Shape transformers for crashworthiness of additively manufactured engineering resin lattice structures: Experimental and numerical investigations

Abstract

Cellular materials have superior specific properties (e.g., specific strength, stiffness, and energy absorption) as compared to their monolithic material counterparts. With rapid advancements in additive manufacturing technology, the uniquely complex geometry of these materials – particularly periodic lattices – can be easily reproduced for additional experimental research, characterization, and potential industrial applications. This work utilizes the idea of shape transformers – previously employed to describe the structural efficiency of beams subjected to bending – to define new strut-based lattices, whose struts do not have the typical solid, circular cross-section shape. Both experimental and numerical model results have shown that this design parameter can be utilized to manipulate the crashworthiness efficiency of lattice materials. It is found that designing with a square or a rectangular cross-section could increase the plateau stress by up to 52% while increasing the mass normalized specific energy absorption by up to 32%.