Laser welding characteristics of aluminium alloys for automotive applications

摘要

Laser welding features a rapid heating/rapid cooling thermal cycle. The YAG laser offers a good combination of high power and good beam quality while providing better absorbency on aluminium alloys than the CO_2 laser. It further ensures a lower heat input and better stabilisation of welding phenomena than alternative joining methods. In a comparison with available alternative joining methods, this paper accordingly shows laser welding to be suitable as a welding technology able to expand allowable levels of impurities and thus contribute to wider application of aluminium recycling materials. Laser welding is also shown to be able to suppress weld microcracking and to prevent strength loss during welding of heat-treatable Al-Mg-Si alloys offering good recycling prospects.