That is a good question. We have not tried to weld thermoplastics using our CO2 Lasers. It is possible since the laser outputs a heat source and at the right intensity and speed, the thermoplastic can be heated and melted rather than instantaneously vaporized and off gassed. I have done research to see if CO2 laser can weld thermoplastics with positive results.
Our CO2 lasers are typical of other laser cutters on the market, so if their literature, or examples you have found, successfully weld thermoplastics, then ours will probably be able to as well.
In some cutting test with different speeds and intensities, the kerf has welded back together; however, this was caused by an unintentional process rather than an intentional one.
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Can a CO2 CNC laser machine be used for welding of thermoplastic materials?