CAREER: Order-induced heterogeneities in the deformation behavior of FCC concentrated solid solutions

职业：FCC 浓固溶体变形行为中的有序诱导异质性

• 批准号: 2144451
• 负责人: Matthew Daly
• 金额: $ 57.76万
• 依托单位: University of Illinois at Chicago
• 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: 2022-08-15 至 2027-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2144451&HistoricalAwards=false
• 关键词: CAREER; Order; induced; heterogeneities; deformation

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2).Non-technical SummaryThe realization of new, stronger materials is a critical element to the success of emerging technologies in a diverse set of application areas including civil infrastructure, automotive, and aerospace. For example, the ranges of electric vehicles can be improved with stronger alloys (i.e., mixtures of metals and additives), by enabling lower weight vehicle components without a compromise to passenger safety. One key pathway to improving strength is through an understanding of how alloys deform (i.e., respond to loading). Traditional understanding emphasizes the importance of additive chemistry and concentration in directing deformation. However, this rationale has shortcomings in explaining the behavior of alloys with unusually large concentrations of additives. These concentrated alloys include many technologically important materials such as high strength steels. To address these shortcomings, this research effort explores the following question: How does the atomic-scale organization of additives in concentrated alloys influence how the alloy bends? This question is motivated by the hypothesis that, in addition to chemistry and concentration, the additive organization play an important and under-recognized role in directing bending. To reveal this link, forefront mechanical testing techniques and computational models are developed and used. In addition to advancing tools for materials testing, this effort provides new fundamental insights for how these special class of alloys bend, that provides a foundational understanding to engineer materials with improved strength. More broadly, the outcomes of this effort deliver key datasets and methodologies, which enable new investigations within the research community, and contribute to the competitive advantage of America’s advanced manufacturing industries. These findings are the basis of virtual reality-based learning materials for undergraduate education, and middle- and high-school outreach. The objective of these instructional activities is to broaden participation in science, technology, engineering and mathematics (STEM) by leveraging virtual reality (VR) as a tool to convey materials scientific concepts to a broad range of students. Another intended outcome of these activities is the recruitment of students, including those from underrepresented groups, to participate in the research tasks of this effort, and thereby enhance the STEM pipeline.  Technical SummaryThe research focuses on the following question: How does the length scale of solute organization drive the deformation behavior of concentrated solid solutions? Within the context of concentrated systems, the motivation for this effort is the observed fluctuations in solute potential energies that emerge at the length scale of dislocations. These fluctuations underpin the central hypothesis of this investigation – that is, chemical short-range order gives rise to predictable, statistical heterogeneities in the potential energy landscape of concentrated solid solutions that influence the competition between various deformation mechanisms. To answer the question above, complementary experimental, including a nanobending testing technique, and computational research tools, such as scale-bridging kinetic Monte Carlo simulation, are being developed and utilized. The face-centered cubic CrCoNi system is selected as a benchmark for this investigation, yet the approach can be generalized to other concentrated systems of scientific and technological interest. Specific outcomes from this effort include 1) deformation mechanism maps that chart the trends in mechanism competition using chemical ordering as a structural parameter; 2) statistical relationships that link chemical short-range order with the length scale-resolved fluctuations in the potential energy barriers of deformation processes; and 3) a new experimental-computational approach to measure mesoscale deformation that bridges the temporal and spatial gap between simulations and theory. More broadly, the outcomes of this effort provide the research community with new tools to explore multiscale relationships in complex alloys, and key experimental datasets to validate interatomic potentials. The education and outreach activities feature virtual reality (VR) modules in order to illustrate concepts such as atomic packing, solid solution formation and slip.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.

该奖项全部或部分由《2021年美国救援计划法案》（公法117-2）资助。实现新型、更坚固的材料是新兴技术在民用基础设施、汽车和航空航天等多种应用领域取得成功的关键因素。例如，电动汽车的行驶里程可以通过使用更强的合金（即金属和添加剂的混合物）来提高，从而在不损害乘客安全的情况下实现更轻的车辆部件。提高强度的一个关键途径是通过了解合金如何变形（即对载荷的响应）。传统的认识强调添加剂化学和浓度在指导变形中的重要性。然而，这一理论在解释含有异常高浓度添加剂的合金的行为时存在缺陷。这些浓缩合金包括许多技术上重要的材料，如高强度钢。为了解决这些缺点，本研究探索了以下问题：浓缩合金中添加剂的原子级组织如何影响合金的弯曲方式？提出这个问题的动机是这样一种假设，即除了化学和浓度之外，添加剂组织在指导弯曲方面起着重要的作用，但尚未得到充分认识。为了揭示这种联系，开发和使用了最先进的力学测试技术和计算模型。除了先进的材料测试工具外，这项工作还为这些特殊类别的合金如何弯曲提供了新的基本见解，从而为提高强度的工程材料提供了基础理解。更广泛地说，这一努力的成果提供了关键的数据集和方法，使研究界能够进行新的调查，并有助于美国先进制造业的竞争优势。这些发现是基于虚拟现实的学习材料用于本科教育和初中和高中推广的基础。这些教学活动的目标是通过利用虚拟现实（VR）作为向广大学生传达材料科学概念的工具，扩大对科学、技术、工程和数学（STEM）的参与。这些活动的另一个预期结果是招募学生，包括来自代表性不足群体的学生，参与这项工作的研究任务，从而加强STEM管道。本研究主要围绕以下问题展开：溶质组织的长度尺度如何驱动浓缩固溶体的变形行为？在集中系统的背景下，这种努力的动机是观察到的在位错长度尺度上出现的溶质势能的波动。这些波动支撑了本研究的中心假设——即，化学短程秩序在浓缩固溶体的势能格局中产生了可预测的、统计上的异质性，从而影响了各种变形机制之间的竞争。为了回答上述问题，正在开发和利用互补的实验，包括纳米弯曲测试技术和计算研究工具，如尺度桥接动力学蒙特卡罗模拟。面心立方CrCoNi系统被选为本研究的基准，但该方法可以推广到其他科学和技术兴趣的集中系统。这项工作的具体成果包括：1)变形机制图，利用化学排序作为结构参数绘制机制竞争的趋势；2)化学短程有序与变形过程中长度尺度分辨的势能势垒波动之间的统计关系；3)一种新的测量中尺度变形的实验-计算方法，弥合了模拟与理论之间的时空差距。更广泛地说，这项工作的结果为研究界提供了探索复杂合金中多尺度关系的新工具，以及验证原子间相互作用势的关键实验数据集。教育和推广活动以虚拟现实（VR）模块为特色，以说明原子包装，固溶体形成和滑动等概念。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

The Competition Between Deformation Twinning and Dislocation Slip in Deformed Face-Centered Cubic Metals

• DOI: 10.1007/s11837-022-05437-3
• 发表时间: 2022-08-15
• 期刊: JOM
• 影响因子: 2.6
• 作者: Jagatramka, Ritesh;Daly, Matthew
• 通讯作者: Daly, Matthew

The evolution of deformation twinning microstructures in random face-centered cubic solid solutions

• DOI: 10.1063/5.0135538
• 发表时间: 2023-02
• 期刊: Journal of Applied Physics
• 影响因子: 3.2
• 作者: Ritesh Jagatramka;Junaid Ahmed;M. Daly

An analytical method to quantify the statistics of energy landscapes in random solid solutions

• DOI: 10.1016/j.commatsci.2022.111763
• 发表时间: 2022-02
• 期刊: Computational Materials Science
• 影响因子: 3.3
• 作者: Ritesh Jagatramka;C. Wang;M. Daly