Effect of He/dpa ratio on bubble characteristics in Fe9Cr1.5W0.4Si F/M steel during irradiation and annealing  

作　　者：Dewang Cui Kefei Pei Ziqi Cao Yipeng Li Yifan Ding Yuanming Li Shichao Liu Guang Ran 

机构地区：[1]College of Energy,Xiamen University,Xiamen,361102,China [2]Science and Technology on Reactor System Design Technology Laboratory,Chengdu,610213,China [3]College of Chemistry and Chemical Engineering,Xiamen University,Xiamen,361005,China [4]Fujian Provincial Nuclear Energy Engineering Technology Research Center,Xiamen,361102,China [5]Nuclear Power Institute of China,Chengdu,610213,China

出　　处：《Journal of Materials Science & Technology》2024年第30期17-24,共8页材料科学技术(英文版)

基　　金：supported by the National Natural Science Foun-dation of China(No.U1967211);the National Science Fund for Distinguished Young Scholars of China(No.12225506).

摘　　要：The He production rate(i.e.,He/dpa)in nuclear reactors strongly affects the degradation of material prop-erties.This is an important but not yet fully understood issue.Here,the effect of He/dpa on bubble char-acteristics in Fe9Cr1.5W0.4Si ferrite-martensitic(F/M)steel was in situ studied during 400 keV Fe^(+)and 30 keV He^(+)dual-beam irradiation at 723 K with three ratios of 100,500,and 2500 appm He/dpa and subsequent stepwise annealing using transmission electron microscopy(TEM).He/dpa strongly affected the bubble characteristics.During irradiation,the higher the He/dpa,the smaller the size of irradiated bubbles,but the higher their density.However,He/dpa didn’t affect the final saturation size of irradiated bubbles for all three cases,which was-2.2 nm.During annealing,high He/dpa caused large,immobile,dense polyhedral bubbles with a wider bubble size distribution,while low He/dpa caused small,low-mobility,and relatively low-density spherical bubbles.It was found that the higher the He/dpa ratio,the greater the swelling during irradiation and annealing,and annealing further enhanced the swelling.Moreover,the tunnel structure was first found in body-centered cubic(BCC)F/M steel during in-situ irra-diation.The current work provides valuable and potential insights for further understanding the He/dpa effects in materials serving in different nuclear reactors.

关 键 词：He effect Ferritic-martensitic steel He bubble Ion irradiation ANNEALING 

分 类 号：TG1[金属学及工艺—金属学]