Effect of H2O2 Treatment on Mechanical and Mechanochemical Properties of Fused Silica

Abstract

The surface properties of fused silica (FS) change after H2O2 treatment, but the surface and subsurface damage behaviors and their mechanisms under various physical contact conditions have not been elucidated yet. This work investigated the effect of H2O2 treatment on mechanical and mechanochemical properties of FS surface. The results show that the hydrophilicity and adsorbed water film thickness of the FS surface increase with the concentration of H2O2 solution. The surface damage, nanowear, and subsurface deformation of FS caused by indentation increase with the concentration of H2O2 solution, while the nanohardness and reduced modulus decrease. Further analysis revealed that the water activity on the FS surface plays a critical role in reducing the mechanical and mechanochemical properties. In addition, the treatment with H2O2 solution on the FS surface shows a weakly corrosive effect, which implies the H2O2 treatment can be an alternative method to remove the surface defects on FS optics.