Collaborative Research: Revealing the Role of Vacancy Order in Regulating the Dislocation Behavior in Transition Metal Carbides

合作研究：揭示空位序在调节过渡金属碳化物位错行为中的作用

• 批准号: 2026760
• 负责人: Gregory Thompson
• 金额: $ 38.05万
• 依托单位: University of Alabama Tuscaloosa
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-08-15 至 2025-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2026760&HistoricalAwards=false
• 关键词: Collaborative; Research; Revealing; Role; Vacancy

NON-TECHNICAL DESCRIPTION: Transition metal carbides are a class of ceramics that have a wide range of uses including cutting materials, nuclear energy, and coatings. These applications subject these materials to both temperature and mechanical loads, which they must withstand in service. This project investigates the role of chemistry and crystal structure in controlling the mechanical mechanisms responsible for these properties. Through this project, graduate students will be trained to test, characterize, model and predict the mechanical behavior of transition metal carbides. Those students typically find employment in the energy, defense, and aerospace sectors of society. In addition, this project develops secondary education learning modules that explain hardness, as a technical definition, to middle and high school students.TECHNICAL DETAILS: The transition metal carbides are known to have unique mechanical properties which are intimately linked to their chemistry and structure. This project investigates how this chemistry, and specifically the order of the carbon atoms, controls the mechanical mechanisms responsible for peculiar anomalous hardening and low temperature creep in these carbides. The experimental and computational research develops synergic support in elucidating the fundamental mechanics of dislocations in these ceramics relative to temperature, chemistry, and most importantly, the order of the non-metal sublattice. This project provides, for the first time, a description of the mechanical properties in terms of chemical order using the order parameter. This project is particularly relevant now given the importance of these materials for use in the energy, aerospace, and defense industries, especially the area of applied hypersonics. Furthermore, understanding the mechanistic link for such mechanical properties will aid the development of new compositionally complex transition metal carbides. Given the nature of the research, the graduate students are trained in an integrated manner for the two complementary areas - advanced materials characterization and materials modeling. This research further enhances the field through symposiums led by the investigators on the deformation mechanisms in ceramics.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.

非技术描述：过渡金属碳化物是一类具有广泛用途的陶瓷，包括切削材料、核能和涂层。这些应用使这些材料承受在使用中必须承受的温度和机械负载。该项目研究化学和晶体结构在控制负责这些特性的机械机制中的作用。通过该项目，研究生将接受培训以测试、表征、建模和预测过渡金属碳化物的机械行为。这些学生通常在社会的能源、国防和航空航天领域找到工作。此外，该项目还开发了中等教育学习模块，向中学生和高中生解释硬度这一技术定义。技术细节：众所周知，过渡金属碳化物具有独特的机械性能，这些性能与其化学和结构密切相关。该项目研究了这种化学反应，特别是碳原子的顺序，如何控制导致这些碳化物中特殊的异常硬化和低温蠕变的机械机制。实验和计算研究为阐明这些陶瓷中位错与温度、化学以及最重要的是非金属亚晶格的顺序相关的基本力学提供了协同支持。该项目首次使用序参数以化学序形式描述机械性能。鉴于这些材料在能源、航空航天和国防工业，特别是应用高超音速领域的重要性，该项目现在特别重要。此外，了解这种机械性能的机械联系将有助于开发新的成分复杂的过渡金属碳化物。鉴于研究的性质，研究生将接受两个互补领域（高级材料表征和材料建模）的综合培训。这项研究通过研究人员领导的关于陶瓷变形机制的研讨会进一步增强了该领域的发展。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力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 effects of mixing non-metal atoms in the B1 structured transition metal carbo-nitrides on their structure and mechanical properties: HfC1-N

B1结构过渡金属碳氮化物中混合非金属原子对其结构和力学性能的影响：HfC1-N

• DOI: 10.1016/j.oceram.2023.100356
• 发表时间: 2023-04-01
• 期刊: Open Ceramics
• 作者: Brennan R. Watkins;Jessica J. Lopez;Xiao;Gregory B. Thompson;C. Weinberger
• 通讯作者: C. Weinberger

Statistical study of vacancy diffusion in TiC and TaC

TiC和TaC中空位扩散的统计研究

• DOI: 10.1103/physrevmaterials.4.093602
• 发表时间: 2020-09-02
• 期刊: Physical Review Materials
• 影响因子: 3.4
• 作者: Xiaochuan Tang;Rofiques Salehin;G. Thompson;C. Weinberger
• 通讯作者: C. Weinberger

Vacancy-cluster and off-lattice metal-atom diffusion mechanisms in transition metal carbides

过渡金属碳化物中的空位团簇和晶格外金属原子扩散机制

• DOI: 10.1016/j.commatsci.2021.110713
• 发表时间: 2021-11
• 期刊: Computational Materials Science
• 影响因子: 3.3
• 作者: Salehin, Rofiques;Tang, Xiaochuan;Thompson, Gregory B.;Weinberger, Christopher R.
• 通讯作者: Weinberger, Christopher R.

The role of entropy and enthalpy in high entropy carbides

熵和焓在高熵碳化物中的作用

• DOI: 10.1016/j.commatsci.2022.111474
• 发表时间: 2022-07-01
• 期刊: Computational Materials Science
• 影响因子: 3.3
• 作者: Xiaochuan Tang;G. Thompson;Kaka Ma;C. Weinberger
• 通讯作者: C. Weinberger