Fundamental Insights into Multi-element Grain Boundary Segregation in Nanocrystalline Alloys

纳米晶合金中多元素晶界偏析的基本见解

• 批准号: 2343682
• 负责人: Fadi Abdeljawad
• 金额: $ 25.79万
• 依托单位: Lehigh University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-10-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2343682&HistoricalAwards=false
• 关键词: Fundamental; Insights; into; Multi; element

NONTECHNICAL SUMMARYThis award supports research and educational activities aimed at gaining fundamental insights into the segregation of multiple elemental species to grain boundaries, and how it affects grain growth in nanocrystalline metallic alloys. Nearly all functional and structural materials are polycrystalline systems; they are composed of differently oriented crystalline grains that are joined at internal interfaces, termed grain boundaries. The grain size and distribution in a metal greatly influences many engineering properties, including mechanical, thermal, and electrical. For example, the mechanical strength of a metal increases rapidly with decreasing grain size. However, due to their small grain size and high density of grain boundaries, nanocrystalline materials are usually structurally unstable. As a result, they undergo rapid grain growth, which limits their use in many technological applications. In this project, the PI will investigate the segregation of multiple types of elemental species to grain boundaries and its role in grain growth in multi-component alloys. The research involves theoretical development and numerical implementation of mathematical models that will be used to simulate the dynamics of grain boundary segregation and grain growth kinetics. A primary focus of this project will be on metallic alloys composed of three different types of elements. Lying at the intersection of materials science and applied mathematics, this project will impact numerous areas of materials physics, chemical thermodynamics, and nanotechnology. Further, this project will provide an avenue to train future-generation of engineers and scientists with the skill set necessary for careers in knowledge-intensive industries in South Carolina, which is an emerging technology and manufacturing hub. The PI will design an “Atomic Legos” outreach activity to engage K-12 students in materials science and help them learn about crystals and metals. This project leverages Clemson’s “Creative Inquiry” program in order to involve undergraduate students, particularly women and underrepresented groups, in scientific research.TECHNICAL SUMMARYThis award supports the development of a mesoscale theoretical and computational modeling framework aimed at advancing our fundamental understanding of the segregation of multiple types of elemental species to grain boundaries and its role in grain growth and thermal stability of nanocrystalline metallic alloys. Owing to their nanoscale grain size, nanocrystalline materials exhibit a unique combination and properties and functionalities. However, rampant grain growth during materials processing or under service conditions is considered one of the main hurdles to the large-scale use of nanocrystalline metals in many engineering technologies. In this project, the PI aims to elucidate key multi-element grain boundary segregation mechanisms that control grain boundary migration and grain growth in metallic alloys. Specific goals of this project include: (1) Development of a theoretical and computational phase field model of multi-element grain boundary segregation in multi-component alloys that accounts for bulk and interface thermodynamics and is able to simulate the microstructural evolution over diffusive scales; (2) Perform theoretical analysis and computational studies to quantify the thermodynamic and kinetic effects of multi-element grain boundary segregation on the thermal stability of nanocrystalline alloys; (3) Quantify the role of the grain boundary network effect in solute partitioning and distribution within grain microstructures. Lying at the intersection of materials science and applied mathematics, this project will impact numerous areas of materials physics, chemical thermodynamics, and nanotechnology. Further, this project will provide an avenue to train future-generation of engineers and scientists with the skill set necessary for careers in knowledge-intensive industries in South Carolina, which is an emerging technology and manufacturing hub. The PI will design an “Atomic Legos” outreach activity to engage K-12 students in materials science and help them learn about crystals and metals. This project leverages Clemson’s “Creative Inquiry” program in order to involve undergraduate students, particularly women and underrepresented groups, in scientific research.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.

非技术摘要这一奖项支持研究和教育活动，旨在获得对多种元素物种隔离到晶界的隔离的基本见解，以及它如何影响纳米晶金属合金的晶粒生长。几乎所有功能和结构材料都是多晶系统。它们由在内部界面（称为晶界）连接的不同定向的晶粒。金属中的晶粒尺寸和分布极大地影响了许多工程特性，包括机械，热和电气。例如，金属的机械强度随着晶粒尺寸的减小而迅速增加。但是，由于其晶粒尺寸较小和晶界的高密度，纳米晶体材料通常在结构上不稳定。结果，它们经历了快速的谷物生长，这限制了它们在许多技术应用中的使用。在该项目中，PI将研究多种类型的元素物种对晶界的分离及其在多组分合金中晶粒生长中的作用。该研究涉及数学模型的理论发展和数值实施，这些模型将用于模拟晶界分离和晶粒生长动力学的动力学。该项目的主要重点将放在由三种不同类型的元素组成的金属合金上。该项目位于材料科学与应用数学的交汇处，将影响材料物理学，化学热力学和纳米技术的许多领域。此外，该项目将提供一条途径，以培训工程师和科学家的未来生成，并为南卡罗来纳州知识密集型行业的职业所必需的技能设置，这是一种新兴的技术和制造中心。 PI将设计一种“原子乐高”外展活动，以吸引K-12学生参与材料科学，并帮助他们了解晶体和金属。该项目利用克莱姆森（Clemson）的“创造性探究”计划，以使本科生，尤其是妇女和代表性不足的群体参与科学研究。技术摘要颁发奖项支持介绍理论和计算模型框架的发展，旨在发展旨在提高我们在元素范围内的元素范围的基本理解，并促进晶粒范围的基本范围，并促进晶粒范围的基本范围，并且纳米晶金属合金。由于其纳米级晶粒尺寸，纳米晶材料具有独特的组合以及特性和功能。但是，在材料加工或在服务条件下的材料加工过程中，谷物的生长猖ramp被认为是在许多工程技术中大规模使用纳米晶金属的主要障碍之一。在该项目中，PI旨在阐明控制金属合金中晶界迁移和晶粒生长的关键多元素晶界隔离机制。该项目的具体目标包括：（1）在多组分合金中开发多元素晶界隔离的理论和计算相位场模型，这些合金构成了体积和界面热力学，并能够模拟微观结构的进化而不是分化量表； （2）进行理论分析和计算研究，以量化多元素晶界分离对纳米晶合金热稳定性的热力学和动力学作用； （3）量化晶界网络效应在晶粒微观结构内实心分配和分布中的作用。该项目位于材料科学与应用数学的交汇处，将影响材料物理学，化学热力学和纳米技术的许多领域。此外，该项目将提供一条途径，以培训工程师和科学家的未来生成，并为南卡罗来纳州知识密集型行业的职业所必需的技能设置，这是一种新兴的技术和制造中心。 PI将设计一种“原子乐高”外展活动，以吸引K-12学生参与材料科学，并帮助他们了解晶体和金属。该项目利用克莱姆森（Clemson）的“创造性探究”计划，以使本科生，尤其是妇女和代表性不足的群体参与科学研究。该奖项反映了NSF的法定任务，并通过使用基金会的知识分子优点和更广泛的影响来审查标准，通过评估来诚实地对其进行评估。