Abstract: A joining portion of a polymeric component, such as a vehicle door panel, may be welded (for example, a spot weld) to a metal component, such as a mating vehicle panel, using a molded-in-place metallic welding insert. The welding insert is shaped to provide welding surfaces at both surfaces of the joining portion of the plastic component and to conduct a welding current between the surfaces. When the workpieces are assembled for welding, opposing spot welding electrodes bear against the outer surfaces of the metal part and the metal insert in the plastic part. A spot welding operation produces a weld nugget between the facing surface of the metal part and the metal insert anchored in the plastic part. Continuous seam welds or a series of stitch seam welds may be made using suitably shaped welding inserts.

Abstract: A method is disclosed for laser welding two sheets of metal, the metal being of the type having associated gases tending to be trapped and expand in the weld zone during welding due to heat from the laser. These expanded gases tend to separate the upper and lower portions of the weld zone and/or expand through the weld zone toward the laser beam to create porosity in the final weld. Such metal may be coated, such as galvanized steel, in which case the zinc vaporizes into a gas in the weld zone between the adjacent sheets, or it may be poorly fitting sheets, in which case air is trapped in surface irregularities between the sheets. In either case, the method adds to the standard laser beam a surrounding stream of pressurized shield gas effective to create a pressure at the surface of the weld zone sufficient to force the molten metal of the two sheets together and force the expanded associated gases out of the weld zone in a direction away from the laser beam, whereby a non-porous weld may be created.