Laser welding study under vacuum conditions was performed. Plasma parameters (particulary electronic density and temperature) were measured. They were correlated to the molten pool analysis, and give informations on the energy deposition process inside the keyhole.
"CO2 laser welding process in reduced-pressure atmosphere", Proc. SPIE 2097, Laser Applications, (10 August 1994); doi: 10.1117/12.183134; https://doi.org/10.1117/12.183134