Abstract
We present a comprehensive modeling and numerical study focusing on the energy quasi-static crushing behavior and energy absorption characteristics of hollow tube microlattice structures. The peak stress and effective plateau stress of the hollow microlattice structures are deduced for different geometrical parameters which gives volume and mass densities of energy absorption, Dv and Dm, scale with the relative density, ρ̄, as DV∼ρ̄1.5 and Dm∼ρ̄0.5, respectively, fitting very well to the experimental results of both 60° inclined and 90°predominately microlattices. Then the strategies for energy absorption enhancement are proposed for the engineering design of microlattice structures. By introducing a gradient in the thickness or radius of the lattice members, the buckle propagation can be modulated resulting in an increase in energy absorption density that can exceed 40%. Liquid filler is another approach to improve energy absorption by strengthening the microtruss via circumference expansion, and the gain may be over 100% in terms of volume density. Insight into the correlations between microlattice architecture and energy absorption performance combined with the high degree of architecture control paves the way for designing high performance microlattice structures for a range of impact and impulse mitigation applications for vehicles and structures.
Original language | English |
---|---|
Pages (from-to) | 39-49 |
Number of pages | 11 |
Journal | Composites Part B: Engineering |
Volume | 67 |
DOIs | |
Publication status | Published - Dec 2014 |
Externally published | Yes |
Bibliographical note
Acknowledgment:This investigation was sponsored by DARPA through the Soldier Protection Systems program managed by J. Goldwasser (contract no. W91CRB-11-C-0112). The views expressed are those of the authors and do not reflect the official policy or position of the Department of Defense or the U.S. Government. YL acknowledges additional support from the National Natural Science Foundation of China (11302163 and 11321062) and XC acknowledges additional support from the National Natural Science Foundation of China (11172231 and 11372241), the World Class University program through the National Research Foundation of Korea (R32-2008-000-20042-0), and the National Science Foundation (CMMI-0643726). The authors would like to thank W.B. Carter for useful discussions and A. Sorensen and C. Ro (HRL Laboratories) for help with sample preparation and testing.
Keywords
- B. Buckling
- B. Mechanical properties
- B. Plastic deformation
- C. Finite element analysis
- Microlattice structures