Fundamental Study of Low-Cycle-Fatigue Behavior of High-Entropy Alloys

高熵合金低周疲劳行为的基础研究

• 批准号: 1611180
• 负责人: Peter Liaw
• 金额: $ 42万
• 依托单位: University of Tennessee Knoxville
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1611180&HistoricalAwards=false
• 关键词: Fundamental; Study; Low; Cycle; Fatigue

Non-Technical AbstractThis project will study low-cycle-fatigue behavior of a new class of multi-component alloys called high-entropy alloys. These alloys have attracted huge attention in recent five years for their unique mechanical properties. The transformative potential of the present work is represented as a systematic and innovative investigation for structural characterization experiments, thus revealing the deformation mechanisms under cyclic loading and integrating the design, fabrication, verification, improvement, and prediction components, which can be applied for the studies of other advanced materials in the future. Students and researchers involved in this project will have opportunities to experience the state-of-the-art research equipment at the national laboratories. The outreach activities will include the K-12 science education, minority involvement, and efforts to engage the public. The results of the project will be disseminated through avenues accessible to the scientific community and to the general public with an emphasis on middle- and high-school students, as well as women and minority students. Appropriate aspects of the research results will be incorporated into the principal investigator's (PI's) graduate and undergraduate course materials to introduce students to modern interdisciplinary materials research. Technical AbstractThe goal of this project is to (1) study the low-cycle fatigue (LCF) behavior of high-entropy alloys (HEAs) by varying the structures (e.g., controlling the Al content), (2) clarify the deformation mechanisms of HEAs during LCF using state-of-art characterization methods (e.g., advanced microscopy and in-situ neutron diffraction), and (3) based on the fundamental understanding of the deformation behavior obtained from the present work, design and develop innovative HEAs with excellent LCF properties. HEAs attract huge attention in recent five years for their unique and excellent mechanical properties. Even though extensive studies have been devoted to the mechanical behavior,most of these research activities are for monotonic tests and almost none has focused on the fatigue properties, especially LCF. The mechanism of fatigue behavior must be examined carefully before HEAs can indeed be introduced in practical applications. The critical issues, thus, become obvious: (1) how do the multi-principal elements affect structures, and further, fatigue properties; (2) how does the high-entropy configuration influence the deformation mechanism; and (3) if the above two aspects have positive effects on the fatigue resistance, what are the fundamental contributing factors. Accordingly, a hypothesis is proposed and to be tested in the present work that HEAs with some specific compositions (i.e., structures) will show superior fatigue resistance over traditional alloys due to (1) great tendency to form twins, (2) solute atoms and large distortion from the element-size mismatch to pin dislocations, and (3) the interaction between dislocation and twinning, before fatigue-crack initiation and during crack propagation at room and elevated temperatures, and their long-term performance can be modulated and further improved by cold or hot treatment (e.g., cold rolling to control grain size). It is expected that the mechanism of LCF behavior could be revealed by a combination of the proposed experimental, theoretical, and modeling efforts, thus providing the fundamental understanding of the deformation behavior for single- and multiple-phase HEAs.

