Resistance soldering differs from resistance welding in that it uses an additive called solder. It is a thermal process whereby a material bond is produced by melting a solder and diffusing at the interfaces. The temperatures used depend on the solder used. The melting temperature of the base materials is not reached as a result.
Resistance soldering is based on the resistance spot welding method where times are adapted to suit the properties of the material to be welded.