摘要
金属钨(W)及其合金作为未来聚变堆最具应用前景的面向等离子体结构材料(PFMs),其服役性能直接影响聚变堆长期服役的安全性,辐照诱导W及其合金内微结构演化导致的辐照脆化现象始终是限制其工程应用的关键因素。本文基于分子动力学计算结果,进一步完善了辐照诱导材料微结构演化行为的团簇动力学模型,采用更加完备的物理模型描述材料内辐照缺陷的产生行为,并进一步探讨了W基体内辐照缺陷产生过程对微结构演化行为的影响。模拟结果表明,高能初始离位原子(PKA)诱发级联碰撞直接产生的缺陷团簇是W内位错环、空洞演化中最重要的形核机制;非均匀形核所产生的间隙团簇的扩散行为对位错环的长大行为有重要影响,会导致位错环尺寸分布中出现亚尖峰与台阶状形貌。
Tungsten(W)and its alloys are the most prospective plasma facing materials(PFMs)in future fusion reactors.The service performance of W and its alloys directly affects the safety of fusion reactors in long-term service.Irradiation-induced microstructure evolution of W and its alloys leads to the irradiation embrittlement phenomenon,which is always the key factor limiting its engineering application.In this paper,based on the molecular dynamics calculation results,the cluster dynamics model was improved for modeling the irradiation-induced microstructural evolution behavior of materials.A more complete physical model to describe the generation behavior of radiation defects in materials was adopted,and the influence of the generation process of radiation defects in W matrix on the microstructural evolution behavior was explored.The simulation results show that the defect clusters directly generated by cascade collisions induced by high energy primary displacement atom(PKA)are the most important nucleation mechanism in the evolution of dislocation loops and cavities in W.The diffusion behavior of interstitial clusters caused by heterogeneous nucleation has an important influence on the growth behavior of dislocation loops,resulting in the appearance of sub-spikes and step morphology in the size distribution of dislocation loops.
作者
吴石
刘丽霞
邓辉球
贺新福
王东杰
曹金利
杨文
WU Shi;LIU Lixia;DENG Huiqiu;HE Xinfu;WANG Dongjie;CAO Jinli;YANG Wen(Division of Reactor Engineering Technology Research,China Institute of Atomic Energy,Beijing 102413,China;Hunan University,Changsha 410082,China)
出处
《原子能科学技术》
EI
CAS
CSCD
北大核心
2021年第7期1241-1252,共12页
Atomic Energy Science and Technology
基金
国家磁约束核聚变能发展研究专项(2018YFE0308104)
中核集团领创科研项目(LC192209000420)。
关键词
团簇动力学
钨
辐照损伤
微结构演化
cluster dynamics
tungsten
radiation damage
microstructure evolution
