The dynamic impact response of giant buckyball C720 is investigated by using molecular dynamics simulations. The non-recoverable deformation of C720 makes it an ideal candidate for high-performance energy absorption. Firstly, mechanical behaviors under dynamic impact and low-speed crushing are simulated and modeled, which clarifies the buckling-related energy absorption mechanism. One-dimensional C720 arrays (both vertical and horizontal alignments) are studied at various impact speeds, which show that the energy absorption ability is dominated by the impact energy per buckyball and less sensitive to the number and arrangement direction of buckyballs. Three-dimensional stacking of buckyballs in simple cubic, body-centered cubic, hexagonal, and face-centered cubic forms are investigated. Stacking form with higher occupation density yields higher energy absorption. The present study may shed lights on employing C720 assembly as an advanced energy absorption system against low-speed impacts.
The work is supported by National Natural Science Foundation of China (11172231 and 11102099), DARPA (W91CRB-11-C-0112), National Science Foundation (CMMI-0643726), International joint research project sponsored by Tsinghua University (20121080050), Individual-research founding State Key Laboratory of Automotive Safety and Energy, Tsinghua University (ZZ2011-112), and World Class University program through the National Research Foundation of Korea (R32-2008-000-20042-0).
- Energy absorption