Enhanced resistance of nanocellular silica to dynamic indentation

Compared with solids, cellular materials are more lightweight yet usually weaker due to their large porosities. In the current study, it is discovered that the dynamic penetration resistance of nanocellular silica could be effectively higher than that of solid silica when the cell size is smaller than ~100 nm. This phenomenon is attributed to the local hardening that happens when the cell size is sufficiently small and the cell collapse is sufficiently fast. The finding paves a road to the development of strong and lightweight cellular materials.