C18000 Class 3 Beryllium-Free Copper – RWMA Class 3 Alloy
C18000 Copper-Nickel-Silicon-Chromium from NSRW is an RWMA Class 3 copper alloy that combines excellent mechanical strength with moderate electrical and thermal conductivity. Unlike traditional Class 3 alloys, C18000 is beryllium-free, making it a safer alternative to C17510 while still meeting the same strength and conductivity requirements.
Because it’s a hard heat-treatable copper, C18000 can be strengthened through heat treatment and precipitation hardening to withstand high temperatures and repeated heavy-duty service. This feature makes it ideal for resistance welding wheels, projection welding electrodes, spot and seam welding tools, stud welding collets, and components in metal die casting machines and hot runner systems.
What is C18000 Copper-Nickel-Silicon-Chromium?
C18000 combines copper, nickel, silicon, and chromium to create an alloy with balanced mechanical and physical properties. It falls into the RWMA Class 3 category, the standard for materials used in resistance welding and heavy-duty current-carrying parts.
C18000 offers the performance of other Class 3 alloys without relying on beryllium. That means manufacturers get the same hardness, wear resistance, and service life as they do from C17510, but with safer handling and easier compliance with workplace safety rules.
For companies under stricter health standards or looking to phase out beryllium, C18000 is a dependable, practical alternative.
C18000 Copper Properties & Specifications
Minimum Physical Properties
Diameter – Round Stock (Cold Worked)
| Size Range in MM | Size Range in MM | Hardness Rockwell | Conductivity % I.A.C.S. | Yield Strength KSI (typical) | Ultimate Tensile Strength (typical) | Elongation % *(typical) |
| Up to 1″ | Up to 22 | 90 HRB | 45% | 90 | 95 | 9% |
| Over 1″ to 2″ | Over 25 to 51 | 90 HRB | 45% | 90 | 92 | 9% |
| Over 2″ to 3″ | Over 51 to 76 | 90 HRB | 45% | 90 | 88 | 9% |
Thickness – Square, Rectangle, and Hexagonal Bar Stock (Cold Worked)
| Size Range in MM | Size Range in MM | Hardness Rockwell | Conductivity % I.A.C.S. | Yield Strength KSI (typical) | Ultimate Tensile Strength (typical) | Elongation % *(typical) |
| Up to 1″ | Up to 25 | 90 HRB | 45% | 90 | 95 | 9% |
| Over 1″ | Over 25 | 90 HRB | 45% | 90 | 90 | 9% |
Thickness – Forgings
| Size Range in MM | Size Range in MM | Hardness Rockwell | Conductivity % I.A.C.S. | Yield Strength KSI (typical) | Ultimate Tensile Strength (typical) | Elongation % *(typical) |
| Up to 1″ | Up to 25 | 90 HRB | 45% | 50 | 94 | 9% |
| Over 1″ to 2″ | Over 25 to 51 | 90 HRB | 45% | 50 | 90 | 9% |
| Over 2″ | Over 51 | 90 HRB | 45% | 50 | 88 | 9% |
Chemical Composition
| Cu | Fe | Ni | Cr | Si |
| Rem. | .15 max | 1.8 – 30 | .1 – .8 | .4 – .8 |
Benefits of Beryllium-Free Copper
- Eliminates health and safety hazards associated with beryllium-containing alloys
- Offers improved machinability and handling in production settings
- Maintains durability and longevity in welding and tooling operations
- Ensures reliable performance in sectors governed by strict safety regulations
Fabrication & Machining Characteristics
C18000 beryllium-free copper can be fabricated into custom tooling, bushings, and electrodes with the following characteristics:
- Hot Working: Good
- Cold Working: Good
- Machinability: Moderate
- Welding Compatibility: Suitable for brazing, soldering, and gas shielded arc welding
Applications of C18000 Class 3 Copper
Its balance of hardness and moderate conductivity makes C18000 useful for:
- Projection welding dies
- Flash and butt welding dies
- Resistance welding electrodes
- Heavy-duty electrode holders
- Current-carrying shafts and bushings
- Aerospace and automotive tooling
- Electrical connectors and conductive parts
Why Choose C18000 Over C17510?
C18000 is often selected as a replacement for C17510 Class 3 Beryllium Copper because it offers:
- Safer handling: Eliminates strict beryllium exposure controls
- Easier machining: Fewer precautions required during fabrication and finishing
- Regulatory compliance: Since it’s beryllium-free, C18000 helps companies stay aligned with safety standards without the burden of ongoing compliance requirements
- Lower long-term costs: Reduces expenses for protective equipment, training, and compliance programs.
- Same performance class: Even without beryllium, C18000 maintains the high hardness, strength, wear resistance, and moderate electrical conductivity as Class 3 alloys
See our Electrodes & Tooling Solutions for more applications.
Supply Options from NSRW
We offer C18000 in a variety of forms, including:
- Bars, rods, and plates
- Custom-machined parts and electrodes
- Heat-treated or mill-hardened options
- Certifications provided upon request
With nationwide distribution and technical expertise, NSRW can supply both raw material and custom-fabricated C18000 components.
Request a Quote for C18000 Beryllium-Free Copper
Are you looking for a high-copper alloy with high hardness, outstanding mechanical strength, and safe handling at high temperatures? At NSRW, we supply C18000 in multiple forms and can machine it to your specifications. Contact us to request pricing, availability, or technical support for your project.
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