Fiber Lasers for Powertrain Welding

Fiber lasers aren’t always the best way to weld powertrains or other engine components, like differential gears, transmissions, driveshafts, or transmissions — unless you know how to control the laser output.

While completely optimizing powertrain component welding with fiber lasers involves multiple process factors, including laser power and gas delivery nozzles, the single biggest improvement comes from changing the intensity of the beam profile.

Learn how to make the right alterations and get the most out of fiber lasers to better assemble your metal automotive parts, from aluminum engine cylinders to drivetrains and clutch components.  

The Tech Briefs article “Fiber Lasers for Powertrain Welding” explores:


Transmission clutches and engine cylinders are made from difficult-to-weld materials like aluminum and galvanized steel. The adjustable ring mode laser enables galvanized steel welding without the need for a gap between the parts.

Learn how to use a beam profile consisting of a central spot, surrounded by another concentric ring of laser light. The power in the center and the ring can be independently adjusted on demand over a range of 1% to 100% of the nominal maximum output.

In this section of the article, a detailed schematic also demonstrates the five basic power patterns that can be achieved within the focused laser spot.


CO2 lasers are still employed to weld automobile powertrain components, since fiber lasers typically produce molten material near the welding arc, or spatter. Such contamination is particularly unacceptable when welding moving parts, such as powertrain gears or bearing surfaces. 

The Tech Briefs article reveals a weld cross section showing four 0.77 mm thick sheets of galvanized steel, welded together with zero gap. Photos from the feature article demonstrate that a properly configured fiber laser beam can deliver the same weld quality as a CO2 laser. 

The fiber laser welding parameters used in this case both reduced spatter and enabled higher processing speeds.


Hang-on parts like doors frequently have curved or unusual geometries, which can make the components difficult to weld. The “hang-ons” are also frequently made from aluminum, which can crack during the weld process.

Weld cross sections in the Tech Briefs article show the dramatic effect of changes in weld results, with just minor adjustments in focused spot intensity distribution. A slight change in the intensity profile, which increased the pre-and post-heating effect, produced a weld on a door with excellent penetration, at the same feed rate of 5 m/min.

Fiber lasers have a traditional intensity which is usually strongly peaked in the center; Learn how technologies like the Adjustable Ring Mode fiber laser from Coherent alter that intensity and improve weld quality when manufacturing of powertrains, engine cylinders, and drivetrains.

Fiber Lasers for Powertrain Welding