Laser Welding of AZ61 magnesium-based Alloys

Laser welding of AZ6 1 magnesium alloys was carried out using a CO2 laser welding experimental system. The welding properties of AZ61 sheets with different thickness were investigated. The effect of processing parameters including laser power, welding speed and protection gas flow was researched. The results show that laser power and welding speed have large effect on the weld width and joint dimensions. Protection gas flow has relatively slight effect on the weld width. The property test of three typical joints indicates that microhardness and tensile strength in weld zone are higher than that of AZ6 1 base metal. Joints with good appearance and excellent mechanical properties can be produced using CO2 laser welding method. The microstructure with small grains in weld zone is believed to be responsible for the excellent mechanical properties of AZ61 joints.