The effect of nodal topology on cellular solid mechanics

Abstract

Additive manufacturing allows material structuring, supporting the fabrication of multiple-level structures or metamaterials. Through the lens of classical stress reduction, nature’s cellular solid structures feature stress-homogenizing nodal topologies. Avian long bones are an example. Research into the mechanics of open cell cellular solids seems focused on the effectiveness of unit cell architecture and neglects the detailed behavior of constituent nodes. Several specimen series were printed on the nodal- and cellular solid-levels of analysis, all with varying nodal topologies. A discussion of force-displacement and digital image correlation experimental data is had; the cellular solid deflection rigidity seems highly sensitive to nodal topology under quasi-static compression. It is thought that bioinspired profiles successfully homogenize stress and improve load transfer, mitigating nodal softening: peak stresses and the propagation of nodal torsion into adjoining strut deflection decreased. This sensitivity is relevant for lightweight strain energy absorption and stiffness provision, and demands further research.