Characterization of Micrometric and Localised Residual Stresses on Amorphous Materials Using Dispersion of Surface Acoustic Waves

Abstract

For amorphous materials such as glass, the fragility of the material can be limited using surface reinforcement by chemical tempering. The principle of chemical tempering consists in forming a superficial compression layer on the surface by immersing the glass in a solution of molten potassium nitrate. In this study, dispersion of surface ultrasonic waves caused by the presence of residual surface stresses was studied. The thickness and the level of the stressed cortical zones were estimated using an inverse method.