Copper Alloys Find an Ideal Niche

Created at : Feb 28, 2024

Copper Alloys Find an Ideal Niche    

Pure copper is the most practical electrical conductor but lacks the toughness and durability for many industrial applications. By adding other metals to copper it creates alloys that resolve this issue. Four classes of RWMA copper alloys each have distinct properties and are becoming increasingly mainstream in manufacturing for many applications because of their outstanding performance. 

Four Important RWMA* classes are: 

Class 1:

C15000 Copper Zirconium, the highest electrical and thermal conductivity. 

Class 2:

C18150 Copper Chromium Zirconium, the go-to for seam weld wheels & electrodes for galvanized steel.
C18200 Copper Chromium, the go-to for electrodes.

Class 3:

C18000 Copper Nickel Silicon Chromium, the go-to for resistance welding consumables where some conductivity is sacrificed for high strength.
C17510 Copper Nickel Beryllium, the go-to for electrodes and welding dies, where some conductivity is sacrificed for high strength.

Class 4:

C17200 Copper Beryllium, where maximum strength is required for mechanical components. Note: 2024 due to the war with Russia/Ukraine has disrupted the supply of beryllium and therefor has driven the price up and created a shortage.

According to Tom Chandler, Senior Metallurgist at Cadi Company,
“Copper alloys have evolved over the past 40 years to being the “go-to” alloys for resistance welding products.”

He remembers the introduction of CuCrZr (C18150) in the US market in the mid-1980s to improve the spot-welding process for galvanized steel in the auto industry. 

*Resistance Welding Manufacturers Alliance, part of the American Welding Society