Shape recovery effect of 3D printed polymeric honeycomb

Polymeric honeycombs, with their lightweight, high stiffness-to-weight ratio, and welldeveloped energy absorption characteristics, have been widely used in engineering applications. In this work, we report the shape recovery effect in a 3D-inkjet-printed honeycomb core. Shape recovery effect, in which the honeycomb slowly recovers back to near its original shape, was observed after the release of compressive loading. Cyclic compression tests were carried out to study the shape recovery characteristics and factors affecting strain recovery in the 3D printed honeycombs. The factors such as honeycomb design shape, loading rate, and number of compressions were investigated. Flatwise compression tests were carried out on three different honeycomb shapes, namely hexagon, triangle, and circular, at three different loading rates. Three stages of shape recovery were identified and general conclusions on the factors affecting the shape recovery were proposed.