Seam welding of A3003 aluminum alloy using high-brightness pulsed slab YAG laser

Butt-welding A3003 aluminum alloys, penetration instability has been observed. The cause of penetration instability was studied and countermeasures were established. A slab laser was used for carrying out the welding experiment in order to exclude instability factors such as changes of the laser beam product. The laser beam product of slab lasers is constant in all power range. The penetration instability was observed at any combination of laser pulse width, laser peak power and laser focusing angle. To prevent the penetration instability of A3003 a high peak power, short width pulse was added before a usual rectangular pulse is effective. This short pre pulse does not melt aluminum alloy A3003.