Diode laser brazing – the technique
Joining methods, in which the brazing solder is melted with the help of an industrial laser, have been used mainly in the mass production of vehicle bodies. There, laser beam brazing is mostly used for joining galvanized metal sheets or lightweight components made of aluminum, but also for other brazing material. Laser automobile brazing is usually realized with a brazing optic that is integrated in a robot. The laser beam is guided along the joint where it melts the brazing solder – e.g. a copper-silicon-wire – and in so doing connects the components. The success of the brazing process is based on whether the firmness is similar to the welding seams and the high esthetic quality of the joints: brazing seams that were generated with lasers are known for their sealed, smooth and clean structures. This is visually attractive and reduces post-processing to a minimum. Car body construction, for example, can often be lacquered immediately after cleaning.
Brazing process advantages of a diode laser
In the field of laser brazing, the global practical usage of Laserline's diode lasers has been established. More than 800 LDF diode lasers are in permanent use successfully in different brazing applications within the automotive body assembly worldwide. Besides the requested higher firmness and a possibly small heat-affected zone, for these visible seams in particular, high demands are made on the appearance of the joint. A key process advantage of diode lasers is the striking calm molten pools.
Furthermore, the multi-spot-module developed by Laserline has achieved enormous process advantages during brazing with triple spot. At the often difficult brazing of hot-galvanized sheets, this technology can achieve, as usual, high brazing seam qualities without process speed reduction.