Inert strength measurement on silica soaked at 250°C in liquid water and water vapour

Abstract

The effect of water soaking and heat-treatment in saturated water vapour at 250°C for 192 h on the strength of silica glass is studied. Bending strength meaurements in liquid nitrogen showed a clear increase of the inert strength for heat-treated specimens over that of the untreated material. The increase in strength is interpreted as the consequence of water diffusion into exposed surfaces of the test specimen, which results in swelling of the glass and shielding of cracks, present in the surface of the glass. Experimental results are compared with theoretical predictions.