Multi-Scale Experimental and Computational Investigation of Microscale Origins of Ductile Failure

延性破坏微观起源的多尺度实验和计算研究

• 批准号: 2334678
• 负责人: Allison Beese
• 金额: $ 65.43万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-05-01 至 2027-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2334678&HistoricalAwards=false
• 关键词: Multi; Scale; Experimental; Computational; Investigation; Multi; Scale; Experimental; Computational; Investigation

Metals are exposed to countless scenarios in service in which ductile fracture leads to early failure. This award supports fundamental research to understand the origins of this failure type in engineering metals. Using experiments, computational simulations, and data science approaches, the research aims to identify links between key features in the microstructure of metals and their propensity for failure under a wide range of real-world loading conditions. The research findings will enable the more efficient use of existing materials and the design of new materials with tailored microstructures for superior damage tolerance, energy absorption, or fracture performance. These features are key to enabling increased component safety, cost savings, and reduced environmental footprint. The award will provide education and training at undergraduate and graduate levels through student research and will build on an existing partnership with Clark Atlanta University through a faculty/student exchange program and hands-on workshops.The primary goal of this research is to quantitatively determine how multiaxial stress states, modified by local microstructure (grain misorientation and neighborhoods), promotes the development of dislocation structures that result in conditions directly preceding void nucleation in metals. While it is known that engineering measures of failure strain vary with stress state, how local microstructural features alter stress states resulting in fracture initiation is not well understood. The researchers will use experimental measurements (in situ scanning electron microscopy and synchrotron X-ray diffraction) and computational simulations (crystal plasticity and dislocation dynamics) analyzed through advanced regression methods to determine the relative importance and/or coupling of material, microstructural, and stress state features on ductility exhaustion of metals. By unraveling the intertwined roles of these effects, this research will enable the future development of novel fracture criteria that include explicit microstructural descriptions, facilitating the full use of current alloys and the development of superior materials.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.

金属暴露于无数的服务中，延性裂缝会导致早期失败。该奖项支持基本研究，以了解工程金属中这种故障类型的起源。该研究使用实验，计算模拟和数据科学方法，旨在确定金属微观结构中的关键特征及其在各种现实世界加载条件下的失败倾向之间的联系。研究发现将使现有材料更有效地使用，并设计具有量身定制的微观结构的新材料，以实现出色的损伤，能量吸收或断裂性能。这些功能是提高组件安全性，节省成本和降低环境足迹的关键。该奖项将通过学生研究在本科和研究生级别提供教育和培训，并通过教师/学生交流计划和动手讲习班与克拉克·亚特兰大大学的现有合作伙伴关系。这项研究的主要目标是定量确定多用途压力状态，通过局部微结构（谷物错误和邻里）的促进效应的促进构成的结构，从而确定了如何通过本地微观结构（谷物错误和邻里）进行了修改。虽然众所周知，失败菌株的工程测量与应力状态有所不同，但局部微结构特征如何改变应力状态导致骨折起始的压力状态。研究人员将使用实验测量（原位扫描电子显微镜和同步X射线衍射）以及通过先进的回归方法分析的计算模拟（晶体可塑性和脱位动力学）来确定对材料，微结构和压力状态的相对重要性和/或对金属延性的材料，微结构和压力状态的特征。通过揭开这些效果的相互交织的作用，这项研究将使新的裂缝标准的未来发展，包括明确的微观结构描述，促进了当前合金的全部使用和卓越材料的发展。这项奖项反映了NSF的法定任务，并通过评估基础的智力效果和宽阔的范围来进行评估，并具有评估。