Absorption in the keyhole Available to Purchase

The absorption of the laser energy in the keyhole is a function of the laser frequency (or wavelength), the chemistry of the material being welded and the temperature of the vapor. The absorption greatly affects the shape of the fusion zone as well as the integrity and efficiency of the laser welding process. In this paper absorption is assumed to be by an inverse Bremsstralung process, i. e. the photons are absorbed by the electrons in the vapor. The inverse absorption is a function of the density of states of the alloying elements and the frequency of the laser radiation. This coefficient is calculated for both CO₂ and Nd:YAG laser radiation for both iron and aluminum. The appropriate equations for the calculations are stated and the results for iron and aluminum are depicted. The difference in the Bremsstrahlung absorption between CO₂ and Nd:YAG laser radiation is illustrated in a series of graphs.