The basic process of laser plastic welding is seam welding. During this process, the laser beam penetrates the workpiece, which is to be joined and is positioned on top, and is then absorbed by the piece, which is positioned at the bottom.
The heat leads to plasticization, which results in the bridging of the gap in the workpiece. As heat is conducted, the workpiece, which is positioned on top, is heated up. This means that the smallest possible gap in the workpiece is a determining factor for the application's success since the gap acts as a heat barrier.
Working principle of laser absorption welding (see the illustration on the right):
The laser light penetrates the upper layers and is absorbed by the lower piece that is to be joined (A). As the lower piece heats up (B), heat is conducted to the upper piece (C).
The shared molten area solidifies under pressure that is applied externally, thereby creating a high-quality weld connection (D).
What can be welded?
Success in laser plastic welding depends on a number of factors. One is the choice of material. Normally, plastics of the same composition can be joined to each other. Different plastics can also be joined, provided that they are chemically and physically compatible and that their melting temperature ranges overlap sufficiently.
Using the correct laser source is another important factor. Finally, successful welding also depends on the design of both the part and processing machine, which must exert sufficient pressure on the materials that are to be joined. A trial setup is the quickest way to find out what will work. Please contact us with your queries at any time.