Weldability of thin sheet metals by small-scale resistance spot welding using high-frequency inverter and capacitor-discharge power supplies

An investigation has been conducted of the weldability of 0.2-mm-thick shee t aluminum, brass, and copper in small-scale resistance spot welding using a high-frequency inverter and a capacitor-discharge power supply. The resul ts have been compared to those of previous investigations using a line-freq uency alternating current power supply. The effects of electrode materials and process parameters on joint strength, nugget diameter, weld-metal expul sion and electrode-sheet sticking were studied. This work has also provided practical guidelines for selection of power supplies, process parameters ( welding current/pulse energy, welding time/pulse width, electrode forces, e tc.) and electrode materials for small-scale resistance spot welding of thi n sheet aluminum, brass and copper.