nuclear power main pipeline

作　　者：侍克献 王延峰 张作贵 王苗苗 田根起 SHI Kexian;WANG Yanfeng;ZHANG Zuogui;WANG Miaomiao;TIAN Genqi(Shanghai Power Equipment Research Institute Co.,Ltd.,Shanghai 200240,China;Key Laboratory of Pressure Systems and Safety,Ministry of Education,East China University of Science and Technology,Shanghai 200237,China)

机构地区：[1]上海发电设备成套设计研究院有限责任公司,上海200240 [2]华东理工大学承压系统与安全教育部重点实验室,上海200237

出　　处：《压力容器》2024年第12期1-7,共7页Pressure Vessel Technology

基　　金：国家科技重大专项项目(2015ZX06002004-001)。

摘　　要：为了掌握实心锻造加深孔套料技术制造的CAP1400核电主管道材料316LN不锈钢的性能,对采用该技术生产的两个主管道材料开展显微组织、拉伸性能、冲击性能和低周疲劳性能试验。分析固溶工艺对晶粒尺寸的影响,对不同取向的拉伸性能及其在系列温度下的变化情况进行比较,并评估350℃热老化处理对材料拉伸性能和冲击性能的影响,结合ASME规范对316LN不锈钢的疲劳性能进行评估。结果表明,固溶工艺不同,所生产的316LN主管道材料的晶粒度存在差异;但材料在室温和350℃时的拉伸性能都符合NB/T 20007.33—2015的要求,系列温度下的拉伸性能显示材料的强度差别和晶粒度之间存在相关性;350℃条件下,1000,3000,5000 h实际热老化和模拟20000 h热老化后的显微组织、拉伸性能和冲击性能与原始态接近。采用ASME最佳拟合疲劳曲线和设计疲劳曲线对疲劳性能进行评估的结果表明,两种316LN不锈钢的低周疲劳性能均满足ASME规范的要求。该试验结果可为三代核电主管道的设计、在役检查及寿命评估提供参考。To investigate the performance of 316LN stainless steel for CAP1400 nuclear main pipelines manufactured by solid forging combined with deep-hole trepanning technology,this study conducted comprehensive tests on two pipeline materials,including microstructure analysis,tensile properties,impact toughness,and low-cycle fatigue behavior.The effects of solution treatment on grain size were systematically analyzed.Tensile properties at different orientations and temperatures were compared,revealing a correlation between strength variations and grain size.The influence of thermal aging at 350℃on tensile and impact properties was evaluated.Fatigue performance was further assessed using ASME best-fit fatigue curves and design fatigue curves.Results indicate that the grain size of 316LN steel varies with solution treatment parameters,yet all tensile properties at room temperature and 350℃comply with NB/T 20007.33—2015 requirements.Thermal aging at 350℃(for 1000,3000,5000 h,and simulated 20000 h)caused no significant degradation in microstructure,tensile strength,or impact toughness compared to the as-fabricated state.Both materials meet ASME code requirements for low-cycle fatigue performance.These findings provide critical references for the design,in-service inspection,and lifetime management of third-generation nuclear main pipelines.

关 键 词：316LN钢 主管道 拉伸性能 热老化 低周疲劳 

分 类 号：TH142[一般工业技术—材料科学与工程] TH142.1[机械工程—机械制造及自动化]