|About this Abstract
||Materials Science & Technology 2020
||Glasses, Optical Materials, and their Functional Applications: Current Issues in Science & Technology
||Photo-elastic Confirmation of Fast Surface Relaxation of Silica Glasses in the Presence of Water
||Bronson D. Hausmann, Emily Aaldenberg, Minoru Tomozawa
|On-Site Speaker (Planned)
||Bronson D. Hausmann
Fast surface stress relaxation has been found to occur in oxide glasses at temperatures far below the glass transition in the presence of water. The observed relaxation has been suggested previously to explain various unresolved phenomena related to the mechanical strength of glass. Until now, residual stress has only been indirectly demonstrated through mechanical analysis or IR peak shift. In the present work, residual stress profiles were calculated using common photo-elastic techniques. Optical retardance profiles were measured in silica glass fibers following heat treatments under bending. Silica glass rods were also analyzed following relaxation under a constant angle of twist. Such retardance profiles were obtained along the width of the glass samples for various stress-treated times and temperatures in air. The stress profiles were found to agree with an error function relaxation profile, supporting the theory of a mechanism controlled by water diffusion.