Laser welding

Laser welding

All materials that can be welded conventionally are laser weldable. The quality and speed of laser welding performed by laser machines is far superior to conventional processes and much more economical. Depending on the power of the laser source used, the welding will be carried out by thermal conduction for small thicknesses or by keyhole (steam capillary) for large thicknesses which require high laser power. It is also possible to weld thermoplastics and composite materials by laser. Diode laser sources are most often used with wavelengths suited to the materials to be welded.

High power laser welding and thermal conduction laser welding

High power welding uses a high intensity laser source (several kilowatts) that allows welding of large thicknesses or multiple thicknesses. This process creates a vapor capillary through the thickness of the material which is maintained throughout the welding process. Laser welding in keyhole mode achieves a welding speed of several meters per minute with high weld quality.

Le soudage par conduction thermique est utilisé sur des épaisseurs plus faibles (1 à 2 mm). Seule la surface est fondue. Le cordon de soudure est en général plus lisse et présente moins de porosités. Ce procédé de soudage est le plus souvent utilisé lorsque les cordons de soudure sont apparents et que l’aspect esthétique de la pièce est un critère important (éviers, soufflet métalliques…).

Laser welding of plastic or composite parts

Principle of laser welding of thermoplastics.
The laser beam passes through the upper substrate which must be transparent to the laser wavelength, while the lower substrate is absorbent. The latter by thermal conduction will melt the upper substrate. During welding, the two parts to be assembled are subjected to mechanical pressure which keeps them in contact until the end of the process. The two substrates are thus welded by laser.

Many systems equip the automotive industry for the welding of many parts integrated in today's vehicles: pump, sensor, electronics, keys, headlights and also certain body parts…

The medical field is also a major user LPKF systems for the welding of numerous parts: various tubes, capsules, filters…

That laser welding of thermoplastics is a clean process, without chemical waste (no glue, no solvents), and without mechanical contact since it is the laser beam that melts the plastic and thus welds the parts together.

Application of laser welding of thermoplastics in the automotive industry

Application du soudage laser de thermoplastiques dans l’industrie aéronautique

Principe du drapage par laser à diode Laserline de pièces en fibre de carbone

Advantages of laser welding:

• A non-contact process that reduces the cost of tooling for maintaining parts.
• Welding intensity on a small diameter (laser spot size from a few microns to several millimeters).
• High speed and high precision of laser welding with limited heat input
• Welding of different materials, identical or dissimilar and of varying thicknesses Welding of parts with complex geometries (2D, 3D).
• Reduced implementation time.
• Suitable for any type of production: unit, small or large series.
• Modularity and choice of integrated equipment: XY table, Z axes, turntable, robot, etc. Integration of real-time control modules for the welding process (vision, Cmos camera, etc.).
• Remote control and handling during maintenance or training operations.