Properties and characteristics of laser beam welds of automotive aluminum alloys

A 14 kW CO₂ laser and reflective optics were utilized to produce specimens for obtaining typical joint properties associated with laser beam welds of automotive aluminum alloys. The results of static and dynamic testing of these welds indicated that the laser beam welding process is capable of producing high quality welds. In all cases, the measured yield strength of butt welds exceeded the minimum yield strength of base material specified for these alloys. Post weld aging of the heat treatable alloys resulted in a moderate increase in strength of butt welds but virtually no effect on joint strength of lap welds. Butt welds produced with filler metal additions on the non-heat treatable alloys exhibited improved joint strength in comparison to welds produced autogenously. Butt welds displayed, as expected, displayed significantly higher fatigue endurance when compared to lap welds. The welds produced with the non-heat treatable alloys displayed better formability than the heat treatable alloys and slightly lower corrosion resistance.