Shear Strength and Phase Transformations in Transition Metals and their Diborides under Terapascal Pressures

兆帕压力下过渡金属及其二硼化物的剪切强度和相变

• 批准号: 1904164
• 负责人: Yogesh Vohra
• 金额: $ 38.26万
• 依托单位: University of Alabama at Birmingham
• 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 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1904164&HistoricalAwards=false
• 关键词: Shear; Strength; Phase; Transformations; Transition

PART 1: NON-TECHNICALThe transition metals (such as iron, manganese, copper and lesser known elements rhenium and osmium) and their alloys are widely used in aerospace, biomedical, and nuclear industries while transition metal diborides (one atom transition metal and 2 atoms of boron) have potential applications as high-strength structural materials under extreme conditions of stress, temperature, and corrosive environments. The application of high pressure on transition metals and their diborides is expected to yield novel structural modifications with desirable mechanical properties. The phase transformation studies and shear strength measurements on materials under high-pressures will be carried out using an innovative diamond anvil technology coupled to an x-ray synchrotron source. The computational calculations will use the state-of-the-art supercomputing facilities to predict stable crystal structures and their elastic properties and shear strength. This study will map out the crystalline phases and their shear strength with varying pressure with a goal of novel material synthesis that can be retained at ambient conditions for industrial applications. The project participants will receive extensive research and curriculum training in computational materials research and at the premier national facilities employing x-ray synchrotron radiation leading to a pipeline of trained scientific workforce in academia, national laboratories and industry. University of Alabama at Birmingham in partnership with the Historically Black Colleges and Universities in the southeastern region will jointly undertake efforts in broadening participation of underrepresented groups at all levels in the science and engineering fields.PART 2: TECHNICAL The study of phase transformations and shear strength measurements under high-pressures not only provides key-insights into mechanical properties under pressure but also provides a pathway to synthesizing novel materials under extreme conditions. The study of materials under extreme conditions has seen rapid progress recently with the attainment of near Terapascal (1 TPa = 1000 GPa) static pressures using toroidal single crystal diamond anvils and by employing two-stage nanocrystalline diamond micro-anvils. In addition, density functional theory has been applied to compute stable crystal structures and their elastic constants at high pressure for direct comparison with the experimental data on elastic moduli and shear strength under ultrahigh pressures. University of Alabama at Birmingham will perform phase transformations and shear strength measurements on rhenium (Re), osmium (Os), and their diborides ReB2 and OsB2 under both hydrostatic (helium pressure medium) and non-hydrostatic (no pressure medium) conditions. The ReB2 and OsB2 have high hardness values at ambient conditions in the range of 22-37 GPa and their shear strength variation with pressure is of considerable interest. The TPa pressure range is expected to cause significant electron transfer within the conduction band and possibly cause core-overlap leading to novel structural modifications with desirable mechanical properties. This study would provide crystal structure data and shear strength data for this unique electronic state of transition metals and their diborides under extreme conditions for direct comparison with the density functional calculations.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.

第1部分：非技术的过渡金属（例如铁，锰，铜和鲜为人知的元素rhenium and Osmium）及其合金在航空航天，生物医学和核工业中广泛使用，而过渡金属二键型（一种原子过渡金属和2个原子的过渡金属和2个原子）具有高度较高的结构材料，并具有较高的条件。高压在过渡金属及其二吡啶的应用有望产生具有理想的机械性能的新结构修饰。在高压下，将使用与X射线同步器源耦合的创新钻石砧技术对材料进行的相变研究和剪切强度测量。计算计算将使用最先进的超级计算设施来预测稳定的晶体结构及其弹性特性和剪切强度。这项研究将以不同的压力来绘制结晶相及其剪切强度，其目标是新型材料合成的目标，可以在工业应用的环境条件下保留。该项目参与者将在计算材料研究中以及采用X射线同步辐射的主要国家设施中接受广泛的研究和课程培训，从而导致学术界，国家实验室和工业的训练有素的科学劳动力管道。阿拉巴马大学与历史上历史悠久的黑人学院和东南地区的大学合作，将共同努力在科学和工程领域的各个级别的各个级别的各个级别的参与范围内共同努力。第2部分：技术研究的技术研究研究，对高压下的剪切强度测量不仅为材料提供了强度的构图，还为构成了强大的构图，从而提供了构造的概念，以构成构成的概念。在极端条件下对材料的研究最近在使用环形单晶钻石铁链以及使用两阶段的纳米晶型钻石微型分子的情况下实现了接近Terapascal（1 TPA = 1000 GPA）静态压力的迅速发展。此外，密度功能理论已应用于计算稳定的晶体结构及其在高压下的弹性常数，以直接比较弹性模量和超高压下的弹性模量和剪切强度的实验数据。阿拉巴马大学伯明翰大学将在Hydystatic（氦气培养基）和非溶剂凝聚力（无压力培养基）条件下对Rhenium（RE），Osmium（OS）及其二曲霉Reb2和OSB2进行相变和剪切强度测量。 REB2和OSB2在22-37 GPA范围内的环境条件下具有较高的硬度值，其剪切强度随压力的变化引起了人们的关注。预计TPA压力范围会在传统带中引起显着的电子转移，并可能引起核心重叠，从而导致具有理想的机械性能的新型结构修饰。这项研究将为这种独特的过渡金属的电子状态提供晶体结构数据和剪切强度数据，并在极端条件下与密度功能计算直接比较，以与NSF的法定任务进行直接比较。

项目成果

Experimental and theoretical P-V-T equation of state for Os 2 B 3

Os 2 B 3 的实验和理论 P-V-T 状态方程

• DOI: 10.1080/08957959.2020.1858821
• 发表时间: 2020
• 期刊: High Pressure Research
• 影响因子: 2
• 作者: Burrage, Kaleb C.;Lin, Chia-Min;Chen, Wei-Chih;Chen, Cheng-Chien;Vohra, Yogesh K.
• 通讯作者: Vohra, Yogesh K.

Experimental and Computational Studies on Superhard Material Rhenium Diboride under Ultrahigh Pressures

• DOI: 10.3390/ma13071657
• 发表时间: 2020-04-01
• 期刊: MATERIALS
• 影响因子: 3.4
• 作者: Burrage, Kaleb C.;Lin, Chia-Min;Vohra, Yogesh K.
• 通讯作者: Vohra, Yogesh K.

Shear strength measurements and hydrostatic compression of rhenium diboride under high pressures

• DOI: 10.1063/5.0050057
• 发表时间: 2021-05-28
• 期刊: JOURNAL OF APPLIED PHYSICS
• 影响因子: 3.2
• 作者: Burrage, Kaleb C.;Park, Changyong;Vohra, Yogesh K.
• 通讯作者: Vohra, Yogesh K.

Theoretical and experimental studies of compression and shear deformation behavior of Osmium to 280 GPa

280 GPa 锇压缩和剪切变形行为的理论和实验研究

• DOI: 10.1088/2631-8695/ac34c4
• 发表时间: 2021
• 期刊: Engineering Research Express
• 影响因子: 1.7
• 作者: Lin, Chia Min;Burrage, Kaleb C;Perreault, Chris;Chen, Wei-Chih;Chen, Cheng-Chien;Vohra, Yogesh K
• 通讯作者: Vohra, Yogesh K