Synergetic effects of hybrid laser/arc welding

The present study reports the results of a study examining the synergetic effects of hybrid laser/arc welding. Experiments were carried out with a 500 W Nd:YAG laser in combination with standard gas tungsten arc welding equipment and attention was focused on two aspects: the heat transfer efficiency and the melting efficiency. The heat transfer efficiency was determined by calorimetric measurements, whereas the melting efficiency was obtained from the transverse cross-sections of welds produced under various conditions. In addition, analytic calculations of the melting efficiency were performed on the basis of a modified form of the Rosenthal equation. The results show that the interaction of the laser and the arc does not lead to a noticeable change in the heat transfer efficiency, but results in a significant increase in the melting efficiency. The observed synergic melting effect is caused by addition of the two heat sources (laser and arc) and the contraction of the arc by the laser beam.