Nanoindentation creep dependent deformation process of silica and soda lime silicate glass

Abstract

In this study, the time dependent deformation of soda lime silicate and silica glass surfaces is investigated with nanoindentation creep tests. The results reveal that the nanomechanical properties of both glasses decrease with holding time. In addition, a quick recovery in the residual depth of nanoindentation imprint of both glasses has also been found after the indenter tip is retracted and before atomic force microscopy. Furthermore, the inelastic volume of glass surfaces within nanoindentation tests is quantified into densified and shear flow with annealing, and it is found that both the densified and shear flow volume of both glasses increase with holding time, but the recovery ratio of both glasses decreases with holding time, which is due to a faster increase in indentation volume with holding time compared with densified volume. Finally, a model of creep-induced deformation of glass surfaces is proposed to complement the creep-induced deformation process of silicate glasses.