Identifying the origin of hardness in AlMgB14 and the orthorhombic boron-rich borides

该奖项支持旨在研究以AlMgB14晶体为代表的正交硼化物的化学键合的理论和计算研究和教育。AlMgB14是最近发现的具有成为有效超硬材料潜力的晶体家族的成员。然而，它们相对开放的结构和灵活的化学组成使得实验观察到的硬度令人惊讶。 在原子水平上，人们还没有全面了解为什么这种晶体家族如此坚硬，或者如何控制它们的物理性质。该奖项所支持的研究重点是提供这种全面的理解。PI将研究AlMgB14晶体的静态和动态响应，以阐明其基本力学性能的起源。将研究杂质原子对晶格位置的替代，以了解化学替代对机械性能的影响。杂质原子的结构和能量将被表征。PI的计算结果将与他在艾姆斯实验室和田纳西大学的合作者进行的实验研究进行比较。拟议的研究不仅有助于阐明这些材料的理想物理特性的原子机制，而且还允许对这些特性进行定制。这项工作可能会导致开发出一种新的、可设计的超硬材料，这种材料可能会有重要的工程应用。由于创造新的超硬材料的经济和环境重要性，该项目的成功完成预计将对社会产生持久的积极影响。迫切需要新的硬和超硬材料，可用于提高机床寿命，磨削介质和耐磨涂层。改进制造工艺将同时减少制造对环境的影响，并节省经济成本。即使是效率的微小提高也会带来全球都能感受到的巨大社会效益。超硬材料具有降低能源消耗和延长工具寿命的潜力，自然是一项有吸引力的技术。PI致力于通过积极指导研究生，本科生和高中生来培养下一代科学家和工程师。为了促进计算科学在中学水平的领域，PI将开发在奥马哈，东北大都会区的高中生每年周六研讨会。通过向学生介绍自然科学的丰富，现实世界的复杂性，并展示如何使用计算机来解决这些问题，学生将接触到这些学科的更广泛的背景。这将自然地增加计算机科学和自然科学的吸引力。非技术概述该奖项支持理论和计算研究和教育，旨在研究最近发现的一类材料中的化学键，以AlMgB 14晶体为代表。这些材料由于其高强度、化学惰性和成分灵活性而具有成为有效超硬材料的潜力。然而，在原子水平上，人们还没有全面了解为什么这种晶体家族如此坚硬，或者如何控制它们的物理性质。该奖项所支持的研究重点是提供这种全面的理解。PI将研究AlMgB14晶体的静态和动态特性，以阐明其机械性能的基本来源。在一些计算研究中，将各种杂质原子添加到主体晶体中的特定位置，以了解这种添加是否在能量上有利，如果是这样，它们是否会对材料的机械性能产生理想的影响。PI的计算结果将与他在艾姆斯实验室和田纳西大学的合作者进行的实验研究进行比较。这项研究不仅有助于阐明这些材料所观察到的物理特性的原子机制，而且还可以定制这些特性。这项工作可能会导致开发出一种新的、可设计的超硬材料，这种材料可能会有重要的工程应用。由于创造新的超硬材料的经济和环境重要性，该项目的成功完成预计将对社会产生持久的积极影响。迫切需要新的硬和超硬材料，可用于提高机床寿命，磨削介质和耐磨涂层。改进制造工艺将同时减少制造对环境的影响，并节省经济成本。即使是效率的微小提高也会带来全球都能感受到的巨大社会效益。超硬材料具有降低能源消耗和延长工具寿命的潜力，自然是一项有吸引力的技术。PI致力于通过积极指导研究生，本科生和高中生来培养下一代科学家和工程师。为了促进计算科学在中学水平的领域，PI将开发在奥马哈，东北大都会区的高中生每年周六研讨会。通过向学生介绍自然科学的丰富，现实世界的复杂性，并展示如何使用计算机来解决这些问题，学生将接触到这些学科的更广泛的背景。这自然会增加计算机科学和自然科学的吸引力。

TECHNICAL SUMMARYThis award supports theoretical and computational research and education aimed at studying the chemical bonding of orthorhombic borides, typified by the AlMgB14 crystal. The AlMgB14 is a member of a recently discovered family of crystals that have the potential to be effective superhard materials. However, their relatively open structure and flexible chemical composition make the experimentally observed hardness surprising. At the atomic level, there is no comprehensive understanding of why this crystal family is so hard or how their physical properties can be controlled. The research supported by this award is focused on providing such comprehensive understanding.The PI will investigate both the static and dynamical response of AlMgB14 crystals to elucidate the origin of their mechanical properties at a fundamental level. The substitution of impurity atoms to the lattice sites will be studied to understand the impact of chemical substitution on the mechanical properties. The structure and energy of the impurity atoms will be characterized. The results from PI's computations will be compared to experimental investigations performed by his collaborators at Ames Laboratory and at the University of Tennessee. The proposed research will not only help elucidate the atomistic mechanisms responsible for the desirable physical properties of these materials, but also allow for such properties to be tailored. This effort could potentially lead to the development of a new, designable class of superhard materials that will likely have significant engineering applications.The successful completion of this project is expected to have a lasting positive impact on society because of the economic and environmental importance of creating new superhard materials. There is an imminent need for new hard and superhard materials that can be used to improve machine tool lifetime, grinding medium, and wear-resistant coatings. Improving manufacturing processes will simultaneously reduce the environmental impact of manufacturing and produce economic cost-savings. Even modest improvements in efficiency will result in substantial social benefits that will be felt globally. Superhard