  The objective of this study is to evaluate the mechanical properties and
energy absorption characteristics of the gyroid, dual-lattice and spinodoid
structures, as biomimetic lattices, through finite element analysis and
experimental characterisation. As part of the study, gyroid and dual-lattice
structures at 10 percent volume fraction were 3D-printed using an elastic
resin, and mechanically tested under uniaxial compression. Computational models
were calibrated to the observed experimental data and the response of higher
volume fraction structures were simulated in an explicit finite element solver.
Stress-strain data of groups of lattices at different volume fractions were
studied and energy absorption parameters including total energy absorbed per
unit volume, energy absorption efficiency and onset of densification strain
were calculated. Also, the structures were characterized into bending-dominant
and stretch-dominant structures, according to their nodal connectivity and
Gibson-and-Ashby's law. The results of the study showed that the dual-lattice
is capable of absorbing more energy at each volume fraction cohort. However,
gyroid structures showed higher energy absorption efficiency and the onset of
densification at higher strains. The spinodoid structure was found to be the
poorest structure in terms of energy absorption, specifically at low volume
fractions. Also, the results showed that the dual-lattice was a stretch
dominated structure, while the gyroid structure was a bending dominated
structure, which may be a reason that it is a better candidate for energy
absorption applications.
