The influence of different volume ratios of He and Ar in shielding gas mixture on the power waste parameters for Nd:YAG and CO2 laser welding

In this paper, we numerically solve the Saha equations to drive the number densities of electrons and ions, the degrees of ionization of the plasma as well as the refractive indices and the inverse Bremsstrahlung absorption coefficients as a function of temperature for a variety of volume ratios of the (He+Ar) mixtures. Furthermore, the heat transfer equation was solved to determine the plasma temperature. The effect of shielding gas volume ratios on the power waste parameters was estimated during long pulse Nd:YAG and CW CO2 laser welding accompanying the experimental verification. (C) 2013 Elsevier Ltd. All rights reserved.