materials, which have the potential to reduce energy consumption and increase the lifetime of tools, are naturally an attractive technology.The PI is committed to preparing the next generation of scientists and engineers by actively mentoring graduate, undergraduate, and high school students. To promote the field of Computational Science at a secondary school level, the PI will develop an annual Saturday workshop for high school students in the Omaha, NE metro area. By introducing the students to the rich, real-world complexities of the natural sciences and showing how computers are used to address them, the students will be exposed to the broader context of these disciplines. This will naturally increase the appeal of both computer science and the natural sciences.NON-TECHNICAL SUMMARY This award supports theoretical and computational research and education aimed at studying the chemical bonding in a recently discovered class of materials, typified by the AlMgB14 crystal. These materials have the potential to be effective superhard materials due to their high strength, chemical inertness and compositional flexibility. However, at the atomic level, there is no comprehensive understanding of why this crystal family is so hard or how their physical properties can be controlled. The research supported by this award is focused on providing such comprehensive understanding.The PI will investigate both the static and dynamical properties of AlMgB14 crystals to elucidate the origin of their mechanical properties at a fundamental level. In several computational studies, various impurity atoms will be added to specific positions in the host crystal to understand whether such additions are energetically favorable, and if so, whether they could have desirable impact on the material's mechanical properties. The results from PI's computations will be compared to experimental investigations performed by his collaborators at Ames Laboratory and at the University of Tennessee. The research will not only help elucidate the atomistic mechanisms responsible for the observed physical properties of these materials, but also allow for such properties to be tailored. This effort could potentially lead to the development of a new, designable class of superhard materials that will likely have significant engineering applications.The successful completion of this project is expected to have a lasting positive impact on society because of the economic and environmental importance of creating new superhard materials. There is an imminent need for new hard and superhard materials that can be used to improve machine tool lifetime, grinding medium, and wear-resistant coatings. Improving manufacturing processes will simultaneously reduce the environmental impact of manufacturing and produce economic cost-savings. Even modest improvements in efficiency will result in substantial social benefits that will be felt globally. Superhard materials, which have the potential to reduce energy consumption and increase the lifetime of tools, are naturally an attractive technology.The PI is committed to preparing the next generation of scientists and engineers by actively mentoring graduate, undergraduate, and high school students. To promote the field of Computational Science at a secondary school level, the PI will develop an annual Saturday workshop for high school students in the Omaha, NE metro area. By introducing the students to the rich, real-world complexities of the natural sciences and showing how computers are used to address them, the students will be exposed to the broader context of these disciplines. This will naturally increase the appeal of both computer science and the natural sciences.