Which Copper Grade Should You Choose?
For 95% of electrical applications – including switchgear, panel boards, busway systems, and grounding – C11000 is the best choice. It delivers ≥101% IACS conductivity at a fraction of the cost of oxygen-free copper.
Only choose C10100 (oxygen-free) if your application involves: vacuum environments (<10⁻⁵ torr), hydrogen brazing above 370°C, or cryogenic temperatures below -150°C. Otherwise, you are paying 30-50% more for no performance gain.
C1100 and T2 are equivalent to C11000 – just different naming systems. A C1100 busbar from Japan or a T2 busbar from China is the same material as an ASTM C11000 busbar.
Browse our C11000 copper busbar product page for detailed specifications and current pricing.
C11000 vs. C10100 vs. C1100
| Grade | Standard | Full Name | Purity | Oxygen Content |
|---|---|---|---|---|
| C11000 | UNS / ASTM | Electrolytic Tough Pitch (ETP) | ≥99.9% | 0.02-0.04% |
| C10100 | UNS / ASTM | Oxygen-Free Electronic (OFE) | ≥99.99% | ≤0.0005% |
| C1100 | JIS (Japan) | Electrolytic copper | ≥99.9% | 0.02-0.04% |
| T2 | GB (China) | Pure copper | ≥99.9% | 0.02-0.04% |
| CW004A | EN (Europe) | Cu-ETP | ≥99.9% | 0.02-0.04% |
C11000, C1100, T2, and CW004A are equivalent grades. They are the same material with the same properties, just named according to different regional standards. C10100 is a different, higher-purity grade with specific niche applications.
C11000 vs. C10100
| Property | C11000 (ETP) | C10100 (OFE) |
|---|---|---|
| Purity | 99.9% | 99.99% |
| Oxygen content | 0.02-0.04% (200-400 ppm) | ≤0.0005% (≤5 ppm) |
| Conductivity (% IACS) | ≥100% (typically 101%) | ≥100% (typically 101-102%) |
| Thermal conductivity | 401 W/m·K | 401 W/m·K |
| Tensile strength (half-hard) | 200-250 MPa | 200-250 MPa |
| Relative price | Baseline (1×) | 1.3× to 1.5× |
| Hydrogen embrittlement risk | Yes (in H₂ at >370°C) | No |
| Vacuum compatibility | No (oxygen outgasses) | Yes |
| Cryogenic performance | Good | Excellent (better ductility) |
For conductivity, thermal performance, and mechanical strength, both grades are identical. The price difference buys you oxygen removal, which only matters in specialized applications.
C11000 vs. C1100 vs. T2 – Are They the Same?
Yes – these three are the same material.
| Equivalent | ||
|---|---|---|
| C11000 | ASTM/UNS standard name | – |
| C1100 | JIS (Japanese) name | C11000 |
| T2 | GB (Chinese) name | C11000 |
| CW004A | EN (European) name | C11000 |
| Cu-ETP | ISO name | C11000 |
When Do You Need C10100 (Oxygen-Free Copper)?
1. Vacuum Environments (<10⁻⁵ torr)
In high vacuum systems, the 0.02-0.04% oxygen in C11000 can outgas, releasing water vapor and contaminating the vacuum chamber. C10100, with its ≤5 ppm oxygen content, does not have this problem.
2. Hydrogen Brazing Above 370°C
When C11000 is heated above 370°C in a hydrogen atmosphere, hydrogen diffuses into the copper and reacts with oxygen to form steam (H₂O) . The steam pressure creates internal cracks – a phenomenon called "hydrogen embrittlement" or "hydrogen disease." C10100 has no oxygen, so this reaction cannot occur.
3. Cryogenic Temperatures Below -150°C
At extremely low temperatures (liquid hydrogen, liquid helium applications), C10100 offers better ductility and impact strength than C11000. Most cryogenic engineers prefer oxygen-free copper for this reason.
If your project does NOT involve these three conditions, C11000 is sufficient – and saves you 30-50%.
How Much Can You Save by Choosing C11000?
C11000 is 30-50% cheaper than C10100 for identical conductivity.
| Order Quantity | C10100 (OFE) Estimated Price | C11000 (ETP) Estimated Price | Your Savings |
|---|---|---|---|
| 500 kg | $7,000 – $8,500 | $4,500 – $5,500 | $2,500 – $3,000 |
| 1,000 kg | $12,000 – $15,000 | $8,000 – $10,000 | $4,000 – $5,000 |
| 5,000 kg | $55,000 – $70,000 | $35,000 – $45,000 | $20,000 – $25,000 |
For a typical switchgear project using 1,000 kg of busbar, choosing C11000 over C10100 saves $4,000-5,000 with absolutely no difference in electrical performance.
How We Test and Certify Our C11000 Copper Busbar
| Test | Equipment | Standard | Frequency |
|---|---|---|---|
| Chemical composition | Optical emission spectrometer | Cu ≥99.9%, O 0.02-0.04% | Every batch |
| Electrical conductivity | Eddy current sigmascope | ≥101% IACS | Every batch |
| Hardness | Rockwell hardness tester | HV 60-85 (half-hard) | Every batch |
| Tensile strength | Universal testing machine | ≥200 MPa (half-hard) | Every batch |
| Dimensional accuracy | Hexagon CMM / precision calipers | ±0.1mm (width/thickness) | 100% of pieces |
| Surface finish | Visual inspection + profilometer | No scratches, pits, or burrs | 100% of pieces |
| Plating thickness (if applicable) | XRF analyzer | Tin 3-8μ / Silver 5-15μ | Every batch |
| Salt spray corrosion | ASTM B117 chamber | ≥96 hours no red rust (plated) | Weekly |
We provide a Material Test Certificate (MTC) with every shipment, traceable to the production batch number. You receive documented proof that your copper meets or exceeds all specified requirements.
