Investigation of the efficiency process during CO2 laser welding of low-alloyed steels

This paper reports results from the theoretical and experimental study of the energy transfer during CO2 laser beam welding of 10 mm low-alloyed steels square butt joints. The laser beam power and the welding speed are varied systematically from 9 kW to 32 kW and from 1 m/min to 5 m/min, respectively. The observed weld depth penetration is up to 10 mm and the width of weld seams is between 0.8 and 1.25 mm. The joining efficiency during the laser welding was in the range of 11.8 to 32 mm(2)/kJ. Melting efficiency is determined from the measured welding seams cross section for a specified laser power and travel speed. Theoretically, predicted values of melting efficiency are calculated using Rosenthal's and Rycalin moving heat sources equation in 2D (line source).