超低温冷冻对304L奥氏体不锈钢的影响分析  

Analysis of the Effect of Ice Plug Isolation by Liquid Nitrogen Method on 304L Austenitic Stainless Steel

作　　者：刘晓东 吴文同 杨云斐 周毅 齐亚宾 乐林紫 LIU Xiaodong;WU Wentong;YANG Yunfei;ZHOU Yi;QI Yabin;LE Linzi(Nuclear Power Operation Management Co.,Ltd.,CNNP,Haiyan,Zhejiang Prov.314303,China)

机构地区：[1]中核核电运行管理有限公司,浙江海盐314303

出　　处：《中国核电》2023年第5期729-733,共5页China Nuclear Power

摘　　要：为了验证核电厂广泛使用的304L奥氏体不锈钢管道材料在低温作用下力学性能是否有明显下降的现象,本文采用理化试验的方法,通过多次超低温冷冻后对304L奥氏体不锈钢管道材料管道进行夏比低温冲击试验、拉伸试验、金相分析、硬度测试、重复冷冻试验,得到对母材、焊缝、熔合线、热影响区的分析,进一步论证了超低温冷冻后金属材料拉伸强度和屈服强度满足材料性能要求,断后伸长率有所降低,说明焊缝的存在对材料的塑性变形能力产生一定影响。在304L奥氏体不锈钢材料遇到低温的场合(如液氮冰塞),本文的结论对相关工作的决策具有借鉴价值。In order to confirm the effect of liquid nitrogen low temperature on the 304L austenitic stainless steel pipe of nuclear power plant,this paper uses the method of physical and chemical testing,through multiple ultra-low temperature freezing after the pipe Charpy low temperature impact test,tensile test,metallographic analysis,hardness testing,repeated freezing test,the analyses for the base material,weld,fusion line,and heat-affected zone are carried out,it is further demonstrated that the tensile strength and yield strength of metal material after ultra-low temperature freezing meet the requirements of material properties,the post-break elongation has been reduced,indicating that the presence of the weld on the plastic deformation capacity of the material has certain impact,the liquid nitrogen method ice plug technique should be focused on in the subsequent operation.This paper provides some reference for the technical operation in the application of liquid nitrogen ice plug freezing isolation technique to the physical and chemical testing of austenitic stainless steel pipe.

关 键 词：液氮 冰塞 304L奥氏体不锈钢 影响 拉伸试验 重复冷冻试验 

分 类 号：TG142[一般工业技术—材料科学与工程]