0000000000586326
AUTHOR
Nicolas Pierron
Determination of an empirical law of aluminium and magnesium alloys absorption coefficient during Nd :YAG laser interaction
International audience; Welding laser modelling requires knowledge about relative changes of many thermo-physical parameters involved in the interaction. The absorptivity of the material is one of the most important. In this study, experimental measurements of absorptivity with an integrating sphere on two alloys (aluminium and magnesium) were made. These results were compared with an analytical calculation that takes into account the trapping of the beam by multiple reflections inside the keyhole. Based on a statistical method, an empirical law is proposed connecting absorptivity with the peak power of the laser and the duration of interaction. During the interaction, two distinct phenomen…
Study of magnesium and aluminum alloys absorption coefficient during Nd:YAG laser interaction
International audience; In laser processes, the absorption factor of laser Nd:YAG by metals plays a very important role. In order to model laser welding, we need to know its evolution during the process. The theoretical calculation does not enable the prediction of the absorption factor in the case of a keyhole mode. It is difficult to predict the effect of plasma and recoil pressure on the shape of the keyhole. In this paper, an integrating sphere is used to determine the absorption factor during the laser process, which is carried out on two types of magnesium alloys (WE43 and RZ5) and an aluminum alloy. We obtain the evolution in time of the absorption factor according to different steps…