NIRT: Uncovering Deformation Mechanisms of Nanostructured Materials

NIRT：揭示纳米结构材料的变形机制

• 批准号: 0210215
• 负责人: Kevin Hemker
• 金额: $ 123.03万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-08-01 至 2007-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0210215&HistoricalAwards=false
• 关键词: NIRT; Uncovering; Deformation; Mechanisms; Nanostructured

This project is a collaborative inter-disciplinary research to elucidate and model the deformation and fracture mechanisms of nanostructured materials. These studies are important for the reliability of next-generation MEMS, NEMS, magnetic and ultra-hard films, and micro/nano devices, in general, that are closely tied to their mechanical performance. A major objective is to obtain a thorough and solid understanding of operative deformation mechanisms operative in nanoscale materials. The study is specifically designed to probe the mechanical response of materials at nano-scales. Novel designs for in situ TEM observations and microsample tensile and transient experiments will be used to uncover and characterize the dominant deformation and fracture mechanisms in high purity vapor and electro-deposited nanostructured thin films. Multi-scale finite element calculations containing physical models will be developed based on the experimental findings. These models along with adaptive meshing and cohesive elements with atomistic descriptions of grain boundaries in nanocrystalline materials will be used to develop models to predict the collective macroscopic response of a compilation of nanocrystalline grains. The undergraduate and graduate students and post-doctoral fellows engaged in this project would be co- advised. Two parallel teams, each including a post-doc, graduate student and an undergraduate research assistant, will be formed and mentoring skills will be developed at all levels.The overriding intellectual challenge of the proposed study is to develop a science based methodology for measuring, describing and modeling deformation and fracture processes at or near nanometer length scales. The results will have application in MEMS, NEMS and other technologies where magnetic and ultra-hard films are used. This project brings together a synergistic combination of expertise on the synthesis of nanocrystalline materials, the electron microscopy, microsample testing, and adaptive meshing and cohesive element modeling. The importance of teamwork is emphasized and all participants will be educated to work in an inter-disciplinary multi-scale environment at the nano scale.

该项目是一项跨学科的合作研究，旨在阐明和模拟纳米结构材料的变形和断裂机制。这些研究对于下一代MEMS，NEMS，磁性和超硬薄膜以及微/纳米器件的可靠性非常重要，通常与其机械性能密切相关。一个主要的目标是获得一个彻底的和坚实的理解，在纳米材料的操作变形机制。这项研究是专门设计来探测材料在纳米尺度上的机械响应。新的设计，在原位TEM观察和微样品拉伸和瞬态实验将被用来揭示和表征高纯度的蒸汽和电沉积纳米结构薄膜的主要变形和断裂机制。将根据实验结果开发包含物理模型的多尺度有限元计算。 这些模型沿着与自适应网格和凝聚力元素与原子的描述晶粒边界的纳米晶体材料将被用来开发模型，预测集体宏观响应的汇编纳米晶体晶粒。参与本项目的本科生、研究生和博士后将共同提供咨询。两个平行的团队，每个团队包括一名博士后，研究生和一名本科生研究助理，将形成和指导技能将在各个层次上发展。拟议的研究的压倒一切的智力挑战是发展一个基于科学的方法来测量，描述和建模变形和断裂过程在或接近纳米长度尺度。研究结果将应用于MEMS，NEMS和其他使用磁性和超硬薄膜的技术。该项目汇集了纳米晶材料合成、电子显微镜、微样品测试、自适应网格划分和内聚元素建模方面的专业知识的协同组合。强调团队合作的重要性，所有参与者将接受教育，在纳米尺度的跨学科多尺度环境中工作。