Multiresolution, Coarse-Grained Modeling of 3D Dislocation Nucleation and Migration

3D 位错成核和迁移的多分辨率、粗粒度建模

• 批准号: 0758265
• 负责人: David McDowell
• 金额: $ 40万
• 依托单位: Georgia Tech Research Corporation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-04-15 至 2012-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0758265&HistoricalAwards=false
• 关键词: Multiresolution; Coarse; Grained; Modeling; 3D

CMMI 0758265Multiresolution, Coarse-Grained Modeling of 3D Dislocation Nucleation and MigrationPI: David L. McDowell, Co-PI: Ting ZhuNext generation models to support design of fracture-resistant materials must directly incorporate information related to interatomic bonding and structure of interfaces at nanoscales. The challenge is to develop methods that can address behavior at such small scales yet still account for aspects of average behavior at much higher length scales in structural applications such as automobiles, aircraft, tennis rackets, and so forth. This project will address behavior by linking defects analyzed at the nanoscale using atomistics (molecular dynamics) near the tips of cracks or at interfaces with long range fields that average effects of large numbers of atoms to achieve a so-called ?coarse grain? description. In this way, simulations can be undertaken at high enough length and time scales to provide meaningful information regarding behavior of structures, while the role of interfaces is treated with atomic-scale resolution.This research is expected to substantially impact the ability to tailor the structure of grain boundaries and fine scale microstructure to affect improved fatigue and fracture resistance of metal alloys. Fatigue is a failure mode in metals subjected to cyclic loading that is responsible for costly failures such as highway bridges, airplane tail sections, engine components, railway derailments, and many other examples. By developing more predictive tools to address the large gap in modeling and simulation tools between atomic scales and scales of grains in polycrystals (typically five orders of magnitude), the societal benefits in terms of energy savings and safety derived from more lightweight and durable materials can be substantial. Research results will be integrated into both an undergraduate course in computational materials science as well as graduate courses in defects and mechanical properties of materials taught by the PI and co-PI, accelerating the application of the technology developed in this project.

CMMI 0758265Multiresolution，3D位错成核和迁移的粗粒化建模：David L. McDowell，Co-Pi：Ting Zhunext生成模型，以支持抗裂缝材料的设计，必须直接构建与纳米斯科群岛互动式键合的信息有关的信息。 面临的挑战是开发可以在如此小的尺度上解决行为的方法，但仍说明在结构应用（例如汽车，飞机，网球球拍等）中平均行为的各个方面。该项目将通过使用裂纹尖端或具有远距离场的界面附近的原子（分子动力学）在纳米级分析的缺陷来解决行为，从而使大量原子的平均影响以实现所谓的粗粒？描述。 通过这种方式，可以以足够高的长度和时间尺度进行模拟，以提供有关结构行为的有意义的信息，而界面的作用则以原子尺度的分辨率进行处理。这项研究有望实质上影响晶粒边界的结构和良好尺度微结构的结构，以影响金属合金的改善疲劳和薄型抗性。 疲劳是经受循环载荷的金属中的故障模式，该金属造成了昂贵的故障，例如高速公路桥梁，飞机尾部，发动机组件，铁路脱轨和许多其他例子。 通过开发更多的预测性工具来解决多晶（通常为五个数量级的五个数量级）之间在原子量表和谷物尺度之间建模和模拟工具的较大差距，从而可以实质性地储蓄和安全材料来衍生出的社会益处。 研究结果将纳入计算材料科学的本科课程，以及PI和Co-Pi教授的材料的缺陷和机械性能的研究生课程，从而加速了本项目中开发的技术的应用。