Even with plastic products, the laser replaces classic connection technologies and thus achieves unmatched quality. It opens up completely new areas of use and markets due to its specific advantages.
New applications and material combinations
The plastic welding process shows its advantages when high requirements are set for welding and process reliability. The laser beam doesn’t touch the surface, can apply its energy in an exact amount and provides for absolutely sealed, visually flawless and particle-free weldings.
The welding process
For laser beams, two kinds of plastic can be used: laser-transparent and laser-absorbing. Most thermoplastics can be easily irradiated with typical laser wavelengths. But with additions in the plastic, they become absorbing. When the laser beam strikes an absorbing surface, its energy is transformed into heat.
With laser transmission welding, a material that is transparent for the laser wavelength lies over the absorber. A tensioning tool presses the join partners together. The laser irradiates the transparent element and puts the laser focus in the welding level.
The laser energy melts the surface of the absorbing material. Thermal conduction comes about through the joining pressure of the tensioning device; it plasticizes the contact surface of the transparent material. After re-hardening, the contact zone is reliably and lastingly welded.
Quality Assurance Measures
With laser welding of plastics, complex three-dimensional designs are no problem. The beam head itself does not touch the material at any point. Even areas difficult to access or thick layers are reliably bonded. In addition, new materials and varied combination possibilities are constantly being developed.
The quality assurance measures that can be integrated into the process are the basis for seamless tracking. They reduce the time and effort for testing and give quick indications as to sources of errors, e.g., changed material characteristics of blanks.
- Joining path monitoring – welding until reaching a defined settling. Joining path measurement in relation to welding time allows reliable inferences as to process quality.
- Pyrometer monitoring continuously determines temperature characteristics over the entire welded seam. The process detects gaps or particles in the welded seam through deviations from the target curve.
- An integrated transmission tester checks the transmission characteristics of the materials and components used before and during the welding process.
- By means of reflection diagnosis, which analyzes the light reflection on material layers, reliable statements can be made about the quality of the welded seam.
Services of LaserMicronics - More than just custom manufacturing
At the Fürth production location, extremely demanding components can be efficiently manufactured at a high level of quality with our competent employees from the areas of process development and production.
As one of the first users of this innovative joining technology, LaserMicronics has extensive experience with materials, tools, applications and layout. Together with the customer, LaserMicronics develops innovative and practically oriented approaches and implements them both in small and in large series production. If needed, there is a clean room available.
Laser welding of plastics with LaserMicronics
- Reliable, cost-effective and hygienic joining process
- Competent advise on laser welding, prototyping, small and large series production for an optimal product layout
- High level of flexibility
- Reliable quality monitoring in the welding process
- Extensive experience with products for the electronics, automotive and medical industries