Resistance brazing is not spot welding so the electrode face geometry does not have to concentrate the heat into a small area. Frequently the electrode face is machined to conform to the surface that it is in contact with. Frequently the electrode will contact the entire work piece surface. In some cases the electrode faces is milled out. The work piece is nested into the face of the electrode in order to insure proper part placement and alignment. A small vacuum is sometimes pulled through the center of the electrode to hold the part in place before the electrode closes. This is very common for small part brazing.
The electrode material is frequently RWMA Class 2. It could be ETP copper and in many cases carbon electrodes are used.
When resistance brazing contact materials, refractory faced electrodes RWMA Class 11, 13 and 14 as well as Class 2 are commonly used.
Group C material is a designation of the Resistance Welding Manufacturers Alliance (RWMA). It describes a group of Specialty materials with high strength and high electrical conductivity. Their properties make them excellent materials to use in the resistance welding industry as electrodes especially for galvanized steel.
Group B materials is a designation of the Resistance Welding Manufacturers Alliance (RWMA). It describes a group of Tungsten/Copper materials with high strength and good electrical conductivity. Their main feature is high strength at high temperatures. Their properties make them excellent materials to use in the resistance welding industry as electrodes at high heat and forces.
Group A material is a designation of the Resistance Welding Manufacturers Alliance (RWMA). It describes a group of copper alloys with high strength and high electrical conductivity. Their properties make them excellent materials to use in the resistance welding industry as electrodes and current carrying componenets used in the machinery of the resistance welding industry.
Class 11 material is a designation of the Resistance Welding Manufacturers Alliance (RWMA). It describes a Tungsten/Copper base material with good conductivity and excellent strength at high temperatures and forces. Class 11 is often used as a back up electrode for projection welding.
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