Gentle energy input - no forming fluff - exact reproducibility
At the laser beam-transmission welding, a laser transparent and laser absorbing component are always merged. Prior to being welded, the join partners are positioned and then pressed together. In the actual fusion process, the laser beam gets through the transparent component without significantly heating it up. But now, the absorbing component takes the laser energy so that it is heated at the surface. This energy is transferred via heat conduction onto the surface of the transparent component. And because of the existing joining pressure, a substance-to-substance bond is the end result for both parts.
The process advantages of the diode lasers
Because of the diode laser’s local energy input, the plastic is heated very quickly and gently to the material in the joint zone, resulting in a homogeneous melt without forming fluff by dry friction. Setting path- or temperature-monitoring systems can record the welding process and transfer the result to a higher-level control system. Functional changes at the component or new design ideas for the welding contour can be programmed flexibly. The laser protects particularly inside-lying and vibration-sensitive components or complex electrodes from damage by the contact-free heat input. The even energy distribution in the laser focus melts the welded joint without overheating the material and prevents pore formation.
Lightweight construction automobile tailgates out of plastic are produced via laser beam-transmission welding with diode lasers. The special feature: the welding seams are not visible, and so rework in the inner field of vision becomes completely obsolete.