低活化结构材料中氢氦与缺陷协同作用的模拟研究

项目名称： 低活化结构材料中氢氦与缺陷协同作用的模拟研究

项目编号： No.11305022

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 张朋波

作者单位： 大连海事大学

项目金额： 26万元

中文摘要： 中子辐照损伤效应是核材料和核技术研发长期面临的主要问题。在中子辐照下，聚变堆结构材料内部产生各种缺陷和核嬗变生成大量的氢、氦杂质，引起微结构变化和气泡形成，导致材料肿胀和脆化，严重影响反应堆的运行寿命。因此，阐明中子辐照下材料中嬗变氢、氦与结构缺陷（空位，空洞，晶界）之间的相互作用，是理解中子辐照损伤机理的关键之一。本项目采用多尺度模拟对低活化结构材料钒合金（V-4Cr-4Ti）和钒固体中氢、氦杂质与空洞和晶界相互作用的微观机制进行深入的理论研究。第一性原理计算研究材料中氢、氦杂质在空洞、晶界处的滞留、迁移、偏聚行为，Cr和Ti合金元素的影响，以及它们的协同作用；分子动力学和蒙特卡罗模拟研究氢、氦杂质与缺陷复合团簇的演化行为；初步建立钒材料中氢、氦杂质与结构缺陷作用的微观物理图像。此研究，为研发抗辐照金属结构材料提供基本数据，具有重要科学意义。

中文关键词： 辐照损伤；氢氦效应；缺陷；结构材料；第一性原理计算

英文摘要： Neutron radiation damage effects are the main problem for developing nuclear material and nuclear technology. Under neutron irradiation, large amounts of defects, H and He impurities from transmutation reactions are generated inside structural materials of fusion reactor, causing microstructural changes and bubble formation, leading to material swelling and embrittlement, and seriously affect operation lifetime of the reactor. Therefore, clarifying the interaction between H and He with structural defects (vacancies, voids, grain boundaries) under neutron irradiation is one of the importance to understand the mechanism of neutron irradiation damage. Using multiscale simulations, this project is to study the microscopic mechanism of interaction between H/He impurities and voids/grain boundaries in the low activation structural material of vanadium alloy (V-4Cr-4Ti) and vanadium solid. First-principles study of retention, migration, segregation behavior of H and He impurities in small void and grain boundary, the effect of the alloying elements Cr and Ti, and their synergetic interactions. Molecular dynamics and Monte Carlo simulations of evolution behaviors of the complex clusters of H-defects and He-defects; a microscopic physical image of interactions between H/He impurities and structural defects in vanadium ma

英文关键词： irridiation damage；;hydrogen/helium effects；defects；structural materials；first-principles calculations