The S-Class of Mercedes-Benz is generally regarded as a technological showpiece in automobile construction. The inner door frames produced by means of pressure die casting also correspond to this high-tech image. The single-part aluminium component improves the stability of the door and supports numerous other components and functions. It is produced in six variants by Georg Fischer Druckguss GmbH & Co KG. A unique feature is the upper part of the door frame, which consists of an extruded profile and is welded to the cast part. Studies on the welding suitability of pressure die casting reveal that metal inert-gas welding is most suitable.