Joining processes
Capacitor discharge welding (CDW), welding with medium frequency direct current (MFDC) and alternating current (AC) are conductive resistance pressure welding processes. The substance-to-substance bond between the joined components arises due to the simultaneous application of force and heat. The heat required for this arises inside the joining components due to an electric current flow, which leads to resistance heating of the welding zone. A sufficiently high current concentration is attained with projection welding through a joining partner component with a hump-like contour. In contrast, with spot welding the necessary current concentration is realised through the geometry of the electrode tip.