CAREER: Designing Novel Structural Surfaces for Desired Vibration Transmission and Attenuation

这个教师早期职业发展（CAREER）项目将研究实验和建模技术，这将使多尺度界面模型的制定。界面是结构组件中最具柔顺性和耗散性的部位，其特性决定了承载结构的动力响应。有限的理解的基础上的管理机制，导致描述的界面属性是基于有限的有效性和适用性的经验法则。PI的职业目标是研究决定界面特性的因素，并将其调整为结构内所需的振动传输和衰减。作为该项目的一部分，制定的模型将占界面的长度和速度依赖的响应，并将用于设计单一材料的表面与可调结构的完整性，振动传输和衰减特性。这种新颖的设计方法为振动控制、噪声消除、减震以及能量存储和传输开辟了新的途径。最新的激光加工技术，使可扩展的表面图案化技术将用于制造接口进行测试和表征，在这个项目中。该奖项的教育目标是通过暑期培训计划和科学展览的研究经验，使学生，高中教师和公众接触力学和动力学研究。PI还将根据主动和体验式学习原则制定新的课程，以解决科学，技术，工程和数学的低保留率问题。活动将包括小组工作，多媒体项目，锦标赛式的设计竞赛，和远程访问实验到PI的本科和研究生课程。这个CAREER奖开发多尺度界面模型，并使用它们来实现所需的动态响应在承重结构。独特的原位透射电子显微镜划痕试验，和多尺度实验将进行研究如何位错，裂纹和相干滑移影响界面对外部负载的响应。多尺度界面模型将在这些实验之后开发。这些模型的可扩展性，宏观界面将通过测试表面控制的长度尺度进行验证。由于其准确性，效率和物理基础，这些模型将提供一个有效的解决方案，棘手的大型结构动力学问题的界面。使用这些界面模型，PI将优化界面，以提高阻尼品质因数和宽频带隙，这两者都调节结构的振动传递和衰减特性。最佳接口将被制造并在瞬态和谐波负载下进行测试。

This Faculty Early Career Development (CAREER) project will investigate experimental and modeling techniques that will enable the formulation of multiscale interface models. Interfaces are the most compliant and dissipative sites in structural assemblies, and their properties govern the dynamic response of load-bearing structures. Limited understanding of underlying governing mechanisms has lead to descriptions of interface properties that are based on empirical laws of limited validity and applicability. The PI's CAREER goal is to investigate the factors determining interface properties, and tailor them for desired vibration transmission and attenuation within a structure. The models formulated as part of this project will account for the length and velocity-dependent response of interfaces and will be employed to design single-material surfaces with tunable structural integrity, and vibration transmission and attenuation characteristics. This novel design approach opens new avenues in vibration control, noise cancellation, shock mitigation, and energy storage and transfer. Latest laser processing techniques enabling scalable surface patterning techniques will be used to fabricate interfaces to be tested and characterized in this project. The educational goal of this award is to expose the students, high school teachers and the general public to contact mechanics and dynamics research through research experiences in summer training programs and scientific exhibitions. The PI will also develop a new curriculum based on active and experiential learning principles to address low retention rates in science, technology, engineering and mathematics. Activities will incorporate group work, multimedia projects, tournament-style design competitions, and remote-access experiments into the PI's undergraduate and graduate courses.This CAREER award develops multiscale interface models, and uses them to achieve desired dynamic response in load-bearing structures. Unique in-situ transmission electron microscope scratch tests, and multiscale experiments will be conducted to study how dislocations, cracks and coherent slip influence the interface response to external loading. Multiscale interface models will be developed after those experiments. Scalability of those models to macroscale interfaces will be validated by testing surfaces with controlled length scales. Thanks to their accuracy, efficiency and physical-basis, those models will provide an effective solution to intractable large-scale structural dynamics problems involving interfaces. Using those interface models, the PI will optimize interfaces for enhanced damping figure of merit, and broad frequency band gaps, both of which regulate vibration transmission and attenuation properties of structures. Optimum interfaces will then be manufactured and tested under transient and harmonic loading.