Mechanical Behavior and Crushing of Cellular Materials

University Of Texas At Austin, Austin TX

Investigators

Abstract

Solid foams have high stiffness- and strength-to-weight ratios, excellent energy absorption characteristics and exceptional insulation and acoustic properties. They are thus ideal materials as cores in sandwich structures, in impact mitigation and energy absorption applications in vehicles of all kinds, as insulation materials for sound and heat, for energy storage, etc. These characteristics arise from their cellular microstructure. This project uses X-ray tomography to characterize such microstructures. The geometry extracted is introduced into micromechanically accurate analytical and finite element models that are used together with the properties of the base material to calculate the mechanical response to compressive loads. The uniqueness of the project is that it models the initial elastic properties, the onset of yielding, the level and extent of the stress plateau and ends with densification. The new work will introduce the randomness of the microstructure to the models as well as the behavior under multiaxial and dynamically applied loads. Both polymeric and metallic open- and closed-cell foams will be analyzed. The project aims to bring science to a hitherto empirical subject. The models and closed-form expressions of properties developed can be used to design foams to fit the application. The project will train researchers to become future leaders in multidisciplinary research in academia and industry. The results are disseminated through journal publications, conferences and university lectures and through contact with international and industrial researchers in the field. The latter serve to disseminate results directly to users and help keep the project pointed towards what is practical.