Energy Absorption Properties of Periodic and Stochastic 3D Lattice Materials

Abstract

Architected lattices can be designed to have tailorable functionalities by controlling their constitutive elements. However, little work has been devoted to comparing energy absorption properties in different periodic three-dimensional geometries to each other and to comparable foam-like random structures. This knowledge is essential for the entire design process. In this work, the authors conduct a systematic and comprehensive computational study of the quasi-static and dynamic energy absorption properties of various different geometries. They test compression loading over strain rates varying from 1 to 10 4 s −1 . The authors analyze geometries with varying degrees of nodal connectivity, ranging from bending dominated to stretching dominated, at different orientations, and compare their response to equivalent stochastic lattices. Results show relatively high stress peaks in the periodic lattices, even in bending dominated lattices at certain orientations. Conversely, the stochastic geometries show a relatively constant stress response over large strains, which is ideal for energy absorbing applications. Still, results show that specific orientations of bending dominated periodic lattice geometries outperform their stochastic equivalents. This work can help to quickly identify the potential of different unit cell types and aid in the development of lattices for impulse mitigation applications, such as in protective sports equipment, automotive crashworthiness, and packaging.

3D-printed cellular tips for tuning fork atomic force microscopy in shear mode

“…As a succession to natural instances in motion deceleration, shockwave suppression, and mechanical force reduction 14 , porous structures widely found in biological skeletal systems such as cancellous bones have been extensively investigated in numerous energy-absorbing applications [15][16][17][18] . Emulating these geometrical constructions and coupling with advanced additive manufacturing techniques in microscale, artificial cellular microarchitectures, referred to as controlled microstructural architectured (CMA) material [19][20][21] , can be structurally programmed with a controllable geometry and spatial configuration for advantageous sizedependent metamechanical properties 22,23 , such as low density but strong robustness 24 , high stiffness-to-weight ratio 25 , excellent resilience 26,27 , mechanical tunability 28,29 , and in particular, energy absorption [30][31][32][33] . Hence, by employing this cellular hierarchy for the geometric design of the tip itself, the tip-sample interaction is anticipated to be reduced.…”

Effect of Fillets on Mechanical Properties of Lattice Structures Fabricated Using Multi-Jet Fusion Technology

“…An important characteristic of cellular structures is the ability to accommodate large deformations through material and/or topological nonlinearities [ 18 , 19 ]. This property has been exploited in protective devices, such as protective military and sports equipment [ 20 ], crashworthy vehicles, shoe midsoles [ 21 ], reusable energy absorption devices, truss-like energy-absorbing medical implants [ 22 ], soft robotic actuators and structures, having negative Poisson ratio effects [ 23 , 24 ]. During an energy-absorbing large deformation process, these structures tend to decrease the maximum stress transferred through the material by evenly distributing the stress until the structure is densified [ 25 ].…”

Programmed Plastic Deformation in Mathematically-Designed Architected Cellular Materials

“…The deformation mechanisms of architected cellular materials are rather complex to predict. Studies have shown that under a simple uniaxial compression experiment, the failure mechanism of a cellular material depends on many factors such as the cell type, parent materials, cell size, cell orientation, and post-processing history, such as heat treatment [33,53]. For example, a recent study investigating the compressive behavior of AlSi10Mg Gyroid structure revealed clear, cell size-dependent failure modes including the successive collapse of cells, brittle fractures, and the formation of shear bands.…”