A New Method to Efficiently and Reliably Measure Ternary Diffusion Coefficients

一种高效、可靠测量三元扩散系数的新方法

• 批准号: 1904245
• 负责人: Ji-Cheng Zhao
• 金额: $ 35.9万
• 依托单位: University of Maryland, College Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1904245&HistoricalAwards=false
• 关键词: New; Method; Efficiently; Reliably; Measure

NON-TECHNICAL SUMMARY:Diffusion coefficients are a measure of how fast atoms jump and the speed of intermixing between different elements (atoms) at various temperatures, thus they are some of the most fundamental materials properties that materials engineers need to design new materials for enhanced performance which can lead to higher efficiency and lower emissions for many devices. For instance, diffusion coefficients dictate how much a jet engine turbine blade would elongate at high temperatures during high speed rotation (a phenomenon called creep). Efficient methods have been developed to measure the diffusion coefficients between two elements (referred to as binary systems), but no efficient methods exist to measure the speed of intermixing among three elements (ternary systems). This study aims to develop a revolutionary method to speed up the measurements of diffusion coefficients of ternary systems. Wide application of this new high-throughput ternary diffusion measurement methodology and algorithms will lead to much more data to build databases to accelerate the design of more advanced materials to enhance US manufacturing competitiveness. One graduate student from an underrepresented group will be trained towards her/his PhD degree under the support of this project. Two undergraduate research assistants from diverse backgrounds will also be hired to work on this project to excite their interest in structural metals and to allow them to gain research experience.TECHNICAL SUMMARY: In addition to binary diffusion coefficients, ternary diffusion coefficients are essential to the establishment of reliable diffusion and mobility databases for multicomponent systems. Each set of reliable ternary diffusion coefficients (with cross terms) at one composition are usually measured from the composition intersection point of two separate diffusion couples (paths), which leads to very low efficiency. Approaches to extract ternary diffusion coefficients from a single diffusion couple can lead to very large errors. The objective of this study is to establish a revolutionary new methodology to reliably measure ternary diffusion coefficients at unprecedented efficiency, including rigorous evaluations of the cross diffusion terms. The new stacked-couple diffusion multiples (SCDMs) have the capability to create numerous composition intersection points across the ternary composition space. Forward simulation analysis (FSA) of numerous composition profiles collected from each SCDM will allow extraction of reliable ternary diffusion coefficients across wide compositions in ternary systems. In essence, one SCDM can be used to collect reliable ternary diffusion coefficients of entire ternary systems. This study will demonstrate this new methodology and validate it using the Fe-Co-Ni ternary system for which reliable diffusion coefficients are available for a direct comparison. Copious new ternary diffusion coefficients will then be obtained for 10 ternary systems inside the Fe-Co-Ni-Cr-Cu system that is a good model system for high entropy alloys (multi-principal element alloys). During this study, approaches and algorithms for 2-dimensional ternary diffusion simulations with the presence of phase interfaces (e.g. bcc/fcc) will be developed to enable efficient and reliable extraction of ternary diffusion coefficients in multi-phase ternary systems. The new methodology will enable unprecedented efficiency in measuring reliable ternary diffusion coefficients for accelerated establishment of multicomponent diffusion (mobility) databases for accurate simulation of materials processes. Accurate kinetic simulations will help accelerate new materials design and processing optimization to enhance the US manufacturing competitiveness. The methodology may also be extended to systematically and efficiently measure diffusion coefficients of multicomponent (beyond ternary) systems in the future.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.

