Oscillation mechanisms in the deep keyhole during CW CO2 laser welding

摘要

Abstract: The melt surface oscillations during the nonpenetrating cw CO$-2$/ laser welding of metals are studied. It is assumed that the concurrence between the melt expelling from the keyhole bottom by the vapor pressure and the capillary and the gravity forces tendency to fill the keyhole is the main cause of building up the oscillations. Assuming that the radiation flux being transported to the bottom is unstable, the possibility of parametric inducing melt oscillations on its bottom is investigated. !9