DMREF/Collaborative Research: Grain Interface Functional Design to Create Damage Resistance in Polycrystalline Metallic Materials

DMREF/合作研究：晶粒界面功能设计以提高多晶金属材料的抗损伤能力

• 批准号: 2118673
• 负责人: Siddhartha Pathak
• 金额: $ 48.48万
• 依托单位: Iowa State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-01-01 至 2025-12-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2118673&HistoricalAwards=false
• 关键词: DMREF; Collaborative; Research; Grain; Interface

Even though polycrystalline metallic materials are ubiquitous in daily life, when and where metallic structural components damage and fail is difficult to predict, which generally leads to overdesign. One form of damage – ductile damage – takes place in materials which are easily plastically deformed by formation of voids and localized shear bands. The initiation of these voids is strongly influenced by the internal constitution of the aggregate composite made up of single crystals comprising the polycrystalline metal. High-purity metals often form voids at the boundaries between single crystals, but it is not known why. This Designing Materials to Revolutionize and Engineer our Future (DMREF) award supports the fundamental study of voids-based ductile damage in high-purity metals to enable the manufacture of materials for specific applications with significantly reduced propensity for void formation. In addition, this project will facilitate collaboration with the Air Force Research Laboratory to pursue design of new materials and manufacturing techniques for strategic purposes. This highly collaborative project will also allow students the opportunity to engage on three campuses, the Air Force Research Laboratory, and a couple of Department of Energy Laboratories to assist in educating the next generation of scientists and engineers in strategically important disciplines. Designing material interfaces to resist formation of voids during tensile deformation will be a significant contribution to the Materials Genome Initiative. This award addresses control of feature and defect character as well as the internal stress state for the design and manufacture of polycrystalline metals against failure. Ductile damage generally includes the processes of void nucleation, growth, and coalescence in addition to localized shear banding. This project is for a new three-dimensional sample design for both rod and plate forms of material, which will be a surrogate for a general structural component for large deformation. High-purity refractory body-centered cubic tantalum is selected as the model material due to its potential for extreme environment use. This material is known to form voids predominantly at grain boundaries and will be the focal point of material design through advanced manufacturing processes. The material design process will include the highly interactive elements of nano, micro and macro-scale experiments at varying strain rates and temperatures, molecular dynamics simulations, thermodynamically consistent plasticity and theory development, micro-scale polycrystal simulations, and macro-scale damage simulations for component design. The highlight of the approach is the uncertainty quantification via machine learning for self-consistent consolidation of large experimental and simulation datasets to guide material design and manufacturing process. The goal of this project is to design a manufacturing process to produce material which reduces damage by 30% over that in the as-received and annealed state.This project is jointly funded by the Division of Civil, Mechanical and Manufacturing Innovation (CMMI) in the Directorate for Engineering (ENG), the Divisions of Materials Research (DMR) and Mathematical Sciences (DMS) in the Directorate for Mathematical and Physical Sciences (MPS), and the Established Program to Stimulate Competitive Research (EPSCoR).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

尽管多晶金属材料在日常生活中随处可见，但金属结构构件在何时何地发生损伤和失效是很难预测的，这通常会导致过度设计。一种形式的损伤-延性损伤-发生在材料中，这些材料很容易通过形成空洞和局部剪切带而塑性变形。这些空洞的形成强烈地受到由含有多晶金属的单晶组成的聚集体复合材料的内部组成的影响。高纯度金属经常在单晶之间的边界形成空洞，但原因尚不清楚。这项旨在革新和设计我们的未来的设计材料奖(DMREF)支持对高纯金属中基于孔洞的延性损伤的基础研究，以使制造用于特定应用的材料能够显著减少空洞形成的倾向。此外，该项目将促进与空军研究实验室的合作，为战略目的进行新材料和制造技术的设计。这个高度协作的项目还将允许学生有机会参与三个校区、空军研究实验室和能源部的几个实验室，以帮助培养具有战略重要性的学科的下一代科学家和工程师。设计材料界面以防止在拉伸变形过程中形成空洞将是对材料基因组倡议的重大贡献。该奖项涉及针对多晶金属的设计和制造的特征和缺陷特征以及内部应力状态的控制。韧性损伤除局部剪切带外，一般还包括空洞形核、长大和合并的过程。该项目是一个新的三维样本设计的杆和板的形式的材料，这将是一个大变形的一般结构部件的替代品。高纯耐火体心立方钽因其在极端环境中的潜在用途而被选为模型材料。众所周知，这种材料主要在晶界形成空洞，并将成为通过先进制造工艺进行材料设计的焦点。材料设计过程将包括在不同应变率和温度下的纳米、微观和宏观尺度实验的高度交互的元素，分子动力学模拟，热力学一致塑性和理论发展，微观多晶模拟，以及用于部件设计的宏观损伤模拟。该方法的亮点是通过机器学习对大量实验和模拟数据集的自洽合并进行不确定性量化，以指导材料设计和制造过程。这个项目的目标是设计一种制造工艺，使材料的制造过程比接收和退火状态下的损伤减少30%。该项目由工程局(ENG)的土木、机械和制造创新部门(CMMI)、数学和物理科学局(MPS)的材料研究部门(DMR)和数学科学部门(DMS)以及已建立的刺激竞争研究计划(EPSCoR)共同资助。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。