General Use and Description of RWMA Group A Copper Alloys

Alloy Physical Properties

Copper Alloys General Use and Description - RWMA

RWMA CLASS 1 RWMA NO. RWMA GENERAL USE * RWMA DESCRIPTION CADI COMPANY INFORMATION
COPPER ZIRCONIUM C15000 Electrodes for welding aluminum alloys, magnesium alloys, coated materials, brass and bronzes. Can be used for both spot and seam welding. A specially heat-treated zirconium copper alloy that meets the minimum electrical conductivity and hardness specifications of class 1 alloy. A small addition of Zr to copper improves resistance to softening and resists deformation at high temperatures where normal copper would soften rapidly. Zirconium Copper is used as a class 1 electrode material to minimize sticking when resistance spot welding galvanized materials. Zirconium Copper is also used in many high temperature applications i.e. aerospace, power generation, etc.
RWMA CLASS 2 RWMA NO. RWMA GENERAL USE * RWMA DESCRIPTION CADI COMPANY INFORMATION
COPPER CHROMIUM -ZIRCONIUM C18150 These materials are stronger than Class 1 materials, have slightly lower conductivity. They are used for spot and seam welding of cold and hot rolled steel, stainless steel and low conductivity brass and bronze. They are also used as flash welding dies, and as electrodes for the welding of galvanized steel and other coated materials. A specially heat-treated chromium-zirconium copper alloy that meets the minimum electrical and hardness specifications of Class 2 alloys. Should be used in heat-treated condition. Zirconium addition to chromium copper improves creep resistance at high operating temperatures and reportedly reduces sticking of electrodes to the work during spot welding of galvanized materials. C18150 is specified mainly for electrode application.
COPPER CHROMIUM C18200 A high conductivity chromium copper alloy that obtains its optimum properties from a combination of both heat treatment and cold work. Should be used in heat-treated condition. Chromium copper is the primary copper alloy used for resistance spot and seam welding. This alloy achieves good hardness and electrical conductivity through a combination of heat-treatment and cold work. C18200 is utilized for electrodes, holders, adaptors, as well as numerous electrical applications where resistance to deformation at high temperature is required or when higher mechanical properties than C11000 are required.
RWMA CLASS 3 RWMA NO. RWMA GENERAL USE * RWMA DESCRIPTION CADI COMPANY INFORMATION
COPPER NICKEL—SILICON—CHROMIUM C18000 Their high hardness makes them ideal for electrodes for spot and seam welding of high resistance materials such as stainless steels, nichrome, inconel, and monel metal. As a casting, they are used for flash, butt and projection welding electrodes and fixtures. Other uses are welding gun components, seam welding bearing and other current carrying structural parts. Heat treatable copper alloys with a combination of high tensile strength and good electrical and thermal properties. Should be used in heat—treated condition. A very hard heat treatable copper with moderate electrical conductivity. C18000 is utilized when a combination of very good mechanical strength along with moderate electrical and thermal conductivity are required. C18000 offers excellent value for the properties it offers. C18000 is a viable substitute for C17500 and C17510 in many applications. Specify Cadi MOLD-MOR-1 for mold applications.
COPPER NICKEL—BERYLLIUM C17510 Heat treatable copper alloys with a combination of high tensile strength and good electrical and thermal properties. Should be used in heat—treated condition. A very hard heat treatable beryllium-copper with moderate electrical conductivity. C17510 can be utilized when a combination of very good mechanical strength along with moderate electrical and thermal conductivity are required. Specify Cadi MOLD-MOR –2 for mold applications.
RWMA CLASS 4 RWMA NO. RWMA GENERAL USE * RWMA DESCRIPTION CADI COMPANY INFORMATION
COPPER BERYLLIUM C17200 Electrode material for 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. They may also be used for seam welding bushings. Heat treatable copper alloy having the unusual combination of very high hardness, high strength and lower electrical conductivity than Class 3 materials. Should be used in heat-treated condition. The hardest and highest strength copper alloy, Beryllium copper is specified when the mechanical strength is the limiting design feature for a copper alloy. Specify Cadi MOLD-MOR-3 or 4 for mold applications.

 

* General suggested applications, not to be interpreted as the optimum for any specific application.
   RWMA Table 1.8.1