Ion-beam-induced stiffening of nanoporous silica

Low-density nanoporous solids have notoriously poor mechanical properties. Here, we show that light-ion irradiation can significantly improve the elastic modulus and hardness of low-density silica nanofoams (aerogels). Both elastic modulus and hardness saturate with ion fluence, and the saturation level increases with the ion stopping power. Such ion-beam stiffening is attributed to local material modification along ion tracks. (fast track communication)