MetalsWhat is C18200 copper and what is it used for? Beryllium-free chromium copper
C18200 copper is chromium copper, beryllium-free. In this guide we explain what C18200 copper is, its composition, its properties, what it is used for and the sizes we stock.
What is C18200 copper?
C18200 copper (copper-chromium, CuCr1) is a precipitation-hardening alloy that combines high electrical and thermal conductivity with good mechanical strength and hardness. It is the benchmark beryllium-free RWMA Class 2 chromium copper, widely used in resistance welding electrodes and wheels, electrode holders and high-conductivity components.
Chemical composition of C18200 copper
This is the typical composition of C18200 copper (UNS C18200 / RWMA Class 2 / EN CW105C / DIN 2.1291 / JIS C1820 standard):
| Element | Contents | What for? |
|---|---|---|
| Chromium (Cr) | 0.60 – 1.20 % | Chromium: increases strength and hardness through precipitation |
| Iron (Fe) | 0.10 % max. | Iron, kept limited |
| Silicon (Si) | 0.10 % max. | Silicon: forms hardening compounds |
| Lead (Pb) | 0.05 % max. | Lead, kept limited |
| Copper (Cu) | Balance | Base metal |
C18200 properties and treatment
C18200 (copper-chromium) is precipitation hardenable and combines high conductivity with good mechanical strength and hardness. It is the benchmark chromium copper, an RWMA Class 2, beryllium-free material widely used in resistance welding electrodes, wheels and dies, electrode holders and high-conduction components.
What is it for? Applications of C18200
C18200 copper is mainly used in:
- Resistance welding electrodes
- Welding wheels and tips
- Welding dies
- Electrode holders and arms
- Back-up bars
- Contacts and switching
- Conductor bars (bus bars)
- Mold inserts and heat sinks
- Electrical switch components
Forms and sizes we carry
At NAT MAC we stock C18200 copper in these forms and sizes:
| Package size | Sizes |
|---|---|
| Round bars | 1/4" – 3" (6.35 – 76.2 mm) |
| Plates | 1/8" – 3" (3.18 – 76.2 mm) |
If you need a particular size, tell us which one and we will gladly source it for you.
C18200 equivalents and standards
C18200 copper is also identified by these standards: UNS C18200 / RWMA Class 2 / EN CW105C / DIN 2.1291 / JIS C1820. You can see how to read them in our article on metal standards.
In summary
- C18200 is chromium copper, beryllium-free (RWMA Class 2)
- Precipitation hardenable; high conductivity with good strength and hardness
- Ideal for resistance welding electrodes, wheels and dies
- We carry it in round bars, plates, cut to size
Why buy your C18200 copper at NAT MAC?
We have more than 54 years of experience as an industrial supplier and ISO 9001 certified quality. We carry copper and its alloys, and we help you choose the right grade for your application.
- Quality C18200 copper, fully backed and traceable
- Material cut to the size you need
- Advice on choosing the right copper for your conductivity and strength needs
- Electrolytic copper and high-performance alloys
- On-time deliveries and competitive prices
Tell us what you'll make and what you need (conductivity, strength or weldability), and we'll recommend the right copper and form. Request your free quote.
Sources: data sheet from our NAT MAC catalog (composition, sizes and applications) and public references from the copper industry. Values are for reference and may vary by standard, temper and heat.
