GOALI: Phase Transforming Cellular Materials

我们对微结构材料力学的理解的快速增长，加上在一定长度范围内制造这种材料的能力的相应增加，导致了新一代材料具有独特的特性组合，这些特性是传统材料难以获得的。该研究项目将探索蜂窝材料相变的新概念，这可能会影响关键行业和应用领域，从具有综合能量吸收，能量收集和波束能力的结构到自适应催化剂基底和具有可切换润湿性和致动特性的材料。在基础材料研究阶段与汽车制造商的密切合作确保了工作与行业需求保持相关。本科生和研究生的教育和培训将是该项目的一个组成部分，由于该项目的跨学科性质，参与该项目的学生将接触到这些材料的分析，合成和测试的各个方面。从这项研究计划中学到的信息将在国际会议上传播，在期刊出版物，并直接带入课堂。此外，PI将与普渡大学的少数民族工程计划（MEP）合作，为当地博物馆开展社区外展活动。本研究的目标是促进对一组新的相变细胞材料（PXCM）的理解，其构建块在暴露于驱动相变的适当刺激时可以发生大的双稳态或亚稳态构象变化。由于这种相变，多孔材料的有效性质在其稳定相之间是不同的。此外，相变过程本身导致能量的显著耗散，而不会在基材中引起永久的非弹性变形。这两个方面都让人想起热力学系统中的一级相变。该研究计划将（a）研究准静态载荷下PXCM中应力诱导相变的正向和反向动力学，（B）和动态载荷下，（c）研究PXCM中温度诱导相变的正向和反向动力学，（d）有系统地探讨电力XCM的设计空间，以及研究波传播特性的变化伴随相变使用的方法，结合分析和数值模拟与实验在多个长度尺度。特别强调将可逆的固态能量耗散能力集成到结构构件中。

Rapid growth in our understanding of the mechanics of micro-architectured materials complemented by a corresponding increase in the ability to manufacture such materials over a range of length scales has led to a new generation of materials with unique combinations of properties that are otherwise difficult to obtain with traditional materials. This Grant Opportunity for Academic Liaison with Industry (GOALI) research project will explore a new concept of phase transformation in cellular materials that could impact key industries and application areas ranging from structures with integrated energy absorption, energy harvesting and wave beaming capabilities to adaptive catalyst substrates and materials with switchable wettability and actuation properties. A close collaboration with an automotive manufacturer at the fundamental materials research stage ensures that the work remains relevant to industry needs. Education and training for undergraduate and graduate students will be an integral part of this project, and due to the interdisciplinary nature of the project, students involved in it will be exposed to diverse aspects of the analysis, synthesis and testing of these materials. Information learned from this research program will be disseminated at international conferences, in journal publications and brought directly into the classroom. Additionally, the PI will work with the Minority Engineering Program (MEP) at Purdue University to develop community outreach activities for local museums.The goal of this research is to advance the understanding of a novel set of phase transforming cellular materials (PXCMs) whose building blocks can undergo large bi- or meta-stable conformational changes when exposed to an appropriate stimulus that drives the phase transformation. As a result of this phase transformation, the effective properties of the cellular material are different between its stable phases. Moreover, the phase transformation process itself results in significant dissipation of energy without inducing permanent inelastic deformation in the base material. Both of these aspects are reminiscent of first-order phase transformations in thermodynamic systems. This research program will (a) study the kinetics of the forward and reverse stress-induced phase transformations in PXCMs under quasi-static loading, (b) and under dynamic loading, (c) study the kinetics of the forward and reverse temperature-induced phase transformations in PXCMs, (d) carry out a systematic exploration of the design space for PXCMs and (e) study the changes in wave propagation properties accompanying phase transformations using an approach that combines analytical and numerical modeling with experiments at multiple length scales. Special emphasis will be placed on the integration of reversible, solid-state energy dissipation capability into structural members.