Examination of the process efficiency during hybrid laser-arc welding

Hybrid Laser Arc Welding (HLAW) is an increasingly accepted technology for a variety of commercial applications, from industries as diverse as shipbuilding to automobile manufacture. As applications become more widespread, there is a growing need to understand the relationship between the process parameters and resulting characteristics, such as mode of metal transfer, weld quality, microstructure, and distortion. Exploration of the arc and laser beam interaction is necessary to achieve a deeper understanding of the hybrid process. Measuring the heat input provides a means of quantifying this interaction. A calorimeter was used to measure the heat input during hybrid and conventional laser beam and gas metal arc welding processes. The mode of metal transfer is deduced from high speed imaging of the laser-arc interaction zone during processing. The results are presented in terms of process efficiency for hybrid, conventional laser beam, and GMA welding.