Jeon, Seung-Yeol Shen, Beijun Traugutt, Nicholas A. Zhu, Zeyu Fang, Lichen Yakacki, Christopher M. Nguyen, Thao D. Kang, Sung Hoon 2024-01-19T12:30:25Z 2024-01-19T12:30:25Z 2022-04-05 2022-04 0935-9648 https://pubs.kist.re.kr/handle/201004/115470 A unique rate-dependent energy absorption behavior of liquid crystal elastomer (LCE)-based architected materials is reported. The architected materials consist of repeating unit cells of bistable tilted LCE beams sandwiched between stiff supports. The viscoelastic behavior of the LCE causes the energy absorption to increase with strain rate according to a power-law relationship, which can be modulated by changing the degree of mesogen alignment and the loading direction relative to the director. For a strain rate of 600 s(-1), the unit cell exhibits up to a 5 MJ m(-3) energy absorption density, which is two orders of magnitude higher than the same structure fabricated from poly(dimethylsiloxane) elastomer and is comparable to the dissipation from irreversible plastic deformation exhibited by denser metals. For a multilayered structure of unit cells, nonuniform buckling of the different layers produces additional viscoelastic dissipation. This synergistic interaction between viscoelastic dissipation and snap-through buckling causes the energy absorption density to increase with the number of layers. The sequence of cell collapse can be controlled by grading the beam thickness to further promote viscous dissipation and enhance the energy absorption density. It is envisioned that the study can contribute to the development of lightweight extreme energy-absorbing metamaterials. English WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Synergistic Energy Absorption Mechanisms of Architected Liquid Crystal Elastomers Article 10.1002/adma.202200272 1 Advanced Materials, v.34, no.14 Advanced Materials 34 14 Y scie scopus 000762589000001 2-s2.0-85125500350 Chemistry, Multidisciplinary Chemistry, Physical Nanoscience & Nanotechnology Materials Science, Multidisciplinary Physics, Applied Physics, Condensed Matter Chemistry Science & Technology - Other Topics Materials Science Physics Article VISCOELASTICITY DISSIPATION BEHAVIOR energy absorption liquid crystal elastomers metamaterial power-law relation stacking effect viscoelasticity