Specifying the wrong grade of copper for a high-temperature application is an expensive mistake. While C11000 (Electrolytic Tough Pitch - ETP) and C10100 Oxygen-Free Electronic (OFE) copper look identical to the naked eye and offer similar electrical conductivity, their performance under high heat is drastically different.
If your manufacturing process involves brazing, welding, or glass-to-metal sealing in a reducing atmosphere, choosing C11000 will likely result in catastrophic failure. The culprit? Hydrogen Embrittlement.
The Trap of C11000 (ETP) Copper
C11000 is the most common copper used in general electrical wiring. It boasts a purity of 99.90% and good conductivity. However, it contains a microscopic amount of oxygen-typically between 0.02% and 0.04% (200-400 ppm)-intentionally left in the metal during casting to improve flowability.
For standard applications operating at room temperature, this oxygen is harmless. But expose C11000 to temperatures above 400°C (752°F) in an environment containing hydrogen gas (such as during vacuum brazing or welding), and a destructive chemical reaction occurs.
The hydrogen atoms penetrate the metal lattice and react with the trapped oxygen to form water vapor. This trapped steam expands rapidly, creating intense internal pressure. The result is microscopic blistering and severe cracking along the grain boundaries. The copper becomes completely brittle, loses structural integrity, and fails the vacuum seal.
100% Immunity with C10100 (OFE) Copper
At GNEE METAL, we strictly recommend C10100 for any application requiring high-temperature processing or absolute vacuum integrity.
Unlike ETP copper, C10100 is specifically smelted and cast under stringent vacuum conditions to eliminate oxygen and other volatile elements. With a guaranteed purity of 99.99% and oxygen levels strictly controlled below 0.0005% (5 ppm), there is simply no oxygen left in the matrix to react with hydrogen.
Because it is completely oxygen-free, C10100 achieves 100% immunity to hydrogen embrittlement.
Solve Your Material Selection Problem
When Must You Specify C10100?
If your components will be subjected to the following conditions, the cost savings of C11000 are never worth the risk of system failure:
Ultra-High Vacuum (UHV) Systems: Outgassing is unacceptable in electron tubes, particle accelerators, and klystrons. We supply leak-tight C10100 seamless copper tubes specifically engineered to hold strict vacuums without microscopic porosity.
Cryogenic Cooling & MRI: At sub-zero temperatures, ordinary copper loses ductility. C10100 maintains its mechanical strength and exceptional thermal conductivity, making it ideal for cryogenic applications.
Precision CNC Machining & Brazing: If you are manufacturing custom switchgear contacts or RF coaxial connectors that require silver brazing, starting with high-purity machined C10100 copper rods ensures your final assemblies will not crack under thermal stress.
| Technical Feature | C10100 (OFE Copper) | C11000 (ETP Copper) | The Advantage of C10100 |
| Copper Purity (Cu) | 99.99% Minimum | 99.90% Minimum | Fewer impurities for cleaner signal/power. |
| Oxygen Content | < 0.0005% (5 ppm) | 0.02% - 0.04% (200-400 ppm) | Prevents internal oxidation and failure. |
| Hydrogen Embrittlement | 100% Immune | High Risk (Susceptible) | Safe for high-temp welding and brazing. |
| UHV Performance | Zero Outgassing | High Outgassing (Unsuitable) | Essential for Ultra-High Vacuum (UHV) seals. |
| Electrical Conductivity | 101% IACS Minimum | 100% - 101% IACS | Higher efficiency, less heat in high-load use. |
| Thermal Conductivity | 391 W/m·K | 388 W/m·K | Superior cooling in cryogenic environments. |
| Manufacturing Method | Cast in a Vacuum Atmosphere | Electrolytic Refining | Higher density and refined grain structure. |
| Primary Industry | Semiconductors, Medical, Aerospace | General Power, Architecture, Motors | Engineered for failure-critical projects. |
Don't Risk Your Supply Chain
A major issue in global sourcing is receiving "oxygen-free" copper that is actually standard ETP copper. Visual inspection cannot tell the difference.
We do not take risks with your raw materials. As an ISO 9001:2015 certified supplier, GNEE METAL verifies the chemical composition of every C10100 batch using advanced spectrometer analysis. All materials are backed by rigorous SGS testing and come with batch-specific Material Test Reports (MTR) confirming max 5ppm oxygen.
You need copper that performs exactly as specified, every single time. We deliver it.
Talk to Our Experts & Get a C10100 Quote
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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