Energy absorption of all-PET 2nd order hierarchical sandwich structures under quasi-static loading conditions

Abstract

Abstract The impact performance of lightweight structures represents an important design criterion in modern applications. Within this framework, the self-reinforced PET (poly-ethylene terephthalate) materials prove to exhibit large deformations till failure, which enables them to be proper candidates for impact energy absorption. Apart from the advantages offered by the lightweight characteristics, they are made of recyclable materials, an additional reason for their consideration in engineering applications. In this paper, the behavior of a hierarchical sandwich structure made out of self-reinforced PET (matrix & fibre) combined with PET foam is numerically investigated with respect to the specific energy absorption (SEA) capacity in out-of-plane quasi-static loading conditions. The numerical model of the structure is developed and its behavior is firstly validated through experimental tests. The specific energy absorption is further on determined for several geometric configurations of the hierarchical sandwich structure and compared with the behavior of other cellular structures found in the technical literature. A competitive behavior is observed with respect to impact energy absorption.