Influence of Atmospheric Water on Surface Viscosity of Some Silicate Glasses

Abstract

The viscosities of soda-lime, lead, and borosilicate glasses as determined by the sinusoidal profile decay (SPD) method decreased with increase in the atmospheric water vapor pressure during measurement. Since the bulk viscosities were not affected by the presence of the atmospheric water, the change was discussed in terms of the water penetration into the surface layer of thickness about several to several tens of micrometers under the experimental conditions and the subsequent change in the surface layer viscocity. A linear relationship was observed between the reciprocal viscosity 1/η and square root of the water vapor pressure √P_H2O.