非技术抽象的项目将研究一种称为高渗透合金的新型多组分合金的低周期效果行为。这些合金在最近五年中引起了极大的关注，因为它们的独特机械性能。本工作的变革潜力表示为结构表征实验的系统和创新研究，从而揭示了环状负载下的变形机制，并整合了设计，制造，验证，改进和预测组件，可以将来应用于未来其他先进材料的研究。 参与该项目的学生和研究人员将有机会体验国家实验室的最先进的研究设备。外展活动将包括K-12科学教育，少数派参与以及参与公众的努力。该项目的结果将通过科学界和公众访问的途径以及强调中学和高中生以及妇女和少数族裔学生的途径来传播。研究结果的适当方面将纳入主要研究者（PI）的研究生和本科课程材料中，以向学生介绍现代跨学科材料研究。 技术摘要该项目的目的是（1）研究高渗透合金（LCF）通过改变结构（例如，控制Al含量）的高且高复制合金（HEAS）的行为；了解从当前工作中获得的变形行为，设计和开发具有出色LCF特性的创新HEAS。 HEAS最近五年引起了极大的关注，因为它们的独特和出色的机械性能。即使广泛的研究已致力于机械行为，但这些研究活动中的大多数都是用于单调测试，几乎没有一个专注于疲劳性能，尤其是LCF。必须在实际应用中引入HEAS之前仔细检查疲劳行为的机制。因此，关键问题变得显而易见：（1）多主体要素如何影响结构，进一步影响疲劳特性； （2）高渗透构型如何影响变形机制； （3）如果以上两个方面对疲劳抗性具有积极影响，那么基本的促成因素是什么。因此，提出了假设并在目前的工作中进行测试，即具有某些特定组成（即结构）的HEAS将显示出比（1）形成双胞胎的巨大趋势相比，（2）在（2）与销量的较大型和（3）互动之间的互动和（3）提出的相互作用和（3）提出的较大的扭曲和（3），并且（3）在（3）中的较大扭曲和（3），并且（3）在（3）中提出了（3），并且（3）在（3）中提出了（3）房间和升高的温度及其长期性能可以调节，并通过冷或热处理进一步改善（例如，冷滚动以控制晶粒尺寸）。可以预期，LCF行为的机制可以通过提出的实验，理论和建模工作的组合来揭示，从而提供了对单相和多相HEAS变形行为的基本理解。

项目成果

Novel NiAl-strengthened high entropy alloys with balanced tensile strength and ductility

• DOI: 10.1016/j.msea.2018.11.055
• 发表时间: 2019-01
• 期刊: Materials Science and Engineering: A
• 作者: H. Diao;D. Ma;R. Feng;Tingkun Liu;Chao Pu;Chuan Zhang;W. Guo;J. Poplawsky;Yanfei Gao

Effects of nitrogen content on microstructures and mechanical properties of (AlCrTiZrHf)N high-entropy alloy nitride films

• DOI: 10.1016/j.jallcom.2020.155063
• 发表时间: 2020-09-05
• 期刊: JOURNAL OF ALLOYS AND COMPOUNDS
• 影响因子: 6.2
• 作者: Cui, Panpan;Li, Wei;Liaw, Peter K.
• 通讯作者: Liaw, Peter K.

Microstructure and tribological behavior of in situ synthesized (TiB+TiC)/Ti6Al4V (TiB/TiC=1/1) composites

原位合成(TiB TiC)/Ti6Al4V (TiB/TiC=1/1)复合材料的微观结构和摩擦学行为

• DOI: 10.1016/j.triboint.2020.106177
• 发表时间: 2020-05
• 期刊: Tribology International
• 影响因子: 6.2
• 作者: Zheng Bowen;Dong Fuyu;Yuan Xiaoguang;Huang Hongjun;Zhang Yue;Zuo Xiaojiao;Luo Liangshun;Wang Liang;Su Yanqing;Li Weidong;Liaw Peter K.;Wang Xuan
• 通讯作者: Wang Xuan

Effects of Constituent Elements and Fabrication Methods on Mechanical Behavior of High-Entropy Alloys: A Review

• DOI: 10.1007/s11661-018-4970-z
• 发表时间: 2019-01-01
• 期刊: METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
• 影响因子: 2.8
• 作者: Lyu, Zongyang;Lee, Chanho;Liaw, Peter K.
• 通讯作者: Liaw, Peter K.

The elastic-strain energy criterion of phase formation for complex concentrated alloys

• DOI: 10.1016/j.mtla.2019.100222
• 发表时间: 2019-03-01
• 期刊: MATERIALIA
• 影响因子: 3.4
• 作者: Andreoli, Angelo F.;Orava, Jiri;Kaban, Ivan
• 通讯作者: Kaban, Ivan