Laser welding

Laser welding works VERY WELL on thin materials.  In fact laser welding is the best welding process for thin materials, ranging from 0.020″ (0.5mm) to quarter inch (6mm).   We even sell pulsed laser welders that work wonderfully on 0.004″ (0.1mm) stainless steel and inconel.  Our pulsed welders are specially designed for pulsed laser welding jewelry, and for mold repairs using very fine 0.3 or 0.4mm wire.

We can easily weld thin materials that MIG and TIG welding cannot.  For example, the image on the left shows a lap weld on 0.040″ (1mm) aluminum, which was welded with full penetration and no distortion.  The welding was done at half an inch per second travel speed, but could be ran faster if desired.  Perfect for sign manufacturers using thin material to fabricate aluminum signs.  The welding power can be reduced to prevent marking or penetration on the back face.

Laser welding is as good as TIG welding, and better in every way in our opinion.  We believe laser welding will replace TIG for sheet metal up to a quarter inch thick.  Laser welding has the following advantages over TIG welding:

• Much faster.  We typically weld at 1/2″ per second, and can run faster.
• Easier.  Laser welding requires much less skill.  TIG is difficult.
• Semi-automated.  Laser welding parameters and wire feed control the welding.  Good welds can be repeated time after time.
• Better appearance.  Laser welding can be smooth, or if required you can generate a “stack of dimes” with pulsed settings.  
• Stronger.  Laser welding uses a beam 0.004″ wide which inputs the least amount of heat required to make a good weld.  TIG welding uses an arc approximately 1/8″ wide and the slow travel speed excessively heats the metal, annealing it back a “soft” condition, destroying the microstrure.
• Less distortion.  Laser welding puts in far less heat, and typically has one quarter of the distortion of TIG.
• Less energy consumption.  We calculated that our laser welders use 18% to 25% of the electrical energy a TIG does, based on an 1/8″ butt weld.  A HUGE saving with very green environmental credentials.
• Less gas consumption.  Welding at five times the speed uses far less gas, saving cost and once again being “green”.
• Far lower cost overall.  Add up all of the above savings including less staff and less skilled welders.  Then add on the saving from faster throughput and lower overheads.

The only disadvantage of laser welding is eye safety.  Refer to our laser safety section for full details.

Is laser welding as strong as MIG?

Laser welding is as strong as MIG, and should be stronger in most cases.  The heat input is less with laser welding, which is why it causes less distortion and staining.  MIG’s extra heat input anneals the metal, reducing its strength compared to laser welding.  The only advantage of MIG is a larger weld fillet, but the metal next to the weld will be weaker than if it was laser welded and that is the key determinant in the real world, in most situations.

The only time we’ve seen laser welding not as strong as we’d like is when welding straight over galvanizing, where the lower heat input didn’t burn the zinc away as much as MIG does.  Turning the laser power up burns off more zinc and increases the strength.  However MIG welding can easily be too cold, which causes weak welds.