Microplasticity induced damping of aluminum foam

Abstract

Aluminum foam's high dampening properties provide substantial potential for reducing mechanical vibration and noise in lightweight applications. However, inadequate understanding of the damping mechanism cannot provide sufficient theoretical guidance to improve the damping performances. In this study, the DMA (Dynamic Mechanical Analysis) tests results were compared with the numerical simulations to examine the correlation between local plastic deformation and the aluminum foam's damping performances. The 3D geometric modeling of aluminum foam was imported into ABAQUS/Explicit. The loss factors derived from the plastic energy dissipation of the numerical simulations are well consistent with the DMA tests. The simulation showed that the cell walls produces localized plastic deformation at the strains well below the elastic limit of engineering point view. Meanwhile, the plateau borders remain elastic, and thereby maintain the overall elasticity of aluminum foams. Aluminum foam's damping properties are tailorable by altering the pore size and local solid materials thickness. Under vibration loading, the aluminum foam sandwich offers higher damping performances due to greater local plastic deformation within the overall elastic range of the components.