Analysis of residual stress fields from fictive temperature distributions within heat-affected zones of fused silica

Abstract

A simple model based on the measured fictive temperature distribution of fused silica was developed to determine the residual stress field of localized CO 2 laser-heated fused silica with an unknown thermal history. The proposed model assumes that the initial frozen-in state of fused silica is the zero-point of residual stresses and the generation of residual stresses results from the thermoelastic contraction differences of fused silica with different fictive temperatures from initial frozen-in temperatures to the ambient temperature. The spatially resolved fictive temperatures of the fused silica sample were characterized using confocal Raman microscopy, and the calculated residual stress fields agreed well with laser-induced critical fracture measurements and photoelastic measurements.