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Title: Dynamic energy absorption characteristics of hollow microlattice structures

Abstract

Hollow microlattice structures are promising candidates for advanced energy absorption and their characteristics under dynamic crushing are explored. The energy absorption can be significantly enhanced by inertial stabilization, shock wave effect and strain rate hardening effect. In this paper we combine theoretical analysis and comprehensive finite element method simulation to decouple the three effects, and then obtain a simple model to predict the overall dynamic effects of hollow microlattice structures. Inertial stabilization originates from the suppression of sudden crushing of the microlattice and its contribution scales with the crushing speed, v. Shock wave effect comes from the discontinuity across the plastic shock wave front during dynamic loading and its contribution scales with e. The strain rate effect increases the effective yield strength upon dynamic deformation and increases the energy absorption density. A mechanism map is established that illustrates the dominance of these three dynamic effects at a range of crushing speeds. Compared with quasi-static loading, the energy absorption capacity a dynamic loading of 250 m/s can be enhanced by an order of magnitude. The study may shed useful insight on designing and optimizing the energy absorption performance of hollow microlattice structures under various dynamic loads. (C) 2014 Elsevier Ltd. Allmore » rights reserved.« less

Authors:
; ;
Publication Date:
Sponsoring Org.:
USDOE Advanced Research Projects Agency - Energy (ARPA-E)
OSTI Identifier:
1211084
DOE Contract Number:
DE-AR0000396
Resource Type:
Journal Article
Resource Relation:
Journal Name: Mechanics of Materials; Journal Volume: 77
Country of Publication:
United States
Language:
English

Citation Formats

Liu, YL, Schaedler, TA, and Chen, X. Dynamic energy absorption characteristics of hollow microlattice structures. United States: N. p., 2014. Web. doi:10.1016/j.mechmat.2014.06.008.
Liu, YL, Schaedler, TA, & Chen, X. Dynamic energy absorption characteristics of hollow microlattice structures. United States. doi:10.1016/j.mechmat.2014.06.008.
Liu, YL, Schaedler, TA, and Chen, X. 2014. "Dynamic energy absorption characteristics of hollow microlattice structures". United States. doi:10.1016/j.mechmat.2014.06.008.
@article{osti_1211084,
title = {Dynamic energy absorption characteristics of hollow microlattice structures},
author = {Liu, YL and Schaedler, TA and Chen, X},
abstractNote = {Hollow microlattice structures are promising candidates for advanced energy absorption and their characteristics under dynamic crushing are explored. The energy absorption can be significantly enhanced by inertial stabilization, shock wave effect and strain rate hardening effect. In this paper we combine theoretical analysis and comprehensive finite element method simulation to decouple the three effects, and then obtain a simple model to predict the overall dynamic effects of hollow microlattice structures. Inertial stabilization originates from the suppression of sudden crushing of the microlattice and its contribution scales with the crushing speed, v. Shock wave effect comes from the discontinuity across the plastic shock wave front during dynamic loading and its contribution scales with e. The strain rate effect increases the effective yield strength upon dynamic deformation and increases the energy absorption density. A mechanism map is established that illustrates the dominance of these three dynamic effects at a range of crushing speeds. Compared with quasi-static loading, the energy absorption capacity a dynamic loading of 250 m/s can be enhanced by an order of magnitude. The study may shed useful insight on designing and optimizing the energy absorption performance of hollow microlattice structures under various dynamic loads. (C) 2014 Elsevier Ltd. All rights reserved.},
doi = {10.1016/j.mechmat.2014.06.008},
journal = {Mechanics of Materials},
number = ,
volume = 77,
place = {United States},
year = 2014,
month =
}
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