Our Factory
| Equipment | Brand/Capability |
|---|---|
| Induction melting furnace | 15,000 kg capacity |
| Continuous casting machine | Up to 200mm width |
| Extrusion press | 550 ton |
| Cold rolling mill | Precision thickness control |
| CNC shearing machine | Up to 30mm thickness, 250mm width |
| AMADA CNC punching press | Hole tolerance ±0.1mm |
| ACCURL CNC press brake | Bending up to 3000mm length, ±1° tolerance |
| Automatic in-house plating line | Tin / silver / nickel, up to 4000mm length |
Custom Capabilities:
- Thickness: 3mm to 30mm
- Width: 10mm to 250mm
- Length: Up to 6000mm (single piece)
- Shapes: Flat, round edge, L-bend, Z-bend, U-bend, custom angles
- Holes: Round (4-20mm), slotted (6×12mm to 10×25mm), counterbored
- Surface finishes: Bare, tin-plated, silver-plated, nickel-plated, heat shrink tubing, epoxy coating
Lead Times:
- Sample orders (any size): 5-7 business days
- Standard sizes (bare): 10-15 business days
- With plating: 15-20 business days
- Custom fabrication: 15-20 business days
How We Package
| Layer | Material | Purpose |
|---|---|---|
| Inner wrap | VCI (Vapor Corrosion Inhibitor) film | Prevents oxidation – VCI molecules settle on all copper surfaces, blocking moisture and oxygen |
| Interleaving | Kraft paper + foam sheet | Prevents scratching between stacked busbar layers |
| Bundling | Steel straps (3-5 straps per bundle) | Secures multiple busbars into stable bundles |
| Pallet | Heat-treated plywood (IPPC certified) | No fumigation required for customs clearance |
| Corner protection | Plastic or cardboard corner guards | Prevents strap damage to edges |
| Outer wrap | Stretch film (multiple layers) | Seals out moisture and dust |
| Optional | Custom foam cradles (for bent shapes) | Prevents deformation during transit |
For ocean freight: This packaging system protects copper busbar for 60+ days in marine environments without corrosion.
For air freight / courier (DHL/FedEx/UPS): We use heavy-duty cardboard boxes with internal foam padding, suitable for shipments under 500kg.
FAQ
Q1: Is C11000 the same as C1100 copper?
Answer: Yes – they are the same material under different naming systems. C11000 is the ASTM/UNS standard name (used in North America). C1100 is the JIS standard name (used in Japan). Both have ≥99.9% purity and ≥100% IACS conductivity. A C1100 busbar is fully interchangeable with a C11000 busbar.
Q2: Is C11000 copper oxygen-free?
Answer: No – C11000 contains 0.02-0.04% oxygen (200-400 ppm). The oxygen is intentionally added during refining to improve conductivity and workability. For true oxygen-free copper, you need C10100 (≤5 ppm oxygen) or C10200 (≤10 ppm oxygen). For most electrical applications, the oxygen in C11000 does not cause any problems.
Q3: What is the difference between ETP copper and OFHC copper?
Answer: ETP (Electrolytic Tough Pitch) copper contains 0.02-0.04% oxygen; OFHC (Oxygen-Free High Conductivity) copper contains ≤0.001% oxygen. C11000 is ETP copper. C10100 and C10200 are OFHC grades. Conductivity is identical (≥100% IACS). OFHC costs 30-50% more and is only required for vacuum, hydrogen brazing, or cryogenic applications.
Q4: Can I weld C11000 copper busbar?
Answer: Yes, but you need proper technique. C11000 can be welded using TIG (GTAW) or MIG (GMAW) processes with deoxidized filler metal (e.g., ERCu). The oxygen content can cause porosity if welding parameters are incorrect. For critical welded joints, consider using C10100 or C10200 instead, as they weld more cleanly. For most busbar connections, bolted joints are preferred over welding.
Q5: Is C11000 suitable for grounding and bonding?
Answer: Yes – it is the most common grounding material worldwide. C11000's combination of high conductivity (≥101% IACS), corrosion resistance, and mechanical strength makes it ideal for grounding grids, equipment bonding conductors, and lightning protection systems. For outdoor or coastal grounding, specify tin-plated C11000 copper busbar for added corrosion protection.
Q6: Does C11000 copper corrode in coastal environments?
Answer: Bare C11000 will develop a surface patina (green or dark brown) but this does not significantly affect conductivity. In severe coastal or industrial environments with high salt or sulfur, tin-plated C11000 is recommended. The tin layer provides a sacrificial barrier that protects the copper for 20-30 years. Our salt spray testing shows tin-plated C11000 withstands ≥96 hours without red rust.
Q7: What is the maximum operating temperature for C11000 busbar?
Answer: For continuous operation, 105°C is the standard maximum for insulated busbars; up to 250°C for bare busbars with proper clearances. The material itself does not degrade until above 500°C. The limit comes from:
- Insulation rating (if sleeved or coated)
- Clearance to other components
- Contact resistance at joints (which increases with temperature)
For high-temperature applications (>150°C), use nickel-plated C11000 to prevent surface oxidation.
Q8: Can I bend C11000 copper busbar without cracking?
Answer: Yes – C11000 has excellent ductility when properly annealed or ordered in half-hard temper. Minimum bend radius guidelines:
- Annealed (soft) temper: 0.5× thickness
- Half-hard (H02) temper: 1.5× thickness
- Hard (H04) temper: 3× thickness (not recommended for bending)
For tight bends, we recommend annealed C11000 busbar or having us perform the bending (we stress-relieve after bending). Never bend hard-temper busbar – it will crack.
Get Free Sample & Evaluation
