RII Track-4: NSF: Understanding the Nanoscale Incommensurate Modulated Structure in the Titanium Alloys

RII Track-4：NSF：了解钛合金中的纳米级不相称调制结构

• 批准号: 2229724
• 负责人: Yufeng Zheng
• 金额: $ 23.4万
• 依托单位: Board of Regents, NSHE, obo University of Nevada, Reno
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-02-01 至 2024-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2229724&HistoricalAwards=false
• 关键词: RII; Track; NSF; Understanding; Nanoscale

This grant supports the fundamental research focusing a novel metal designing strategy and promotes the progress of materials science and technology. Metals are widely used structural materials because of their excellent performance under different loading conditions. However, to achieve synergetic combination of high strength and ductility in metals is essential but difficult. This project aims to investigate a new strategy to overcome the strength-ductility tradeoff in titanium (Ti) alloys by forming precipitates with a well-controlled length scale of spatial heterogeneities (i.e., heterogeneous precipitate structure). The project will identify the critical roles of nanostructures in forming the heterogeneous precipitate structure in Ti alloys using the cutting-edge transmission electron microscopy. The fellowship will allow the PI and a graduate student to visit the nation’s premier electron microscopy center, the MIT.nano research facilities at Massachusetts Institute of Technology. The project will enable the PI to establish a long-term collaboration with MIT.nano and new expertise in materials characterization, that will lead to a long-lasting impact on the research capability at University of Nevada, Reno (UNR). The PI will design new electron microscopy and materials science education modules for students at UNR and outreach activities for K-12 students in the Reno community to impact a young generation of learners, especially those from groups traditionally underrepresented in. STEM.This Research Infrastructure Improvement Track-4 EPSCoR Research Fellows (RII Track-4) project would provide a fellowship to an Assistant Professor and training for graduate student at the University of Nevada Reno (UNR). Utilizing nanostructures is an effective method to tune the size of precipitates in Ti alloys. In this project, the PI will use nanoscale incommensurate modulated structure (NIMS) as an example to identify the correlations between the local structure, composition and heterogeneous precipitate structure related to NIMS in Ti alloys. The goal of this research is to fundamentally understand the NIMS and its influence on the microstructure evolution during thermal treatment in the Ti alloys. Two specific research aims will be pursued: (i) Identifying the relationship between the alloy composition, processing parameter and the formation mechanism of the NIMS in Ti alloys; and (ii) Demonstrating the role of NIMS in ω and α phase precipitation during heat treatment in Ti alloys. The proposed research is built on the collaboration with the world-leading nanostructured materials scientist and the nation’s premier electron microscopy center at Massachusetts Institute of Technology. We will identify the atomic-level structure and composition characterization of NIMS using the aberration-corrected Themis Z G3 S/TEM and demonstrate the influence of NIMS on microstructure evolution pathways in Ti alloys using the DENS Solution Lightning in-situ TEM heating holder. The integration of highly advanced ex- and in-situ characterization tools is essential for an accurate description of these complex phase transformations in Ti alloys. The successful completion of the proposed project will advance the fundamental understanding of the microstructure evolution related to the nanostructures in Ti alloys, that is critical for accelerating the discovery and development of Ti alloys with a new composition and microstructure.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.

该赠款支持重点的基础研究，重点是一种新型的金属设计策略，并促进了材料科学和技术的进步。金属在不同的载荷条件下具有出色的性能，因此是广泛使用的结构材料。但是，要实现金属中高强度和延展性的协同组合是必不可少的，但很困难。该项目旨在调查一种新的策略，以克服钛合金（TI）合金的强度脱牙性折衷，并用空间异质性的长度尺度（即异质的精度结构）形成精确度。该项目将使用尖端的透射电子显微镜确定纳米结构在Ti合金中形成异质精度结构中的关键作用。该奖学金将使PI和研究生能够参观美国马萨诸塞州理工学院的MIT.NANO研究设施。该项目将使PI能够与MIT.NANO和材料表征的新专业知识建立长期合作，这将对内华达大学里诺大学（UNR）的研究能力产生长期影响。 The PI will design new electronic microscopy and materials science education modules for students at UNR and outreach activities for K-12 students in the Reno community to impact a young generation of learners, Especially those from groups traditionally underrepresented in. STEM.This Research Infrastructure Improvement Track-4 EPSCoR Research Fellows (RII Track-4) project would provide a fellowship to an Assistant Professor and training for graduate student at the University of Nevada Reno （UNR）。利用纳米结构是调整Ti合金中贵重物大小的有效方法。在该项目中，PI将使用纳米级不增压调制结构（NIMS）作为一个示例，以确定与Ti合金中与NIMS相关的局部结构，组成和异质沉淀结构之间的相关性。这项研究的目的是从根本上了解NIMS及其对TI合金热处理过程中微观结构演化的影响。将追求两个具体的研究目的：（i）确定合金组成，加工参数和NIMS中NIMS的形成机制之间的关系； （ii）证明NIMS在Ti合金中热处理过程中NIMS在ω和α相沉淀中的作用。拟议的研究建立在与世界领先的纳米结构材料科学家和马萨诸塞州理工学院的首要电子显微镜中心的合作基础上。我们将使用经过异常的themis Z G3 s/tem确定NIM的原子级结构和组成表征，并使用dens溶液闪电在Ti合金中证明NIMS对TI合金中微结构演化途径的影响。高度先进的前和原位表征工具的集成对于对Ti合金中这些复杂相变的准确描述至关重要。拟议项目的成功完成将提高对与Ti合金中纳米结构相关的微观结构进化的基本理解，这对于通过新的组成和微观结构的发现和开发至关重要，这是NSF的法定任务，并通过评估了Intellitial Intellit and Intformitial and Intformitial and Intfulitial and Intfulitial and Infcorne and Intfulitial and Intfulitial and Intfulitial and Intfulitial and Intfultial and Intfultial and Interviatial and Interviatial and Interviatial and Intfultial and Interviatial and Interviatial。