C18000 Beryllium Free Square Bar (Class 3)

These copper bars have similar performance properties to beryllium copper, but do not require special machining techniques. They’re often used for high-stress applications such as studs, welding electrodes, mold cavities, and electrical components. Even after collisions and frequent use, they maintain their shape. They conduct electricity, but not as well as purer copper, such as 101 copper. Using them in extreme temperatures won’t change their mechanical properties, but you can process them with heat treatment if you wish to alter their properties. They’re RMWA Class 3, which is a class that’s commonly used to seam and spot weld stainless steel and other electrically-resistant materials. When used outdoors, these bars won’t rust.


C18000 is utilized when a combination of very good mechanical strength along with moderate electrical and thermal electrical conductivity are required. C18000 is a viable substitute for C17500 and C17510 for many applications. C1800 is a heat treatable copper alloy. Beryllium Free (C180000) meets the mechanical requirements of RWMA Class 3 Copper.

Typical Uses

Resistance welding tips, resistance welding wheels and fixtures, stud welding collets and tips, sprue bushings, cavities for injection molds, hot runner systems for injection molds, welding dies for wire and flash, blow pins, pinch offs, core and ejector pins for injection molds, plunger tips for metal die casting machines, heat sink inserts in steel plastic molds.

Other Designations

C18000, CA 180, CDA 180, CuCr, UNS C18000, Beryllium Free Copper, Copper Alloy UNS C18000, RWMA Class III Copper, RWMA Alloy C18000, NiSiCr, ThermoMet