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

University Of Wisconsin-Madison, Madison WI

Investigators

Abstract

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.