1. Understanding the constraints of laser technology

1.1 How does laser welding work?

Thermoplastic welding, and more generally the assembly of parts with thermoplastics, is based, whatever the technology used, on the heating of at least one polymer. The temperature reached must be close to the melting point of the polymers to be joined, and of all materials compatible with each other (see ">What phenomena are involved in joining?" data sheet).

With pressure, the polymer in its liquid or pasty state expels the air between the thicknesses of the parts to be joined, and if all conditions are met, cooling will freeze this state: we'll then say that you've glued or assembled your parts for a certain lifespan.

The laser beam is an energy that excites the molecules of a material thanks to...