Shape memory-based lattice metamaterial: the octet truss cell

Lattice metamaterial attracted great attention in the last years due to their intelligent behaviour when subjected to external stimuli, which is also denoted as shape memory effect. This is the principle on how the 4D Additive Manufacturing is based on: it is possible to create complex geometry making the material “programmable” building up self-assembly structures. In this preliminary study, the octet lattice metamaterial has been selected to evaluate its performance by taking into account of shape memory effect investigating on its great properties in adaptability in shock absorption, negative Poisson’s ratio, high stiffness and weight efficiency with previous studies conducted in literature; its structure as designed on the commercial software ABAQUS. Through the finite element analysis has been possible to perform the structure under uniaxial compression test studying its response under specific loads changing geometrical configurations -e.g., relative density, diameter of truss- to fully understand the mechanism of the octet lattice metamaterial. The preliminary results show clearly great potential offered by octet truss lattice metamaterial with shape memory effect in terms of shape and stress recovery and in terms of planned structure degradation which could be advantageously exploited in future for many industrial applications.