Collaborative Research: Design of Low-Hysteresis High-Susceptibility Materials by Nanodomain Engineering

合作研究：利用纳米域工程设计低磁滞高磁化率材料

• 批准号: 1410636
• 负责人: Ju Li
• 金额: $ 30万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2017-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1410636&HistoricalAwards=false
• 关键词: Collaborative; Research; Design; Low; Hysteresis

NONTECHICAL SUMMARYThis award supports theoretical and computational research aimed to develop new design concepts and principles for shape memory alloys, and ferroelectric and ferromagnetic materials to achieve improved functionality for various applications. In these materials structural domains can switch from one to another by the application of an external field, such as stress, electric or magnetic fields, allowing sensing and actuation to be realized simultaneously. These smart materials have found critical applications in many fields, including medical devices, satellites, robots, navigation systems, data storage and retrieving, electromechanical and electro-optic systems, to name a few. However, typical domain structures formed in these materials are too large leading to properties that are not optimal for applications. Another common problem is that functional fatigue that leads to premature failure. The PIs will use advanced computational and theoretical methods to investigate new design concepts and principles that connect crystal structure, defects, domain structure and functional properties. These design concepts and principles are aimed to guide experimental efforts and accelerate the discovery of new smart as well as structural materials with optimal properties. This is in alignment with the Materials Genome Initiative. This project will directly prepare graduate students to immediately contribute to the success of integrated computational materials science and engineering. Additionally, the training of researchers involved in materials development will afford a rapid uptake of new design concepts and methodology, resulting in increased effectiveness of materials technologists. The educational outreach of the project is designed to have a significant influence on encouraging high school students who are members of underrepresented groups to enter science and engineering disciplines.TECHNICAL SUMMARYThis award supports theoretical and computational research that focuses on ferroic-based functional materials including shape memory alloys, and ferroelectric and ferromagnetic materials. The main objective of this project is to accelerate the discovery of novel low-hysteresis high-susceptibility ferroic-based functional materials with strong fatigue resistance via the design of (a) transformation pathway networks, and (b) structural and chemical heterogeneities. The former explores the means to achieve high susceptibility by identifying systems with isolated circular transformation pathways, while the latter explores how to transform conventional micron-sized, long-range ordered, self-accommodating strain, polarization and magnetization domains into nanodomains by suppressing autocatalysis and regulating the spatial extent of domain growth and coarsening during ferroic phase transitions. A rigorous theoretical framework will be developed based on group theory, phase transformation crystallography and graph methods to analyze transformation pathway networks (TPNs). Through investigating the symmetry and topology of TPN graphs, a new classification of structural phase transformations will be introduced. The PIs aim to distinguish three distinct TPN types: ones that could provide high susceptibility, ones that are reversible and exhibit shape memory effect, and ones that could generate dislocations through transformations causing functional fatigue. The PI will perform systematic first principles and atomistic calculations for specific systems to assist in constructing and classifying TPN graphs, to quantify the energy landscapes, and to investigate the effects of various crystalline defects. Finally phase field simulations will be carried out to examine possible continuous phase separations and other mechanisms to generate nanoscale structural and chemical non-uniformities in the parent phase and to study their effects on subsequent ferroic phase transitions and ferroic nanodomain formation. The responses of these ferroic nanodomains to temperature and external fields will be documented. Drastically different properties from those of their microdomain counterparts are expected, in particular ultra-low-modulus quasi-linear pseudoelasticity, low hysteresis, high susceptibility such as giant piezoelectricity, giant magnetostriction and giant non-hysteretic strain response, and strong fatigue resistance. The educational outreach of the project is designed to have a significant influence on encouraging high school students who are members of underrepresented groups to enter science and engineering disciplines.

非技术摘要该奖项支持理论和计算研究，旨在开发形状记忆合金、铁电和铁磁材料的新设计概念和原理，以实现各种应用的改进功能。在这些材料中，结构域可以通过施加外部场（例如应力、电场或磁场）从一种结构域切换到另一种结构域，从而可以同时实现传感和驱动。这些智能材料在许多领域都有重要应用，包括医疗设备、卫星、机器人、导航系统、数据存储和检索、机电和光电系统等。然而，这些材料中形成的典型域结构太大，导致性能对于应用而言不是最佳的。另一个常见问题是功能性疲劳导致过早衰竭。 PI 将使用先进的计算和理论方法来研究连接晶体结构、缺陷、域结构和功能特性的新设计概念和原理。这些设计概念和原则旨在指导实验工作并加速发现具有最佳性能的新型智能和结构材料。这与材料基因组计划是一致的。该项目将直接帮助研究生做好准备，立即为综合计算材料科学与工程的成功做出贡献。此外，参与材料开发的研究人员的培训将有助于快速采用新的设计概念和方法，从而提高材料技术人员的效率。该项目的教育推广旨在对鼓励弱势群体的高中生进入科学和工程学科产生重大影响。技术摘要该奖项支持专注于包括形状记忆在内的铁基功能材料的理论和计算研究合金、铁电和铁磁材料。该项目的主要目标是通过（a）转变路径网络和（b）结构和化学异质性的设计，加速发现具有强抗疲劳性的新型低磁滞高磁化率铁基功能材料。前者探索通过识别具有孤立的圆形转化途径的系统来实现高磁化率的方法，而后者则探索如何通过抑制自催化和自调节将传统的微米级、长程有序、自调节应变、极化和磁化域转化为纳米域。调节铁相变过程中磁域生长和粗化的空间范围。将基于群论、相变晶体学和图方法开发严格的理论框架来分析转化途径网络（TPN）。通过研究 TPN 图的对称性和拓扑，将引入结构相变的新分类。 PI 旨在区分三种不同的 TPN 类型：可提供高敏感性的类型、可逆且表现出形状记忆效应的类型以及可通过导致功能疲劳的转变产生位错的类型。 PI将为特定系统执行系统的第一原理和原子计算，以协助构建和分类TPN图，量化能量景观，并研究各种晶体缺陷的影响。最后，将进行相场模拟，以检查可能的连续相分离和其他机制，以在母相中产生纳米级结构和化学不均匀性，并研究它们对随后的铁性相变和铁性纳米域形成的影响。这些铁纳米域对温度和外部场的响应将被记录下来。预计其性能将与微域对应物截然不同，特别是超低模量准线性赝弹性、低磁滞、高磁化率（如巨压电、巨磁致伸缩和巨非磁滞应变响应）以及强抗疲劳性。该项目的教育推广旨在对鼓励弱势群体的高中生进入科学和工程学科产生重大影响。