Abstract: A stud for joining onto a flat workpiece, in particular for the purpose of stud welding. The stud including a joining portion, by means of which the joining component can be joined onto the workpiece, and a fastening portion, formed as a single piece with the joining portion and to which at least one further structural element can be fastened. The joining portion including a joining surface that contacts the flat workpiece during joining and has a circumference. There being realized in the joining surface at least one recess that extends transversely relative to the circumference and that divides the joining surface into at least two partial surfaces.

Abstract: The present invention relates to a lift-and-strike welding process. In a first step, e.g. an aluminum surfaces (5) of a component is cleaned by striking an arc and then the element (4) to be connected is welded on by means of at least one second voltage. Besides a lift-and-strike welding apparatus, a further lift-and-strike welding process is also provided, wherein an electric cleaning current flows between a surface (5) of a component and an element to be welded thereon, in that the component rests on the surface (5) and then the element (4) is lifted off the surface (5) up to an approximately, in terms of time, constant distance for removing a coating from the surface (5) by means of an arc, then the current changes its polarity, wherein afterwards at least one welding current is produced and then the element (4) is welded to the surface (5).