In heavy-duty electrical engineering, the choice between C10100 (OFE) and C18200 (Chromium Copper) is a struggle between maximizing electrical throughput and resisting thermal deformation. If your component is a stationary conductor, C10100 is the undisputed king. However, if your part must endure the mechanical stress of resistance welding or high-speed switching at elevated temperatures, C18200 is often the designated alloy.
For a procurement manager, the risk lies in using C18200 where C10100 Oxygen-Free Electronic copper is required, resulting in a 20% "conductivity tax" that manifests as localized hotspots.
Softening Temperature: Why C18200 Resists Heat Better Than C10100
The primary reason engineers specify C18200 is its resistance to softening. C18200 is a precipitation-hardened alloy containing approximately 0.6% to 1.2% Chromium. This addition creates a material that maintains its hardness at temperatures where pure copper becomes dangerously soft.
C10100 (OFE): Begins to anneal (soften) at approximately 200 Celsius.
C18200 (CrCu): Retains its mechanical properties up to 450 - 500 Celsius.
If your application is an internal busbar in a temperature-controlled cabinet, the 101% IACS conductivity of C10100 Round, Square & Flat Bar is the superior choice. But for a spot-welding electrode, the high softening temperature of C18200 prevents the tip from "mushrooming" under pressure.
Technical Spec Comparison: C10100 vs. C18200
| Metric | C10100 (OFE Grade 1) | C18200 (Chromium Copper) | Engineering Impact |
| Purity | 99.99% Min | ~98.8% (Alloyed) | C10100 for UHV/Semicon |
| Conductivity | 101% IACS | 80% - 85% IACS | C10100 is 20% more efficient |
| Hardness (HRB) | 40 - 50 | 75 - 82 | C18200 resists wear/impact |
| Thermal Cond. | 391 W/m-K | ~320 W/m-K | C10100 dissipates heat faster |
| Oxygen Content | < 5 ppm | Uncontrolled | C10100 is safer for brazing |
Consult GNEE Engineers: Should You Use C10100 or C18200?
The Efficiency Trade-off: Calculating the I-squared R Loss
The Chromium in C18200 acts as an impurity in the copper lattice, scattering electrons and dropping the conductivity to around 80% IACS. For large-scale industrial infrastructure, this 20% drop is significant.
When you use C18200 for a power connector that doesn't face mechanical wear, you are essentially wasting 20% of your electrical efficiency as heat (I-squared R losses). Our 99.99% pure C10100 ensures that your power distribution system operates at the highest possible efficiency. If you are manufacturing Custom CNC Machined Parts, choosing C10100 can reduce the overall cooling requirements of your enclosure.
When to Specify C10100 over C18200
Vacuum Stability: C18200 is unsuitable for ultra-high vacuum (UHV) because the alloying elements can outgas. Always use C10100 for vacuum electronics.
High-Current Busbars: Use C10100. The energy savings over the lifecycle of a 101% IACS busbar far outweigh the initial material cost.
Resistance Welding: Use C18200. C10100 will deform too quickly under the heat and pressure of the welding cycle.
Brazed Assemblies: If your part requires high-temperature brazing, refer to our guide on C10100 brazing rules. Pure C10100's < 5 ppm oxygen ensures a crack-free joint that alloyed coppers cannot guarantee.
Procurement is about more than just buying the strongest or the cheapest copper; it is about matching the metallurgical profile to the operational stress. C10100 Oxygen-Free Electronic copper is the premium choice for electrical and thermal efficiency in non-abrasive environments. GNEE METAL provides certified Grade 1 C10100, ensuring your high-performance systems operate with the maximum possible safety margin and zero contamination.
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GNEE METAL Product Range
| Product Type | Shapes Available | Common Grades | Diameter/Thickness Range | Length/Width Range | Applications |
|---|---|---|---|---|---|
| Copper Tubes | Round, Square, Rectangular, Coiled | C10100, C10200, C11000, C12200, C12000 | OD: 0.5mm - 300mm Wall: 0.1mm - 20mm | Up to 6000mm or custom | HVAC, Plumbing, Heat Exchangers, Refrigeration, Hydraulic Lines |
| Copper Plates & Sheets | Flat Sheets, Perforated, Embossed, Tread Plate | C10100, C11000, C12200, C23000, C26000 | Thickness: 0.1mm - 200mm | Width: Up to 2500mm Length: Up to 6000mm | Electrical Busbars, Roofing, Cladding, Gaskets, Transformers |
| Copper Bars & Rods | Round Bar, Square Bar, Hexagonal Bar, Flat Bar | C10100, C11000, C14500, C17200, C18200 | Diameter: 1mm - 300mm | Length: 1000mm - 4000mm | Machined Components, Electrical Contacts, Busbars, Fasteners |
| Copper Wires | Round Wire, Flat Wire, Square Wire, Stranded, Braided | C11000, C11600, C17200, C17510 | Diameter: 0.05mm - 12mm | Coil weights: 1kg - 500kg | Electrical Wiring, Cables, Springs, Mesh, Welding Wire |
| Copper Strips & Coils | Thin Strip, Foil, Slit Coil, Profile Strip | C11000, C12200, C19400, C26000, C26800 | Thickness: 0.03mm - 5mm | Width: 2mm - 1000mm Coil ID: 300mm - 600mm | Transformers, Radiators, Shielding, Terminals, Connectors |
About Our Factory
We operate a full range of production lines including extrusion presses, cold drawing benches, high-speed rolling mills, slitting lines, and precision CNC machining centers, enabling us to produce copper tubes, plates, bars, wires, and strips entirely in-house. For quality assurance, we maintain a dedicated inspection laboratory equipped with spectral analyzers, universal testing machines, hardness testers, surface roughness testers, and optical measuring instruments. Every batch is tested for chemical composition, mechanical properties, and dimensional accuracy before shipment. Our production capacity reaches 500+ tons per month, and we hold ISO 9001:2015 certification with full traceability from raw material to finished product. Whether you need standard mill stock or custom-processed components, we deliver precision copper products with short lead times and complete material certification.
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