Abstract
Microstructure, hardness and residual stresses of the laser beam overlap welds between AZ31B
sheets and AZ31, AZ61 and AZ80 extruded profiles are investigated using microscopy and X-ray
diffraction. The result of the investigations reveal that weld microstructure, the size of the HAZ,
precipitate density and the maximum compressive residual stress values depend strongly on the Al
content of the weld zone of two Mg-alloys.