The influence of process parameters on porosity formation in hybrid LASER-GMA welding of AA6082 aluminum alloy

This paper deals with an experimental campaign carried out on AA6082 8 mm thick plates in order to investigate the role of process parameters on porosity formation in hybrid LASER-GMA welding. Bead on plate weldments were obtained on the above mentioned aluminum alloy considering the variation of the following process parameters: GMAW current (120 and 180 A for short-arc mode, 90 and 130 A for pulsed-arc mode), arc transfer mode (short-arc and pulsed-arc) and mutual distance between arc and LASER sources (0, 3 and 6 mm). Porosities occurring in the fused zone were observed by means of X-ray inspection and measured exploiting an image analysis software. In order to understand the possible correlation between process parameters and porosity formation an analysis of variance statistical approach was exploited. The obtained results pointed out that GMAW current is significant on porosity formation, while the distance between the sources do not affect this aspect.

► This paper deals with experimental trials concerning hybrid LASER-GMA welding.
► The role of process parameters on porosity formation in the weld bead is investigated.
► Porosity detection and measurement are performed by means of x-ray inspection and image analysis.
► The actual influence of process parameters on porosity formation is evaluated by means of ANOVA.
► Welding current is a significant parameter.