扩散系数是原子跳跃的速度以及不同温度下不同元素（原子）之间混合速度的度量，因此它们是材料工程师设计新材料以增强性能所需的一些最基本的材料特性，这可以为许多设备带来更高的效率和更低的排放。例如，扩散系数决定了喷气发动机涡轮机叶片在高速旋转期间的高温下将伸长多少（一种称为蠕变的现象）。已经开发了有效的方法来测量两种元素（称为二元系统）之间的扩散系数，但是不存在有效的方法来测量三种元素（三元系统）之间的混合速度。本研究旨在发展一种革命性的方法，以加快三元系扩散系数的测量。这种新的高通量三元扩散测量方法和算法的广泛应用将带来更多的数据来建立数据库，以加速更先进材料的设计，提高美国制造业的竞争力。一名来自代表性不足群体的研究生将在该项目的支持下接受博士学位培训。两名来自不同背景的本科生研究助理也将被聘请到这个项目上工作，以激发他们对结构金属的兴趣，并让他们获得研究经验。技术总结：除了二元扩散系数，三元扩散系数是必不可少的，以建立可靠的多组分系统的扩散和迁移率数据库。在一个组成下的每组可靠的三元扩散系数（具有交叉项）通常从两个单独的扩散对（路径）的组成交叉点测量，这导致非常低的效率。从单个扩散偶中提取三元扩散系数的方法会导致非常大的误差。本研究的目的是建立一种革命性的新方法，以前所未有的效率可靠地测量三元扩散系数，包括交叉扩散项的严格评估。新的堆叠耦合扩散多次波（SCDM）有能力在三元复合空间中产生许多复合交点。正向模拟分析（FSA）的许多组成配置文件收集每个SCDM将允许提取可靠的三元扩散系数在广泛的组成三元系统。从本质上讲，一个SCDM可以用来收集可靠的整个三元系的三元扩散系数。本研究将证明这种新的方法，并验证它使用的Fe-Co-Ni三元系的可靠的扩散系数可用于直接比较。在Fe-Co-Ni-Cr-Cu三元系中，得到了10个新的三元系的扩散系数，这是一个很好的高熵合金（多主元合金）模型体系。在这项研究中，方法和算法的2维三元扩散模拟与相界面（如bcc/fcc）的存在下，将开发，使有效和可靠的提取多相三元系统中的三元扩散系数。新方法将使测量可靠的三元扩散系数的效率达到前所未有的水平，从而加速建立多组分扩散（迁移率）数据库，以准确模拟材料过程。精确的动力学模拟将有助于加速新材料的设计和工艺优化，以提高美国制造业的竞争力。该方法也可以扩展到系统和有效地测量扩散系数的多组分（超越三元）systems.This奖反映了NSF的法定使命，并已被认为是值得通过评估使用基金会的智力价值和更广泛的影响审查标准的支持。

项目成果

Recommendations for simplified yet robust assessments of atomic mobilities and diffusion coefficients of ternary and multicomponent solid solutions

对三元和多组分固溶体的原子迁移率和扩散系数进行简化而稳健的评估的建议

• DOI: 10.1016/j.scriptamat.2021.114227
• 发表时间: 2022
• 期刊: Scripta Materialia
• 影响因子: 6
• 作者: Zhong, Wei;Zhao, Ji-Cheng
• 通讯作者: Zhao, Ji-Cheng

Diffusion Coefficients and Phase Equilibria of the Cu-Zn Binary System Studied Using Diffusion Couples

使用扩散偶研究铜锌二元体系的扩散系数和相平衡

• DOI: 10.1007/s11669-020-00831-3
• 发表时间: 2020
• 期刊: Journal of Phase Equilibria and Diffusion
• 影响因子: 1.4
• 作者: Eastman, Christopher M.;Zhang, Qiaofu;Zhao, Ji-Cheng
• 通讯作者: Zhao, Ji-Cheng

High-Throughput and Systematic Study of Phase Transformations and Metastability Using Dual-Anneal Diffusion Multiples

使用双退火扩散多次进行相变和亚稳态的高通量系统研究

• DOI: 10.1007/s11661-020-05915-w
• 发表时间: 2020
• 期刊: Metallurgical and Materials Transactions A
• 作者: Zhao, Ji-Cheng

A simple yet general model of binary diffusion coefficients emerged from a comprehensive assessment of 18 binary systems

• DOI: 10.1016/j.actamat.2021.117077
• 发表时间: 2021-08
• 期刊: Acta Materialia
• 影响因子: 9.4
• 作者: W. Zhong;Qiaofu Zhang;Ji-Cheng Zhao

Vacancy Wind Factor of Diffusion of 13 Binary Metallic Solid Solutions

13种二元金属固溶体扩散的空位风因子

• DOI: 10.1007/s11669-022-01013-z
• 发表时间: 2022
• 期刊: Journal of Phase Equilibria and Diffusion
• 影响因子: 1.4
• 作者: Zhong, Wei;Zhao, Ji-Cheng
• 通讯作者: Zhao, Ji-Cheng