Resistance Welding is a thermo-electric process where heat is generated at the interface of the parts to be joined by passing an electrical current through them or a precisely controlled time and under a controlled pressure (also called force). The name “resistance” spot welding derives from the fact that the resistance of the workpieces and electrodes are used in combination or contrast to generate the heat at their interface.
Key advantages of the resistance welding process include:
- Very short process time
- No consumables, such as brazing materials, solder, or welding rods
- Operator safety because of low voltage
- Clean and environmentally friendly
- A reliable electro-mechanical joint is formed
Resistance spot welding is a fairly simple heat generation process: the passage of current through a resistance generates heat. In addition to the bulk resistances, the contact resistances also play a major role. The contact resistances are influenced by the surface condition (surface roughness, cleanliness, oxidation, and plating’s).
The materials that can be welded by this process include low alloy and mild steel, stainless steel, Aluminium and light-alloys, nickel and its alloys, galvanized sheets, brass and copper