Effect of H 2 O 2 Treatment on Mechanical and Mechanochemical Properties of Fused Silica.

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. [ABSTRACT FROM AUTHOR]