Copper Alloys
RWMA Copper Alloys
| Material CDA # | RWMA Class | Composition | Density gr/cc | Density lb/in3 | Rockwell Hardness | Thermal Conductivity | Electrical Conductivity | Ultimate Tensile Strength | 0.2% Yield Strength |
|---|---|---|---|---|---|---|---|---|---|
| Note: “typical” values listed – Not Material Specifications | www.resistanceweldsupplies.com | ||||||||
| C11000 | --- | Pure Copper | 8.94 | 0.323 | 34 F | 229 Btu / hr.ft.F | 100% IACS | 40,000 psi | --- |
| C15000 | 1 | Cu / Zr | 8.89 | 0.321 | 70 B | 212 Btu / hr.ft.F | 90% IACS | 66,000 psi | 56,000 psi |
| C16200 | 1 | Cu / Cd | 8.89 | 0.321 | 70 B | 198 Btu / hr.ft.F | 90% IACS | 65,000 psi | 54,000 psi |
| C18200 | 2 | Cu / Cr | 8.89 | 0.321 | 83 B | 187 Btu / hr.ft.F | 85% IACS | 75,000 psi | 70,000 psi |
| C18150 | 2 | Cu / Cr / Zr | 8.89 | 0.321 | 82 B | 187 Btu / hr.ft.F | 74% IACS | 81,000 psi | 72,000 psi |
| C18000 | 3 | Cu / Ni / Si / Cr | 8.71 | 0.315 | 94 B | 125 Btu / hr.ft.F | 48% IACS | 100,000 psi | 75,000 psi |
| C17510 | 3 | Cu / Ni / Be | 8.75 | 0.316 | 100 B | 113 Btu / hr.ft.F | 48% IACS | 110,000 psi | 95,000 psi |
| C17200 | 4 | Cu / Be | 8.25 | 0.298 | 38 C | 75 Btu / hr.ft.F | 22% IACS | 170,000 psi | 150,000 psi |
| C15725 | 20 | Cu / AL₂O₃ | 8.86 | 0.32 | 73 B | 199 Btu / hr.ft.F | 87% IACS | 75,000 psi | 69,000 psi |
| C15760 | 20 | Cu / AL₂O₃ | 8.81 | 0.318 | 82 B | 186 Btu / hr.ft.F | 78% IACS | 83,000 psi | 79,000 psi |
RWMA Class 1
ZIRCONIUM-COPPER, suited to welding aluminum & magnesium alloys, coated materials, and brass & bronze.
Class 1: alloy is superior to pure copper as an electrode material and is recommended as a general-purpose material for resistance welding use. It may be used for spot welding electrodes, seam welding wheels and welding fixture components. It is not heat treatable.
Also Known as: Tuffaloy 88, CMW 28, CuZr, and CuCd.
RWMA Class 2
CHROMIUM-COPPER, suited to welding cold- and hot-rolled steels, stainless steel, and low conductivity brasses and bronzes.
Class 2: alloy is a superior resistance welding electrode material, recommended for high-production operations. It's used for welding electrodes, projection welding dies, seam welding shafts and bearings, flash and butt welding dies, and current-carrying structural components. Available in forms for use as welding gun arms, welding platens and secondary-circuit structural members. It is heat treatable.
ZIRCONIUM-CHROMIUM-COPPER is suited to welding galvanized steel & other metallic-coated steel. This is a specially heat-treated alloy, which meets the minimum electrical conductivity and hardness specifications of Class 2 alloy.
Also Known as: CMW 3, CMW 328, Mallory 3, Tuffaloy 77, and Tuffaloy Z, CuCr, and CuCrZr.
RWMA Class 3
BERYLLIUM-NICKEL-COPPER and NICKEL-COPPER are suited to welding steels having high electrical resistance, such as stainless steel.
Class 3: alloy is recommended for projection welding dies, and flash and butt-welding dies. With its higher strength it is also used on highly current-carrying parts such as electrode shanks and heavy-duty electrode holders. It is heat treatable.
Also Known as: CMW 100, CMW 353, Mallory 100, Tuffaloy 55, Tuffaloy 55A, CuNiSiCr, and CuNiBe.
RWMA Class 4
BERYLLIUM-COPPER has extremely high hardness, and is recommended for projection, flash and butt-welding dies. It has lower conductivity than Class 3 alloy but it is harder and more wear resistant. It should be considered where there is concern with high-pressure density and severe wear, but where heating, due to its low conductivity, is no excessive.
It is used frequently in the form of inserts, die facings, and seam welder bushings. It is available in the annealed condition, which is more readily machined, and then subsequently heat-treated.
Also Known as: Tuffaloy 44, CMW 73, and CuBe.
RWMA Class 20
COPPER-ALUMINUM OXIDE has exceptional resistance to deformation when welding and it is highly recommended for weld caps when welding coated and galvanized steels. It allows a stable start-up and generally outlasts other cap material when welding parameters are not carefully controlled.
