奥氏体不锈钢辐照脆化预测模型建立及验证  

Development and Validation of Radiation Embrittlement Prediction Model of Austenitic Stainless Steel

作　　者：贾丽霞[1] 王东杰[1] 贺新福[1] 吴石[1] 杨文[1] JIA Lixia;WANG Dongjie;HE Xinfu;WU Shi;YANG Wen(China Institute of Atomic Energy,Beijing 102413,China)

机构地区：[1]中国原子能科学研究院,北京102413

出　　处：《原子能科学技术》2024年第8期1635-1645,共11页Atomic Energy Science and Technology

基　　金：稳定基础支持项目(219306)。

摘　　要：奥氏体不锈钢因具有较高的断裂韧性,是反应堆内重要的结构材料。在长期服役过程中,奥氏体不锈钢会遭受中子辐照引起微观结构变化,从而导致断裂韧性下降,影响其服役行为。在反应堆延寿时需考虑奥氏体不锈钢的辐照脆化行为,即断裂韧性降低行为。辐照后断裂韧性实验数据较少,而辐照后拉伸性能实验数据较多,根据断裂韧性与拉伸性能的关系,可以用辐照后拉伸性能数据实现对辐照后断裂韧性的行为预测。为预测奥氏体不锈钢辐照脆化性能,首先根据辐照硬化和辐照后微观结构信息关联模型,利用辐照后微观结构信息实现对辐照后拉伸屈服应力的预测;再根据辐照硬化和断裂韧性的关联模型,利用辐照前的均匀延伸率、屈服应力/流体应力和断裂韧性,结合拟合获得的辐照后流体应力、均匀延伸率,实现奥氏体不锈钢辐照后断裂韧性预测,即实现对奥氏体不锈钢辐照脆化的预测。通过以上步骤,可基于辐照后微观结构信息直接预测奥氏体不锈钢辐照后的断裂韧性。利用文献中获得的奥氏体不锈钢辐照后微观结构实验数据对辐照后断裂韧性进行预测,断裂韧性预测值与文献中报道的奥氏体不锈钢断裂韧性实验值基本吻合,验证了模型的有效性。研究表明,辐照后出现的位错环是引起奥氏体不锈钢辐照脆化的主要微观结构。未来可根据实验测得或模拟计算获得的辐照后微观结构信息,实现对奥氏体不锈钢辐照脆化的预测,为反应堆延寿提供理论指导。Austenitic stainless steels are used as important structural materials in nuclear reactors due to their high fracture toughness.In the process of long-term service,austenitic stainless steel will be subjected to neutron irradiation to cause microstructural changes,such as the formation of dislocation loop and precipitation,which will lead to a decrease in fracture toughness and affect its service behavior.The irradiation embrittlement behavior of austenitic stainless steels,i.e.,the reducing of fracture toughness,should be considered in the life extension of the nuclear reactor.According to the relationship between fracture toughness and tensile properties,the prediction of fracture toughness after irradiation can be realized by using the tensile test data after irradiation.In order to predict the irradiation embrittlement bahavior of austenitic stainless steels,firstly,according to the correlation relationship between irradiation hardening and irradiated microstructure information,the post-irradiation microstructure information was used to predict the tensile yield stress after irradiation.Then,according to the correlation relationship of irradiation hardening and fracture toughness,the uniform elongation,yield stress/flow stress and fracture toughness before irradiation,combined with the yield stress/flow stress and uniform elongation obtained after irradiation,the prediction of fracture toughness of austenitic stainless steel after irradiation was realized,that is,the prediction of irradiation embrittlement of austenitic stainless steel was realized.Through the above steps,the fracture toughness of austenitic stainless steel can be directly predicted based on the microstructure information after irradiation.By using the microstructure information from experimental data obtained in the literature,the predicted fracture toughness was basically consistent with the experimental value of fracture toughness of austenitic stainless steel reported in the literature,which verified the effectiveness of the model.The res

关 键 词：堆内构件 奥氏体不锈钢 断裂韧性 辐照脆化 预测模型 

分 类 号：TL341[核科学技术—核技术及应用]