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-机械行为和变形机制的多尺度建模在小尺度金属结构展示外延界面-的目标是启动一个研究计划，在多尺度建模的小尺度金属结构的机械行为，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的依赖性，对潜在的物理机制缺乏完整的理解：原子，缺陷和微观结构。为此，该项目启动了两个尺度的计算材料研究：纳米尺度，使用分子动力学，和中尺度，使用晶体塑性。 这项工作将创建和验证界面的物理信息微观和中尺度计算模型。研究目标是建立和验证一个位错动力学（DD）框架，该框架解释了外延异质结构中界面与位错的相互作用，包括位错吸收、传输、成核和芯扩展;并使用“界面增强”的DD框架进行仔细控制的虚拟实验，以评估粘塑性自一致的多晶塑性模型来解释本研究中所讨论的相同类型的界面。 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。该项目将导致建立计算力学计划，为本科生提供协同研究活动，并将建模和仿真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来扩大少数民族学生参与的研究奠定基础。

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.