Laser Plastics Welding

The principle: Transparent and Absorbent Thermoplastics

Laser welding relies on two types of polymers, transparent or absorbent. Most thermoplastics in their natural state are transparent at typical laser wavelengths. Additives, such as carbon, in the plastic change the properties so that they become absorbent. The absorbing surface converts the laser energy into heat. In the transmission laser welding technique, a material transparent to the laser wavelength lies on top of an absorbent material. A clamping tool presses together the parts to be joined.

The laser beam penetrates through the transparent component with minor energy loss and melts the surface of the absorbing material. Heat transfers through conduction to plasticize the adjacent surface of the transparent material. This process is precisely controlled and continuously monitored during laser welding to ensure a repeatable quality weld. After resolidification, the two parts at the joint have been reliably and cohesively bonded.

Reliable Clamping Technology

A defined pressure joins the materials together during the laser welding process. It is therefore essential that the technology works with complete reliabilty. Uniform clamping is vital for high process quality. Pressing the parts together is crucial for effective thermal transfer.

From Ideas to Products

Narrow laser beams for a glowing future. Modern laser plastic welding boasts numerous benefits and goes well beyond the limits of traditional joining methods. Thanks to its specific advantages, it opens up completely new applications and markets.

New Applications and Material Combinations

High joint quality criteria bring the economic advantages of laser plastic welding into the spotlight. No other method simultaneously combines such a high degree of safety,  leanliness and speed – opening up completely new opportunities! Laser plastic welding can easily handle complex threedimensional designs. The beam head itself never touches the material.

Even poorly accessible zones or thick layers can be safely joined. Other convincing features are the continuous development of new materials and a wide range of combination options. The process is so gentle, the LPKF-Systems are ideal for components with sensitive surfaces.