Improving the processing quality of transparent glass with a tripartite-interaction procedure

Laser processing plays a key role in the industrial manufacture. The transparent material processing with a visible nanosecond laser based on a tripartite-interaction procedure has proven to be an effective method, which has the advantages of low cost, high efficiency, and simplicity over the traditional direct processing by using a femtosecond laser. In our pre-study, by using an assisted metal foil attached to the rear surface of a transparent glass sheet, some holes can be drilled on the glass sheet with a visible nanosecond laser. Such a physical mechanism is based on the heat conduction, generation of stress and ablation among the laser beam, the glass sheet and the metal foil. However, the processing quality of the glass sheet during the previous process is still dissatisfied and remains to be improved. In this study, we demonstrated a new tripartite-interaction procedure among the laser beam, glass sheet and copper foil, i.e. attaching an assisted copper foil on the front surface of the glass sheet, to further improve the processing quality of the hybrid tripartite-interaction processing. The experimental results are compared with those of our previous work, indicating that drilled holes and grooves with less crack and better quality can be obtained by using the new procedure. Moreover, to analyze the reasons of obtaining less cracks and better quality, we have carried out a series of theoretical studies on simulating such a new tripartite-interaction process. According to some specific simulation results of the temperature and density variations in the glass and copper, we can analyze that the reduction of thermal damage on the glass sheet and the improvement on processing quality might be attributed to the thermal transfer induced by attenuated laser energy in such a configuration. Our results could be useful for the development of visible nanosecond laser processing in industrial applications.