RWMA Copper Alloys

RWMA Class Type of Material CDA No. Primary Use
Class 1 Copper-Zirconium C15000

Zirconium Copper is used in spot welding electrodes and seam weld wheels. It is particularly useful when welding galvanized materials because of its high thermal conductivity, which prevents sticking.

Class 2 Copper-Chromium C18200

Chromium Copper is the primary copper alloy for high level production spot and seam welding of clean mild steel, low alloy steels, stainless steel, low conductivity brasses and bronzes, nickel-silver, nickel, nickel alloys, and monel. It is also suitable for projection welding dies, seam welder shafts and bearings, flash and butt welding dies, and current-carrying structural members.

Class 2 Copper-Chromium-Zirconium C18150

Chromium Zirconium Copper is used as an electrode material for welding galvanized steel and other metallic-coated materials. It has improved creep resistance at high operating temperatures.

Class 3 Copper-Nickel-Silicon-Chromium C18000

Class 3 Beryllium Free Copper is a very hard, heat-treatable copper with moderate electrical conductivity that is ideal for use as seam weld wheels, projection welding dies, flash and butt welding dies, current-carrying shafts and bushings, high stressed structural current-carrying members, electrode holders, and high pressure electrodes where the welded material has a high electrical resistance.

Class 3 Copper-Nickel-Beryllium C17510

Class 3 Beryllium Copper is heat-treatable with moderate electrical and thermal conductivity and high tensile strength. It is recommended for projection welding dies, flash and butt welding dies, current-carrying members, and heavy-duty offset electrode holders. It is also generally recommended for spot and steam welding steels with high electrical resistance, such as stainless steel.

Class 4 Copper-Beryllium C17200

Class 4 Beryllium Copper has extremely high hardness and tensile strength but less electrical conductivity than Class III alloys. It is recommended as the electrode material for special flash, upset-butt and projection welding applications where pressures are extremely high and wear is severe, but where heat is not excessive. They are used frequently in the form of inserts and facings and seam welding bushings.

C101 Oxygen-Free Copper C10100

Oxygen-Free Copper has the highest conductivity of all coppers. It is used for electrical and electronic conductors, wave guides, cavity resonators, super conductor matrixes, vacuum tube and solid-state devices, and glass to metal seals.

C110 Electrolytic Copper C11000

Electrolytic Copper's malleability allows it to be readily bent, soldered, drilled, welded, and formed to fit almost any design. It is primarally used for plumbing fitting and some electrical compenents that do not require extensive machining.