Electronic Structure Studies on Prismatic Dislocation Loops

棱柱位错环的电子结构研究

• 批准号: 0927478
• 负责人: Vikram Gavini
• 金额: $ 29.5万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2014-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0927478&HistoricalAwards=false
• 关键词: Electronic; Structure; Studies; Prismatic; Dislocation

The embrittlement of metals subjected to radiation is a long-standing problem in various applications including nuclear reactors. The formation of prismatic dislocation loops (dislocation loops whose Burgers vector has a component normal to their plane) is widely believed to be an important factor leading to radiation damage in metals. With the growing interest in nuclear energy, there is a compelling need to understand the properties of these defects and their influence on the structural properties of materials. This project undertakes a fundamental study through quantum mechanically informed calculations to probe into various aspects of prismatic dislocation loops, which include nucleation, growth and migration of these defects, and their influence on the structural properties of materials. In order to conduct these studies, the investigator will develop coarse-graining techniques that enable electronic structure calculations at macroscopic scales. Development of the proposed coarse-graining techniques will bridge the materials science and mechanics viewpoints of materials behavior, which will have a transformative impact in facilitating the design and development of new multi-functional materials. The physical insights provided by this project can guide the design of new materials which provide enhanced performance under radiation exposed extreme thermo-mechanical environments. Moreover, this project will provide education and training for a diverse group of students in a highly interdisciplinary field on the interface of materials physics, applied mathematics, mechanics, and high-performance computing.

在包括核反应堆在内的各种应用中，金属在辐射作用下的脆化是一个长期存在的问题。棱柱位错环的形成（位错环的Burgers向量有一个垂直于其平面的分量）被广泛认为是导致金属辐射损伤的一个重要因素。随着人们对核能的兴趣日益浓厚，迫切需要了解这些缺陷的性质及其对材料结构性质的影响。本项目通过量子力学计算进行基础研究，探讨棱柱位错环的各个方面，包括这些缺陷的成核、生长和迁移，以及它们对材料结构性能的影响。为了进行这些研究，研究者将开发粗粒度技术，使电子结构计算在宏观尺度。提出的粗粒化技术的发展将弥合材料科学和材料行为的力学观点，这将对促进新型多功能材料的设计和开发产生变革性影响。该项目提供的物理见解可以指导新材料的设计，这些新材料可以在极端热机械环境下的辐射下提供增强的性能。此外，该项目将为材料物理、应用数学、力学和高性能计算等高度跨学科领域的不同学生群体提供教育和培训。