Parts | Days | Selection | Search | Updates | Downloads | Help
MM: Fachverband Metall- und Materialphysik
MM 19: Mechanical Properties I
MM 19.3: Talk
Tuesday, March 8, 2016, 10:45–11:00, H52
Metamaterials using buckling instabilities for reusable energy absorbers — •Tobias Frenzel1, Claudio Findeisen2,3, Muamer Kadic1, Peter Gumbsch2,3,4, and Martin Wegener1,4 — 1Institute of Applied Physics, Karlsruhe Institute of Technology (KIT), 76128 Karlsruhe, Germany — 2Institute for Applied Materials, Karlsruhe Institute of Technology (KIT), 76128 Karlsruhe, Germany — 3Fraunhofer Institute for Mechanics of Materials IWM, 79108 Freiburg, Germany — 4Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), 76128 Karlsruhe, Germany
Commonly, structures and materials for mechanical energy absorption exploit either viscoelasticity or plasticity. While viscoelasticity leads to a reusable, yet time-dependent behavior, plasticity is not influenced by the timescale, yet the structural deformation is irreversible. In this work, we introduce a new class of artificial material, which exploits elastic buckling in a uniaxial micro-lattice as a mechanism for energy absorption. Most importantly the energy is not dissipated by local effects, e.g., within one unit cell, but by the coupling of N effectively nonlinear springs in series. By tailoring the buckling elements, either a hysteretic, yet repeatable, or a multi-stable behavior enabling for programmability can be achieved. Furthermore, the shape of the stress-strain curves can be tailored, which allows for control over peak forces. Experiments performed on polymer micro-structures made by direct laser writing scaled to aluminum show specific energy absorption comparable to state-of-the-art aluminum-foams.