Laser Welding of Polymers
Flexible Method for High Strength Connections with Perfect Surfaces
With the commonly used overlap welding method, the joint is completely inside the welded part. Pigments provide for the absorption of the laser energy in the IR range. Compared to conventional joining methods such as bonding, ultrasonic, vibration or hot plate welding, laser polymer welding features some process-related benefits.
Bonding of plastics mostly requires surface pre-treatment of the surfaces and needs organic solvents. Hot plate or hot air welding is cost-efficient, but slow and subject to wear. A large surface of the workpiece is heated up what is disadvantageous for sensitive components. Friction, ultrasonic or vibration welding expose workpieces to high mechanical load and therefore require a complex design and regular maintenance of the machines. Laser polymer welding, howecer, means low thermal and mechanical load to the component, this procedure is clean, there are no particles nor solvents and is highly flexible.
Diode lasers are the ideal choice for plastic welding. With different wavelengths ranging from 808 to 1470 nm they provide the best foundation for welding workpieces of any color. In the quasi simultaneous welding application any welding contours can be realized with the help of scanner heard. The usage of closed loop welding temperature controls allows great process safety and control. . The mechanical and thermal load of the layers is low so that sensitive electronics are not damaged. Main applications for laser welding of plastics are the automotive engineering, electronics, communications, medical device technology, human care and consumer products.
- During the transmitting welding the laser beam is transmitted by the first join partner and absorbed by the second join partner. Because of different pigment additions today plastics can be welded highly tensile in diverse color combinations.
Laser Polymer Welding in the Automotive Industry
- The top cover that is transparent for the laser beam is welded pressurized onto a black basic body that absorbs the laser beam in the infrared wavelength range.
Laser Polymer Welding – Housings for Electronics
- In the quasi simultaneous welding application any welding contours can be realized with the help of scanner heard. The usage of closed loop welding temperature controls allows great process safety and control.