Also Known as: Elkaloy 20 and CuAL₂O₃
Rectangular Bar - Class 1, 2, & 3
| SIZE | WEIGHT |
|---|---|
| 1/4" x 1/2" | 0.48 LBS/FT |
| 1/4" x 3/4" | 0.73 LBS/FT |
| 1/4" x 1" | 0.96 LBS/FT |
| 1/4" x 1 1/4" | 1.20 LBS/FT |
| 1/4" x 1 1/2" | 1.44 LBS/FT |
| 1/4" x 2" | 1.92 LBS/FT |
| 3/8" x 5/8" | 0.90 LBS/FT |
| 3/8" x 3/4" | 1.08 LBS/FT |
| 3/8" x 1" | 1.44 LBS/FT |
| 3/8" x 1 1/2" | 2.16 LBS/FT |
| 3/8" x 2" | 2.88 LBS/FT |
| 1/2" x 3/4" | 1.44 LBS/FT |
| 1/2" x 1" | 1.92 LBS/FT |
| 1/2" x 1 1/4" | 2.40 LBS/FT |
| 1/2" x 1 1/2" | 2.88 LBS/FT |
| 1/2" x 2" | 3.84 LBS/FT |
| 1/2" x 2 1/2" | 4.83 LBS/FT |
| 1/2" x 3" | 5.81 LBS/FT |
| 5/8" x 3/4" | 1.80 LBS/FT |
| 5/8" x 1" | 2.40 LBS/FT |
| 5/8" x 1 1/2" | 3.60 LBS/FT |
| 5/8" x 2" | 4.85 LBS/FT |
| 5/8" x 3" | 7.27 LBS/FT |
| 5/8" x 4" | 9.60 LBS/FT |
| 3/4" x 1" | 2.88 LBS/FT |
| 3/4" x 1 1/4" | 3.64 LBS/FT |
| 3/4" x 1 1/2" | 4.32 LBS/FT |
| 3/4" x 2" | 5.72 LBS/FT |
| 3/4" x 2 1/4" | 6.48 LBS/FT |
| 3/4" x 2 1/2" | 7.20 LBS/FT |
| 3/4" x 3" | 8.64 LBS/FT |
| 1" x 1 1/4" | 4.85 LBS/FT |
| 1" x 1 1/2" | 5.76 LBS/FT |
| 1" x 2" | 7.68 LBS/FT |
| 1" x 2 1/2" | 9.70 LBS/FT |
| 1" x 2 3/4" | 10.56 LBS/FT |
| 1" x 3" | 11.55 LBS/FT |
| 1 1/4" x 1 1/2" | 7.25 LBS/FT |
| 1 1/4" x 1 3/4" | 8.40 LBS/FT |
| 1 1/4" x 2" | 9.60 LBS/FT |
| 1 1/4" x 2 1/2" | 12.06 LBS/FT |
| 1 1/2" x 1 3/4" | 10.09 LBS/FT |
| 1 1/2" x 2" | 11.60 LBS/FT |
| 1 1/2" x 3" | 17.28 LBS/FT |
| 2" x 3 1/4" | 25.15 LBS/FT |
| 2" x 3 3/4" | 29.05 LBS/FT |
Round Bar - Class 1, 2, & 3
| SIZE | WEIGHT |
|---|---|
| 1/8" | 0.05 LBS/FT |
| 3/16" | 0.11 LBS/FT |
| 1/4" | 0.19 LBS/FT |
| 5/16" | 0.30 LBS/FT |
| 3/8" | 0.43 LBS/FT |
| 1/2" | 0.76 LBS/FT |
| 9/16" | 0.96 LBS/FT |
| 5/8" | 1.18 LBS/FT |
| 3/4" | 1.70 LBS/FT |
| 7/8" | 2.32 LBS/FT |
| 1" | 3.03 LBS/FT |
| 1 1/8" | 3.84 LBS/FT |
| 1 1/4" | 4.74 LBS/FT |
| 1 3/8" | 5.74 LBS/FT |
| 1 1/2" | 6.82 LBS/FT |
| 1 5/8" | 7.97 LBS/FT |
| 1 3/4" | 9.28 LBS/FT |
| 2" | 12.12 LBS/FT |
| 2 1/8" | 13.62 LBS/FT |
| 2 1/4" | 15.4 LBS/FT |
| 2 1/2" | 18.97 LBS/FT |
| 2 3/4" | 23.00 LBS/FT |
| 3" | 27.15 LBS/FT |
| 3 1/4" | 32.05 LBS/FT |
| 3 1/2" | 37.18 LBS/FT |
Hex Bar - Class 1, 2, & 3
| SIZE | WEIGHT |
|---|---|
| 3/8" | 0.47 LBS/FT |
| 1/2" | 0.85 LBS/FT |
| 5/8" | 1.31 LBS/FT |
| 3/4" | 2.18 LBS/FT |
| 7/8" | 2.56 LBS/FT |
| 1" | 3.35 LBS/FT |
| 1 1/8" | 4.24 LBS/FT |
| 1 1/4" | 5.25 LBS/FT |
| 1 1/2" | 7.55 LBS/FT |
Square Bar - Class 1, 2, & 3
| SIZE | WEIGHT |
|---|---|
| 1/4" x 1/4" | 0.24 LBS/FT |
| 3/8" x 3/8" | 0.54 LBS/FT |
| 1/2" x 1/2" | 0.96 LBS/FT |
| 5/8" x 5/8" | 1.56 LBS/FT |
| 3/4" x 3/4" | 2.16 LBS/FT |
| 1" x 1" | 3.84 LBS/FT |
| 1 1/4" x 1 1/4" | 6.00 LBS/FT |
| 1 1/2" x 1 1/2" | 8.64 LBS/FT |
| 1 3/4" x 1 3/4" | 11.83 LBS/FT |
| 2" x 2" | 15.46 LBS/FT |
