Research Initiation Award: Multiscale modeling of the mechanical behavior and deformation mechanisms in small scale metallic structure exhibiting epitaxial interfaces

塔斯基吉大学的研究启动奖题为-显示外延界面的小型金属结构中的机械行为和变形机制的多尺度建模-目标是启动一个小型金属结构力学行为的多尺度建模研究计划，重点是界面和边界的处理。在这些长度尺度上，界面在控制结构的力学行为方面起着关键作用。然而，由于其复杂性和对所有长度尺度(原子、缺陷和微观结构)的依赖，对潜在的物理机制缺乏完整的理解。为此，该项目在两个尺度上启动了计算材料研究：使用分子动力学的纳米尺度和使用晶体塑性的介观尺度。这项工作将为界面创建和验证物理上知情的微观和中尺度计算模型。研究目标是建立并验证位错动力学(DD)框架，该框架解释外延异质结构中界面与位错之间的相互作用，包括位错的吸收、传输、形核和核心扩展；并使用“界面增强型”DD框架进行严格控制的虚拟实验，以评估粘塑性自洽多晶塑性模型对本研究中所述相同类型界面的解释能力。为了帮助实现这些目标，与密西西比州立大学先进车辆系统中心经验丰富的多尺度建模团队建立了长期合作关系。该项目将导致建立一个计算力学项目，为本科生提供协同研究活动，并将建模和模拟融入塔斯基吉大学的机械工程课程。该项目还将记录指导做法并收集数据，为今后通过深入研究工程学扩大少数族裔学生的参与奠定基础。

Tuskegee University's Research Initiation Award entitled - Multiscale Modeling of the Mechanical Behavior and Deformation Mechanisms in Small Scale Metallic Structure Exhibiting Epitaxial Interfaces - has the goal to initiate a research program in multiscale modeling of the mechanical behavior of small scale metallic structures, with a focus on the treatment of interfaces and boundaries. Interfaces play a critical role in governing the mechanical behavior of structures at those length scales. However, a complete understanding of the underlying physical mechanisms is missing due to their complexity and dependence on all length scales: atomic, defect, and microstructure. To this end, the project initiates computational materials research at two scales: nanoscale, using molecular dynamics, and mesoscale, using crystal plasticity. The work will create and validate physically informed micro and mesoscale computational models for interfaces. The research objectives are to create and validate a dislocation dynamics (DD) framework which accounts for the interaction of interfaces with dislocations in epitaxial heterogeneous structures, including dislocation absorption, transmission, nucleation, and core spreading; and to use the "interface-enhanced" DD framework to perform carefully controlled virtual experiments to evaluate the ability of the viscoplastic self-consistent polycrystalline plasticity model to account for the same type of interfaces addressed in this research. To help accomplish these objectives, a collaboration with the experienced multiscale modeling team at the Center of Advanced Vehicular Systems at Mississippi State University has been forged with a long-term relationship in mind.The project will lead to establishing a computational mechanics program, providing synergistic research activities to undergraduate students, and infusing modeling and simulation into the mechanical engineering curriculum at Tuskegee University. The project will also document the mentoring practices and collect data to set the stage for future research on broadening the participation of minority students through intensive research in engineering.