权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Fundamental Investigations of Adiabatic Shear Localization in Materials with Mesoscale Heterogeneities

介观异质性材料中绝热剪切局域化的基础研究

基本信息

批准号：
1825582
负责人：
Pradeep Guduru
金额：
$ 44.14万
依托单位：
Brown University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-08-15 至 2022-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1825582&HistoricalAwards=false
关键词：
Fundamental Investigations Adiabatic Shear Localization

项目摘要

Progress in critical technologies is often enabled by advances in development of new materials, an important class of which is high-performance structural materials. The primary function of these materials is to withstand severe mechanical loads, often in harsh environments, with minimal weight. This award supports fundamental research to develop new and relatively unexplored materials in which the mesoscale structure of materials can be rationally designed to result in superior performance. The project will advance future materials design strategies for dynamic loading applications, examples of which include high speed impact of protective armor, explosive loading of structures, and high-speed machining, thereby advancing national health, prosperity, and welfare; and securing national defense. The fundamental materials design principles that will emerge from this research can be exploited by modern additive manufacturing technologies in manufacturing materials with rationally designed mesoscale architectures. In addition, the award supports educational activities for undergraduate students who will work in multidisciplinary teams to develop short educational animations and disseminate scientific discoveries in a manner accessible to middle and high school students. The award also supports development of educational modules for an outreach program at Brown University that serves students from underrepresented groups in science and technology. The research program focuses on understanding the role of mesoscale heterogeneities in the formation and propagation of adiabatic shear bands (ASB), which are an important mechanism by which materials and structures subjected to dynamic loading often fail catastrophically. The research aims to experimentally investigate the mechanics of how a propagating ASB interacts with a controlled heterogeneity through in situ high-speed microscopy, which is a new technique capable of high spatial (up to 0.7 micrometer) and temporal (250 nsec) resolutions simultaneously. When a propagating ASB encounters a heterogeneity of controlled geometry and properties, there are several possible outcomes: the ASB can get arrested, deflected or continue to propagate through and across the heterogeneity. Through in-situ measurement of the transient deformation fields during such interactions, the research seeks to determine the conditions under which each outcome prevails. Computational simulations of ASB-heterogeneity interactions will be carried out to interpret the experimental results, guide the experimental design with respect to the choice of material properties and geometry of the heterogeneities, and develop a predictive capability to help design more complex mesoscale architectures. The new fundamental knowledge gained from these studies can help develop novel mesoscale architectures with significantly enhanced resistance to ASB.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.

关键技术的进步往往是由新材料开发的进步促成的，其中一类重要的材料是高性能结构材料。这些材料的主要功能是承受严重的机械负荷，通常在恶劣的环境中，以最小的重量。该奖项支持基础研究，以开发新的和相对未开发的材料，其中材料的介观结构可以合理设计，从而产生上级性能。该项目将推进未来动态加载应用的材料设计策略，其中包括防护装甲的高速冲击，结构的爆炸加载和高速加工，从而促进国家健康，繁荣和福利;并确保国防。从这项研究中产生的基本材料设计原则可以通过现代增材制造技术来利用合理设计的中尺度结构制造材料。此外，该奖项还支持本科生的教育活动，他们将在多学科团队中工作，以初中和高中学生可以访问的方式开发简短的教育动画和传播科学发现。该奖项还支持布朗大学外展计划的教育模块开发，该计划为科学和技术领域代表性不足的群体的学生提供服务。该研究计划的重点是了解中尺度非均匀性在绝热剪切带（ASB）的形成和传播中的作用，这是一种重要的机制，通过这种机制，材料和结构受到动态载荷往往会发生灾难性的失败。该研究旨在通过原位高速显微镜实验研究传播ASB如何与受控异质性相互作用的机制，这是一种能够同时实现高空间（高达0.7微米）和时间（250纳秒）分辨率的新技术。当传播的ASB遇到受控几何形状和属性的异质性时，有几种可能的结果：ASB可以被阻止、偏转或继续传播通过和穿过异质性。通过在这种相互作用过程中的瞬态变形场的现场测量，该研究试图确定每个结果占上风的条件。ASB异质性相互作用的计算模拟将进行解释实验结果，指导实验设计方面的材料性能和几何形状的异质性的选择，并开发预测能力，以帮助设计更复杂的中尺度架构。从这些研究中获得的新的基础知识可以帮助开发新的中尺度结构，大大增强了对ASB的抵抗力。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。