A welding auxiliary joining part in the form of a bolt having a head, a shank and a tip is disclosed. The welding auxiliary joining part is driven with the aid of a mechanical thermal setting method into a component made of non-weldable or poorly weldable material. During the driving-in operation, a welding head arises on account of mechanical deformation, such that subsequently the component can be connected via the welding auxiliary joining part to a further component made of weldable material by means of welding.