Damping Properties of Polymer Lattice Materials

Abstract

Microlattices, or microtrusses, are periodic open-cell structures formed by a network of interconnecting struts (Figure 1). With deliberate material arrangement – used to affect efficient manipulation of the load paths – these engineered architectures can significantly enhance the bulk material properties per unit weight. Cellular materials can also possess multifunctionality with potential to provide a suitable combination of specific strength and stiffness, vibration suppression, and acoustic absorption that could benefit a number of commercial undersea applications; for example, pressure vessels and fairings fabricated from sandwich structures with microlattice cores can potentially exploit energy absorption capabilities of these cellular solids to reduce the vehicle noise signature. The present work seeks to characterize the viscoelastic properties of several cellular architectures to better understand the frequency-dependent damping of these lattice materials. A dynamic mechanical analyzer (DMA) is used to collect experimental data for comparison with predicted behavior derived from finite element analysis (FEA). The recovery and capacity for energy absorption of each cell topology are assessed, and the details of the analytical techniques and experimental program are provided.