Densification Of Glass Surfaces By Grinding And Polishing

Compared to multicomponent optical glasses, ground or polished fused-silica exhibits low surface micro-roughness and sub surface damage, low grinding-induced residual stresses, and low removal rates. When subjected to sufficiently large compressive stresses, fused silica and other high-Si02 content glasses also densify permanently, thus increasing the index of refraction. The densification is facilitated by shear stresses. Densification under large applied pressure and shear stresses, as might be expected to occur in polishing and grinding, is described here by a simple constitutive model.