Evolution Regularity of Continuous Surface Structures Shaped by Laser-Supported Fictive-Temperature Modifying

Abstract

The influence of residual heat on the fictive temperature modification zone of fused silica for different CO2 laser scanning time intervals was investigated to precisely control the profiles of hydrofluoric (HF) acid-etched fused silica surface, which were formed by the increasing HF acid-etching rate for fused silica with increasing fictive temperature induced by CO2 laser scanning. The surface profiles of HF acid-etched fused silica treated by different scanning time intervals of CO2 laser were measured by a stylus profilometry, and experimental results indicate that the CO2 laser scanning time intervals intensively influence the HF acid-etched surface profiles of fused silica. The increasing depth of surface profiles treated by shorter scanning time intervals shows that the fictive temperature modification zone significantly expands. Numerical simulations of the fictive temperature modification zone induced by different scanning time intervals indicate that the residual heat of CO2 laser scanning with shorter time intervals leads to a dramatical increase in the fictive temperature modification zone. By adjusting the residual heat of CO2 laser scanning intervals, various surface profiles of fused silica can be obtained by HF acid-etching of fused silica.