Laser Welding AluminiumEarly attempts to weld aluminium with lasers were fraught with difficulties, mainly due to the highly reflective metal surface. While this still presents problems, successful welds in aluminium can now be made using CO2 and YAG lasers. Laser welding may be carried out with or without the addition of filler wire. Welding without filler wire uses square-edged butt joints or lap joints, but for some alloys and applications extra filler metal of suitable composition may be placed in position prior to welding. The shielding gas for laser welding may be either argon or helium. Application is normally restricted to material up to 6mm or so thick and good, sound welds can be achieved. The problems encountered most frequently are porosity, cracking, and weld drop-through. The main potential safety hazards are electrical and radiation from the laser beam but enclosure, micro-switch cut off devices, and a strict operating regime can overcome these problems.
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