DMREF/Collaborative Research: Multiscale Theory and Experiment in Search for and Synthesis of Novel Nanostructured Phases in BCN Systems

DMREF/合作研究：在 BCN 系统中寻找和合成新型纳米结构相的多尺度理论和实验

• 批准号: 1434613
• 负责人: Valery Levitas
• 金额: $ 33.33万
• 依托单位: Iowa State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-10-01 至 2018-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1434613&HistoricalAwards=false
• 关键词: DMREF; Collaborative; Research; Multiscale; Theory

Non-technical Description: Superhard materials, such as diamond, cubic boron nitride, and boron carbide (B4C) can exhibit high melting temperatures, large compression strengths, chemical inertness, and high thermal conductivity, making them of practical importance for science and engineering applications. However, they are brittle, breaking easily, a serious flaw that prevents many engineering applications. Computational approaches will be combined to develop ductile superhard materials for extended engineering applications. Initially, quantum mechanics will be used to predict the best candidates for new ductile superhard materials by analyzing a large number of cases in silico. For the best predicted materials novel experimental methods will be employed in which diamond anvil cells are twisted while applying high pressure to form the predicted phases. The properties of these materials will then be tested. Technical Description: The goal is to advance multiscale theory, modeling, and experiment sufficiently to enable a revolutionary new approach to search for and synthesize novel nanostructured phases in the BCN system. Large plastic shear deformation will be combined with high pressure in a unique rotational diamond anvil cell (RDAC), to (a) search for new nanostructured superhard phases that cannot be obtained under pressure without plastic shear straining, (b) dramatically reduce pressure required for phase transformation pathways to new and/or known phases, and (c) stabilize these new phases for processing at ambient pressure. The focus will be on some of the most promising materials within the BCN system: superhard phases of carbon (diamond, fullerene, high-density amorphous C, nanotubes, and long-range ordered amorphous clusters), boron, cubic cBN and wurtzitic wBN, cubic cBC2N, cBC4N, high density cC3N4 (predicted to be harder than diamond but never synthesized), nanostructured composites within BCN system, and other new phases in these systems, all of which will be predicted by the atomistic simulations.

非技术描述：钻石，立方体氮化物和碳化物（B4C）等超智材料可以表现出高熔融温度，较大的压缩强度，化学惰性和高导热性，从而使它们对科学和工程应用具有实际重要性。但是，它们很脆，很容易破裂，这是一个严重的缺陷，可防止许多工程应用。计算方法将结合使用，以开发用于扩展工程应用的延性超胸材料。最初，量子力学将用于通过分析硅中的大量病例来预测新的延性超胸材料的最佳候选物。对于最佳预测材料，将采用新型实验方法，其中钻石砧细胞在施加高压时扭曲了预测相。然后将测试这些材料的特性。技术描述：目标是充分进步多尺度理论，建模和实验，以使革命性的新方法在BCN系统中搜索和合成新颖的纳米结构阶段。在独特的旋转钻石砧（RDAC）中，大型塑料剪切变形将与高压结合在一起，以（a）寻找在没有塑料剪切扭伤的情况下在压力下无法获得的新纳米结构的超智相，（b）大大降低了对新的和/或已知的阶段和（c）稳定的稳压所需的压力所需的压力。重点将放在BCN系统中的一些最有前途的材料上：碳的超智阶段（钻石，富勒烯，高密度的无形C，纳米管和远程有序的无定形簇），硼，立方CBN和wurtzitic cbn和wurtzitic wbn，wurtzitic wbn，Cubc2n，Cubc2n，CBC2N，CBC2N，CBC4N，高度cc3，高度cc3，高度cc3，cc3 cc3，ccc cc3 cc3 cc3 and ccc cc3 cc3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc c c c c c c的合成的），BCN系统中的纳米结构复合材料以及这些系统中的其他新阶段，所有这些阶段将由原子模拟预测。

项目成果

Large elastoplastic deformation of a sample under compression and torsion in a rotational diamond anvil cell under megabar pressures

• DOI: 10.1016/j.ijplas.2017.03.002
• 发表时间: 2017-05
• 期刊: International Journal of Plasticity
• 影响因子: 9.8
• 作者: B. Feng;V. Levitas

Coupled elastoplasticity and plastic strain-induced phase transformation under high pressure and large strains: Formulation and application to BN sample compressed in a diamond anvil cell

• DOI: 10.1016/j.ijplas.2017.05.002
• 发表时间: 2017-09-01
• 期刊: INTERNATIONAL JOURNAL OF PLASTICITY
• 影响因子: 9.8
• 作者: Feng, Biao;Levitas, Valery I.
• 通讯作者: Levitas, Valery I.

FEM simulation of large deformation of copper in the quasi-constrain high-pressure-torsion setup

• DOI: 10.1016/j.msea.2017.08.078
• 发表时间: 2017-09-29
• 期刊: MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
• 影响因子: 6.4
• 作者: Kamrani, Mehdi;Levitas, Valery I.;Feng, Biao
• 通讯作者: Feng, Biao

Plastic flows and strain-induced alpha to omega phase transformation in zirconium during compression in a diamond anvil cell: Finite element simulations

• DOI: 10.1016/j.msea.2016.10.082
• 发表时间: 2017-01-05
• 期刊: MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
• 影响因子: 6.4
• 作者: Feng, Biao;Levitas, Valery I.
• 通讯作者: Levitas, Valery I.