Microstructure evolution of T91 steel after heavy ion irradiation at 550 ℃

• 作者: Ligang Song Bo Huang Jianghua Li Xianfeng Ma Yang Li Zehua Fang Min Liu Jishen Jiang Yanying Hu
• 来源期刊: 中国物理B（英文版）
• 年，卷（期）: 2021,（8）
• 所属期刊栏目: SPECIAL TOPIC—Ion beam modification of materials and applications
• 页码范围: 67-76
• 页数: 10页
• 语种: 英文
• DOI: 10.1088/1674-1056/ac0a64

摘要

Fe-Cr ferritic/martensitic (F/M) steels have been proposed as one of the candidate materials for the Generation IV nuclear technologies.In this study,a widely-used ferritic/martensitic steel,T91 steel,was irradiated by 196-MeV Kr+ions at 550 ℃.To reveal the irradiation mechanism,the microstructure evolution of irradiated T91 steel was studied in details by transmission electron microscope (TEM).With increasing dose,the defects gradually changed from black dots to dislocation loops,and further to form dislocation walls near grain boundaries due to the production of a large number of dislocations.When many dislocation loops of primary a0/2〈111〉 type with high migration interacted with other defects or carbon atoms,it led to the production of dislocation segments and other dislocation loops of a0〈100〉 type.Lots of defects accumulated near grain boundaries in the irradiated area,especially in the high-dose area.The grain boundaries of martensite laths acted as important sinks of irradiation defects in T91.Elevated temperature facilitated the migration of defects,leading to the accumulation of defects near the grain boundaries of martensite laths.