Glass welding by ultra-short laser pulses: Influence of the residual mechanical stresses on the assembly strength

Abstract

In this work we study glass welding by ultrashort laser pulses. We evaluate the influence of the residual mechanical stresses due to the welding process of the borosilicate glass on the assembly strength and resistance to mechanical strain. Sample characterization is performed thanks to a three-point bending test and cross polarization optical microscopy. Welding regimes with and without heat accumulation are considered. The wavelength and pulse duration of the laser used in this study are 1030nm and 350 fs respectively. The influence of pulse energy (0.8µJ to 1.2µJ), repetition rate (100 to 500kHz), focusing condition and laser trajectory is discussed in terms of mechanical resistance and of the extent of the residual mechanical stresses.In this work we study glass welding by ultrashort laser pulses. We evaluate the influence of the residual mechanical stresses due to the welding process of the borosilicate glass on the assembly strength and resistance to mechanical strain. Sample characterization is performed thanks to a three-point bending test and cross polarization optical microscopy. Welding regimes with and without heat accumulation are considered. The wavelength and pulse duration of the laser used in this study are 1030nm and 350 fs respectively. The influence of pulse energy (0.8µJ to 1.2µJ), repetition rate (100 to 500kHz), focusing condition and laser trajectory is discussed in terms of mechanical resistance and of the extent of the residual mechanical stresses.