Electric fusion welding (EFW)is the combination of metal and metal by heating one or several consumable electrodes and the workpiece. Resistance welding is a welding process that uses a strong current to pass through the contact point between the electrode and the workpiece to generate heat from the contact resistance.
The arc of electric fusion welding melts the metal and the filling material fully, and does not need to pressurize, and the filling metal part comes from the electrode.
Electric resistance welding (ERW)is a type of welding method that uses resistance heat as an energy source, including electroslag welding that uses slag resistance heat as an energy source and resistance welding that uses solid resistance heat as an energy source.
Resistance welding often uses a large current. To prevent arcing on the contact surface and to forge the weld metal, pressure is always applied during the welding process.
Welding achieves the purpose of joining through the following three ways:
1. Fusion welding
The workpieces to be joined are heated to melt them locally to form a molten pool. After the molten pool is cooled and solidified, they are joined. If necessary, a filler can be added to assist. It is suitable for welding of various metals and alloys without pressure.
2. Pressure welding
The welding process must exert pressure on the weldment and belongs to the processing of various metal materials and some metal materials.
A metal material with a melting point lower than that of the base material is used as the brazing filler metal, and the liquid brazing material is used to wet the base material, fill the joint gap, and mutually diffuse with the base material to realize a link weldment. Suitable for welding processing of various materials, and also suitable for welding processing of different metals or different materials.
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