Electric resistance welding (ERW) refers to a group of welding

Welding

Welding is a fabrication or sculptural process that joins materials, usually metals or thermoplastics, by causing coalescence. This is often done by melting the workpieces and adding a filler material to form a pool of molten material that cools to become a strong joint, with pressure sometimes...

 processes such as spot and seam welding that produce coalescence of faying surfaces where heat to form the weld is generated by the electical reistance of material vs the time and the force used to hold the materials together during welding. Some factors influencing heat or welding temperatures are the proportions of the workpieces, the coating or the lack of coating, the electrode materials, electrode geometry, electrode pressing force, weld current and weld time.