A study of fiber laser welding of galvanized steel using a suction method

In this paper, we describe a method employing a suction device adapted to provide a negative pressure zone on the surface of the keyhole to allow the highly-pressurized zinc vapor to escape. The microstructure and properties of the lap joint were studied, and the distribution of zinc element in the joints was analyzed using synchrotron radiation X-ray. A high-speed video camera was used to record the dynamic behavior of the laser-induced plasma plume and the zinc vapor. Experimental results demonstrated that this suction method can not only facilitate venting of the high pressure zinc vapor from the molten pool and the keyhole, but also stabilizes the laser-induced plasma plume during the welding process. A lap joint with a good surface quality and excellent mechanical strength was obtained using this method.