CAREER: Nudging and Leveraging the Onset of Buckling in Architected Materials for Performance Gains

该学院早期职业发展（CAREER）奖支持结合复杂代数，应用数学，工程力学和应用物理学的思想的研究，以推进对微屈曲和后微屈曲行为的基本理解和控制。力学和材料界已经将他们的兴趣转向使用以晶胞设计为中心的材料结构，以实现奇异的材料特性和功能，从而产生了被称为建筑材料的领域。在建筑材料中观察到的不寻常的性质和功能通常是通过故意利用弹性微屈曲来获得的，即，由于负载，形成材料的单元壁和边缘的形状不稳定。该研究项目将为微调结构材料中的微屈曲不稳定性创造一条途径，以利用定制的机械行为。研究成果有可能影响医学，运输，航空航天，建筑和人员保护的应用。该奖项还将支持一项广泛的教育计划，通过改进课程，在当地儿童博物馆开展外联活动，通过YouTube视频传播研究，以及招聘，扩大拉丁裔和西班牙裔学生在STEM企业中的参与。指导和培训本科生和研究生。这个职业生涯的研究计划的目标是产生一个新的理解如何弹性的发病可以修改、控制和设计周期性结构材料中的微屈曲，以实现所需的后微屈曲行为，从而实现定制和可调的有效机械行为。本研究的主要贡献在于：（1）提出了一种基于超复数有限元方法的计算框架，用于量化和排序设计参数及其相互作用的影响;（2）提出了一种基于矩的快速不确定性量化的新方法，用于预测由于制造和加载条件引起的不确定性引起的变异性;以及（3）物理“轻推”的概念作为在可用屈曲状态之间转换的机制，并且因此控制结构化材料中微屈曲的开始。该奖项反映了NSF的法定使命，并被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

This Faculty Early Career Development (CAREER) award supports research that combines ideas drawn from complex algebra, applied mathematics, engineering mechanics, and applied physics to advance the fundamental understanding and controlling of the onset of micro-buckling and post micro-buckling behavior of architected materials. The mechanics and materials communities have turned their interest to using material architecture centered on unit cell designs to enable exotic material properties and functionalities, giving rise to the field known as architected materials. The unusual sets of properties and functionalities observed in architected materials are often obtained by deliberatively exploiting elastic micro-buckling, i.e., instability in the shape of the cell walls and edges forming the material due to loading. This research project will create a pathway for fine-tuning the micro-buckling instabilities in architected materials to harness tailored mechanical behaviors. The research outcomes have the potential to impact applications in medicine, transportation, aerospace, construction, and personnel protection. The award will also support an extensive education plan to broaden the participation of Latinx and Hispanics students in the STEM enterprise through curriculum improvements, outreach activities at a local museum for children, dissemination of research through YouTube videos, and recruitment, mentoring and training of undergraduate and graduate students.The objective of this CAREER research program is to generate a new understanding of how the onset of elastic micro-buckling in periodic architected materials can be modified, controlled, and designed to achieve desired post micro-buckling behavior and thus, custom and tunable effective mechanical behaviors. The key intellectual contributions of this research are: (1) a novel computational framework based on hypercomplex finite element method to quantify and rank the influence of design parameters and their interactions; (2) a new method based on moment-based fast uncertainty quantification that predicts the variability due to uncertainties emanating from fabrication and loading conditions; and (3) the concept of the physical “nudge” as a mechanism to transition between the available buckling states and, thus, to control the onset of micro-buckling in architected materials. The nudge could be initiated through material actuation, structural design, or any other suitable measure.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.