学术报告:Computer Simulation of Primary Radiation Damage and Long-term Defect Evolution in Nuclear Materials

2018/06/20 | 【 【打印】【关闭】 | 访问次数:
报告题目: Computer Simulation of Primary Radiation Damage and Long-term Defect Evolution in Nuclear Materials
报 告 人: 李永钢(中国科学院固体物理研究所)
报告时间:2018年6月20日(星期三)上午13:00
报告地点:嘉定园区学术活动中心302会议室

报告简介:
Two major challenges for modeling of radiation damage effects in nuclear materials are how to accurately and effectively describe the interaction of energetic particles with arbitrary complex 3D structures and atomic diffusion events across a wide time-scale (ns - year) at finite temperature. Two new models are thus developed to meet these requirements: a) A universal, open-source and computationally efficient 3D Monte Carlo code, IM3D, has been developed to study ion implantation, sputtering and primary damage in complex nuclear materials. IM3D is based on fast indexing of scattering integrals and the SRIM stopping power database, and allows the user a choice of Constructive Solid Geometry (CSG) or Finite Element Triangular Mesh (FETM) method for constructing 3D shapes and microstructures. b) A spatially resolved cluster dynamics (CD) model, IRadMat, has also been developed for describing the generation, diffusion, reaction and accumulation of defects in materials under ion or neutron irradiation. IRadMat is improved by taking account multi-irradiation fields, ternary defects, multiple degrees of freedom, and multi-scales into the CD model. A sequential multi-scale modeling framework is thus constructed by coupling these two new models with atomistic approaches. Key issues from primary radiation damage to long-term defect evolution in Fe and W are finally studied based on this framework: 1) a concurrent cascade-annealing model for primary defect production and relaxation, 2) the effect of grain size on H/He retention and neutron irradiation damage, and 3) the effect of spatial correlations in cascades on long-term material damage.

报告人简介:
李永钢博士,中国科学院合肥物质科学研究院固体物理研究所副研究员,中科大副教授,硕士生导师。2009年中科大博士,2012-2014年美国麻省理工学院核工系访问学者。中科院青年创新促进会会员,中国材料研究学会计算材料学分会委员。一直专注于高辐照场下材料物性的理论模拟的科学领域,为揭示核材料辐照损伤效应发展了一整套有特色的跨尺度动力学模拟方案,包括空间分辨的任意复杂结构模型以及跨越扩散时间尺度的高效理论计算方法。自主开发了EIMC、IRadMat和IM3D等并行程序,极大地提升了原有初级辐照损伤计算方法对复杂体系的处理能力和效率,在国内率先实现了离子—中子协同辐照下三元一维介观缺陷体系的团簇动力学定量模拟,为探究材料的高热流冲击、高能粒子轰击和辐照损伤长时间演化等关键过程提供了高效的研究手段,并揭示了钨/铍/铁基聚变堆材料的初级损伤的纳米尺寸效应、界面缺陷动力学微观机制、缺陷产生演化和氢氦滞留行为以及长期服役性能。发表IJP、NF、JNM、JAP等SCI论文40余篇;编写一作英文论著章节1篇次;参与制定国际(ISO)和国家(GB)标准各1项;获得中国软件著作权2项;作国际会议大会主题和特邀报告5次。
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