GOALI: Microstructure-Sensitive Design of Multiphase Structural Alloys

该学术与工业联络资助机会（GOALI）项目将材料微结构级建模和仿真与材料加工、表征以及材料性能测量协议和数据分析的最新进展相结合，以实现下一代航空航天结构中α - β钛合金的更快速搜索、评估和设计探索。工作重点是实现这一目标所必需的三个不发达的技术：(i)三维微观结构数据采集、统计分析、压缩和重建的协议；（ii）弹性刚度、最小强度、疲劳和断裂性能作为真实或虚拟微观结构显著特征的函数的估计；（iii）更准确的晶粒/相尺度模型，包括晶粒和相边界的影响。这是第一个模拟支持的材料设计研究，涉及具有大量微观结构形态的α - β钛合金系统的多个性能目标。该项目增加了(i)材料知识系统扩展到多晶和多相塑性，以实现快速设计探索；（ii）将球形纳米压痕原位阵列与单个相和界面区域的晶体塑性模型耦合，以开发更多基于物理的单个相和界面滑移传递的晶体塑性模型。（iii）采用归纳设计探索方法作为指导参数模拟策略的手段，以探索相互冲突的材料性能目标的设计空间。这项工作的好处包括将新型和改进材料的建模和仿真信息设计从超级计算带到桌面计算环境，从而实现了一种实用的工程方法来设计探索潜在的大型微结构集，以解决所需的多个属性目标。与材料基因组计划相关的未来劳动力将受益于研究生的直接支持，本科生的研究经验，并将结果纳入佐治亚理工学院（美国最大的工程项目）的材料建模和设计课程。基于这一基础研究，鉴于双相α - β Ti结构合金体系在航空航天工业中的重要作用，预计波音公司将在其工程分析和设计实践中纳入相关元素。

This Grant Opportunity for Academic Liaison with Industry (GOALI) project combines material microstructure-level modeling and simulation with materials processing, characterization and recent advances in materials property measurement protocols and data analytics to realize more rapid search, evaluation and design exploration of alpha-beta titanium alloys for next generation aerospace structures. The work focuses on three underdeveloped technologies necessary to achieve this goal: (i) protocols for three-dimensional microstructure data acquisition, statistical analyses, compression, and reconstruction, (ii) estimates of elastic stiffness, minimum strength, fatigue and fracture properties as a function of the salient features in real or virtual microstructures, and (iii) more accurate grain/phase scale models, including effects of grain and phase boundaries. This is the first simulation-supported materials design study involving multiple property objectives for alpha-beta titanium alloy systems with a substantial range of microstructure morphologies. This project adds (i) the Materials Knowledge System extension to polycrystal and polyphase plasticity to achieve rapid design exploration, (ii) coupling in situ arrays of spherical nanoindentation with crystal plasticity models of individual phases and interface regions to develop more physically based crystal plasticity models for the individual phases and interface slip transfer, and (iii) pursuing the Inductive Design Exploration Method as a means of guiding the strategy for parametric simulations to explore the design space for conflicting material property goals.The benefits of this work include bringing modeling and simulation-informed design of new and improved materials from the supercomputing to the desktop computing environment, thereby enabling a practical engineering approach to design exploration of a potentially large set of microstructures to address desired multiple property targets. The future workforce relevant to the Materials Genome Initiative will benefit through the graduate students receiving direct support, undergraduate research experiences, and incorporation of results into materials modeling and design courses at Georgia Tech, the nation's largest engineering program. Based on this foundational research, it is expected that Boeing will incorporate relevant elements into its engineering analysis and design practice given the important role of the dual phase alpha-beta Ti structural alloy system in the aerospace industry.