Thermal effects of single-pulse laser irradiation on fused silica

Abstract

Most methods to research thermal effect are based on the analytical method, but he calculation processing is too complex, and we can get analytical solution only in a very small number of simple cases. We research the issue by use of finite element method (FEM). In this paper, the main research areas are as follows: The first, a theoretical mode of pulse laser leading to thermal stress damage of dielectric material is developed. Based on this theoretical model, transient distributions of temperature field and thermal stress field are analyzed by finite element method (FEM). The FEM method involves element discretion, element analysis, and overall analysis. Transient temperature field and stress field are simulated by using FEM software. Numerical results indicate: There is large temperature gradient in radial directions, while small temperature gradient exists in axis directions, and central temperature will be higher as power density of laser is higher. The results demonstrate that thermal stress damage is critical and circumferential stress play a main role in damage mechanism, the principle and methods of film measurement are summarized, the results in this paper may provide theoretical base for further research.