Flanged Capacitor Discharge studs are used with thin materials to eliminate discoloration and marring to the reverse side of the material. Capacitor Discharge welding uses short weld cycles and are commonly used for mild steel, stainless steel and aluminum applications. Capacitor Discharge (CD) Stud Welding is also a semi-automatic arc welding process. However, with CD welding small diameter fasteners (1/4? and under) are end welded to extremely thin gauge parent metal. The CD process operates on the principle of capacitor stored energy which is instantaneously discharged by the equipment system through a special weld timing tip. Since the entire weld cycle is completed in several milliseconds, welds can be made to thin sheet without pronounced distortion, burn-through or discoloration. CD welding permits stud welding of dissimilar metals.