Dynamic Compression of an Interpenetrating Phase Composite (IPC) Foam: Measurements and Finite Element Modeling

Abstract

Dynamic compression response of Syntactic Foam (SF)–aluminum foam Interpenetrating Phase Composites (IPC) is measured. By infusing uncured syntactic foam (epoxy filled with hollow microballoons) into an open-cell aluminum network, a 3D interpenetrating structure is obtained. The uniaxial compression responses are measured at ~1500 /sec using a split Hopkinson pressure bar set up. The effect of volume fraction of microballoons on the compression response of IPC is examined in terms of yield stress, plateau stress and energy absorption. The response of IPC samples are also compared with those made using syntactic foam alone. For all volume fractions of microballoons, the IPC samples have better compression characteristics when compared to the corresponding syntactic foam samples. The failure modes of SF and IPC foams are examined both optically (using high-speed photography) and microscopically. The measured dynamic responses of SF are used in a finite element model based on a Kelvin cell representation of the IPC structure. Using infinite elements and measured particle velocity histories as input boundary conditions, the compression response of IPC foams have been successfully captured