The mechanics of additively manufactured reentrant honeycombs: apparent elastic modulus and energy absorption ability under cyclic loadings.

Abstract

Advances in additive manufacturing (AM) technologies have made possible the design and fabrication of more complex parts such as the cellular solids. Auxetic honeycombs are a type of cellular solid with already demonstrated enhanced mechanical properties and great potential as energy absorber. This work consists in the fabrication and characterization of reentrant honeycombs structures to study the feasibility of AM technology fused deposition modeling (fdm) as the manufacturing process and its effect on the mechanical properties of the printed parts. Numerical and experimental analysis were carried out to obtain the apparent elastic modulus of reentrant honeycombs and its relationship with the relative density of the specimens. Disadvantages of selecting fdm include low accuracy in the shapes printed and inability to print cell-wall thicknesses lower than 1 mm in cellular solids. A non-linear relationship between relative density of auxetic honeycombs and their apparent elastic modulus was found.