CAREER: Mechanics of a New Family of Auxetic Chiral Composites

这个教师早期职业发展（CAREER）项目将研究一个新的拉胀手性复合材料家族的机械行为，该复合材料具有独特的变形机制，可以在大变形下保持拉胀效应。基于分析力学模型，将发明一种新的拉胀手性复合材料，并通过有限元模拟，微极理论和多材料3D打印试样的力学实验来探索其变形机制。同时，由于显着的局部旋转，这些新的微结构材料提供了很好的例子，在微极理论的应用，并将用于推进这一重要的理论在力学。增材制造（3D打印）的快速发展使微结构混合材料的几何形状和材料成分能够轻松精确地控制，为推动力学边界提供了前所未有的机会。这项研究揭示了一种使用3D打印作为工具来推进现有力学理论和验证新工程概念的范例。这一新的拉胀手性复合材料家族的力学新知识的创造预计将在设计用于机械保护和能量吸收的轻质材料、改善公共健康的生物医学材料和设备、以及超材料和机械自适应复合材料。推广和参与活动旨在与教育活动相结合，并将主要集中在参与和保留代表性不足的群体，通过将看似传统的机械工程概念与创新的跨学科概念相结合。 这将通过以下方式实现：（1）让所有不同层次的参与者参与，从研究生和本科生，小学和中学的学生和教师到实践工程师，（2）加强力学，仿生学和增材制造学科内和跨学科的课程，（3）与当地，小/中型规模，（4）发展中小学外展活动，以支持新发布的下一代科学标准。

This Faculty Early Career Development (CAREER) project will investigate the mechanical behavior of a new family of auxetic chiral composites which have unique deformation mechanisms and can preserve auxetic effects under large deformations. Based on an analytical mechanical model, a new family of auxetic chiral composites will be invented and their deformation mechanisms will be explored by finite element simulations, micro-polar theory, and mechanical experiments on multi-material 3D-printed specimens. Simultaneously, due to significant local rotation, these new micro-architectured materials provide excellent examples on the application of micro-polar theory and will be used to advance this important theory in mechanics. The rapid development of additive manufacturing (3D printing) enables easy and precise control of the geometry and material composition of micro-architectured hybrid materials, providing unprecedented opportunities to push the boundary of mechanics. This proposed research reveals a paradigm for using 3D printing as a tool to advance existing theories in mechanics and verify new engineering concepts.The creation of new knowledge on the mechanics of this new family of auxetic chiral composites is expected to have potential broad applications in designing lightweight materials for mechanical protection and energy absorption, biomedical materials and devices to improve public health, and metamaterials and mechano-adaptive composites. The outreach and engagement activities are designed to be integrated with the educational activities and will be largely focused on the engagement and retention of underrepresented groups by threading seemingly traditional mechanical engineering concepts with innovation interdisciplinary concepts. This will be accomplished by (1) engaging participants across all different levels, from graduate and undergraduate students, elementary and middle school students and teachers to practicing engineers, (2) strengthening curriculum within and across the disciplines of mechanics, biomimetics, and additive manufacturing, (3) collaborating with local, small/middle scale, and high-added value industries to facilitate knowledge dissemination and technology transfer, and (4) developing K-12 outreach activities to support the newly released Next Generation Science Standards.