Effects of Welding Parameters Onto Keyhole Geometry for Partial Penetration Laser Welding

The material and parameters like welding speed and laser beam parameters define the geometry of the keyhole. The keyhole geometry affects the weld geometry, such as width and depth, and in some cases it should be considered when selecting welding parameters. In-situ X-ray videography makes it possible to obtain time-and space resolved information about the keyhole geometry during the welding process. This paper describes the partial penetration laser welding experiments and shows the effects of a welding speed and a focal point position change onto some geometry values of the keyhole. Two different joint types were used, bead on plate to simulate a very good machined joint preparation and laser cut I-butt joint.