Laser spot welding is a non-contact process which uses a laser to create a single weld spot to weld metals together. Lasers are capable of delivering a pulse of light with accurate, repeatable energy and duration. When the pulse is focused into one place – a small spot – (adjustable anywhere from approximately 0.1 to 3.0 mm in diameter) on the part, the energy density becomes quite large. The light is absorbed by the material causing a “keyhole effect” as the focused beam drills into, vaporizes, and melts some of the metal. As the pulse ends, the liquefied metal around the keyhole flows back in, solidifying and creating a small spot weld. This entire process just a few milliseconds.
Lasers can fire many pulses per second, and, by moving either the work piece or optics, allow either separate “spot” welds or a series of overlapping spot welds to create a laser seam weld that can be structurally sound and/or hermetic.
In some sheet metal applications that require resistance spot welding, an automated laser keyhole welding process can save time and improve weld quality. The process is well-suited for welding some dissimilar metals, which can be difficult to weld properly with resistance spot welding because of differences in the physical, chemical, and mechanical properties of the base metals.
Laser keyhole welding uses a powerful laser beam to weld two workpieces together. A high-energy-density laser hits a small pinpointed spot on the material. When light hits the top surface, it melts and vaporizes the metal. The pressure of the metal vapor pushes the liquid metal downward and aside, generating a keyhole. As the laser beam is moved across the surface, the keyhole follows the beam and creates a weld that is typically deep and narrow
In suitable applications, laser keyhole welding offers:
- Precise control of penetration depth, which eliminates any deformation or indentation on the back side of the bottom part. This reduces the time and money spent on postweld grinding or touchups.
- A very small beam size — less than 1 mm — that results in a small heat-affected zone. This offers benefits when welding thin materials or metals in which controlling heat input is important.
- An extremely fast process that is typically three to four times faster than manual resistance spot welding.
- Consistency and predictability, which result in high-quality finished welds and reduced time and money spent on rework.
Our WOBBLE-3 handheld laser welders
can join a wide range of steels, nickel alloys, titanium, aluminium and copper.
Width: 10 nm - 3000 nm
Depth: 10 nm - 5 mm
Range from 0 - 5 meter per second
Advantages of laser spot welding with our Wobble-3
The advantages of the laser technique, compared with arc or resistance welding processes are summarised as follows: