Energy absorption ability of buckyball C₇₂₀ at low impact speed: A numerical study based on molecular dynamics

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.