The Fracturing of Glass

This investigation into the mechanism explaining how glass cracks centers on an atomistic look at how water and other chemicals accelerate crack growth and how the acceleration can be slowed, stopped, or even reversed. Analysis of the kinetics of reactions of water and chemicals upon the glass uses Fourier-transform infrared spectroscopy; the technique is described. The method allows a prediction of the relative rates of crack growth in silica glass exposed to different chemicals within an order of magnitude dependent upon the rate of molecular diffusion near the crack tip and the rate of dissociative chemical reactions on the strained silicon-oxygen bond. Surface coatings are able to reduce this crack growth. -- AATA