Abstract: The invention relates to a camshaft made of cast steel having an inner cavity with a cylindrical inner shape, especially a profiled cylindrical inner shape produced rationally according to a lost-foam casting method known per se. A steel camshaft thus produced exhibits a long service life and can withstand extremely high hertzian surface pressures on its bearing surfaces without any damages.

Abstract: In resistance forge welding, the heat for the welding point is produced by simultaneous action of an electrical current and the force of the electrode as well as the electrical resistance of the materials to be welded in the region of the point of contact of the electrodes. The workpieces generally lie flat on each other and are welded under considerable pressure at individual points by the force of the electrode. The current and the electrode force are supplied via the electrodes.In order to increase the controllability and dynamics of the electrode movement, according to the invention a controllable electromotive drive (13), which has a drive spindle (16) or a toothed rack, is used.