C10100 oxygen-free copper represents the pinnacle of copper purity in industrial applications, offering exceptional electrical and thermal conductivity that surpasses standard copper grades. This material is specifically engineered for high-performance electrical components where minimal oxygen content—typically below 5 ppm—ensures superior conductivity and resistance to hydrogen embrittlement. As a senior materials engineer at Dongguan Stirling Metal Products Co., Ltd., I have extensive experience machining this demanding alloy, and in this article, I will detail its chemical composition, mechanical properties, CNC machining parameters, and real-world applications with precise technical data.
1. C10100 Basic Information
C10100, also known as oxygen-free electronic copper (OFE), is a high-purity copper alloy with a copper content of 99.99% minimum. It is produced through a specialized refining process that removes oxygen and other impurities, resulting in a material with exceptional electrical conductivity of 101% IACS (International Annealed Copper Standard) and thermal conductivity of 391 W/m·K at 20°C. This grade is widely used in electrical, electronic, and telecommunications industries for applications requiring minimal signal loss and high heat dissipation. The material’s fine grain structure and absence of oxygen make it ideal for vacuum environments and high-frequency applications.
2. Chemical Composition
The chemical composition of C10100 is strictly controlled to ensure maximum purity and performance. The following table provides the standard composition ranges per ASTM B152/B152M and ASTM F68 specifications:
| Element | Content (%) | Specification |
|---|---|---|
| Copper (Cu) + Silver (Ag) | 99.99 min | ASTM B152 |
| Oxygen (O) | 0.0005 max | ASTM F68 |
| Phosphorus (P) | 0.0003 max | ASTM B152 |
| Iron (Fe) | 0.0010 max | ASTM B152 |
| Lead (Pb) | 0.0005 max | ASTM B152 |
| Bismuth (Bi) | 0.0005 max | ASTM B152 |
| Antimony (Sb) | 0.0004 max | ASTM B152 |
| Arsenic (As) | 0.0005 max | ASTM B152 |
| Tin (Sn) | 0.0002 max | ASTM B152 |
| Nickel (Ni) | 0.0010 max | ASTM B152 |
| Zinc (Zn) | 0.0001 max | ASTM B152 |
| Sulfur (S) | 0.0015 max | ASTM B152 |
| Hydrogen (H) | 0.0005 max | ASTM F68 |
Note: The total impurity content must not exceed 0.01% to maintain the 99.99% purity requirement. The oxygen content is critically low (<5 ppm) to prevent embrittlement during welding or brazing operations. Additionally, the silver content is often included in the copper minimum to enhance creep resistance at elevated temperatures, a critical factor for high-current applications.
3. Mechanical & Physical Properties
C10100 exhibits a unique combination of high ductility, moderate strength, and excellent conductivity. The following tables summarize its key mechanical and physical properties based on ASTM standards and typical test data:
Mechanical Properties (Annealed Condition)
| Property | Value | Unit | Test Standard |
|---|---|---|---|
| Tensile Strength | 220-260 | MPa | ASTM E8 |
| Yield Strength (0.2% offset) | 70-100 | MPa | ASTM E8 |
| Elongation (in 50 mm) | 45-55 | % | ASTM E8 |
| Hardness (Rockwell F) | 45-55 | HRF | ASTM E18 |
| Hardness (Vickers) | 85-105 | HV | ASTM E92 |
| Modulus of Elasticity | 115-130 | GPa | ASTM E111 |
| Poisson’s Ratio | 0.34 | – | ASTM E132 |
Physical Properties
| Property | Value | Unit | Condition |
|---|---|---|---|
| Density | 8.94 | g/cm³ | At 20°C |
| Electrical Conductivity | 101 | %IACS | At 20°C (annealed) |
| Electrical Resistivity | 1.7241 × 10⁻⁸ | Ω·m | At 20°C |
| Thermal Conductivity | 391 | W/m·K | At 20°C |
| Specific Heat Capacity | 385 | J/kg·K | At 20°C |
| Thermal Expansion Coefficient | 16.5 × 10⁻⁶ | 1/K | 20-100°C |
| Melting Point | 1083 | °C | Pure copper |
| Magnetic Permeability | <1.01 | µ | Non-magnetic |
These properties make C10100 ideal for applications requiring high electrical efficiency, such as power transmission cables, RF connectors, and superconducting magnet windings. The low oxygen content ensures resistance to hydrogen embrittlement during welding, a critical advantage over standard electrolytic tough pitch copper (C11000). Furthermore, the thermal conductivity of 391 W/m·K is approximately 10% higher than C11000, enabling superior heat dissipation in high-power electronics.
4. CNC Machining Characteristics
Machining C10100 requires careful parameter selection due to its high ductility and thermal conductivity. The material tends to form long, stringy chips that can cause tool wear and surface finish issues if not managed properly. Based on our extensive experience at Dongguan Stirling Metal Products Co., Ltd., we recommend the following CNC machining parameters for optimal results:
Recommended CNC Machining Parameters
| Operation | Cutting Speed (m/min) | Feed Rate (mm/rev) | Depth of Cut (mm) | Tool Material | Coolant |
|---|---|---|---|---|---|
| Turning (Roughing) | 150-250 | 0.15-0.30 | 1.0-3.0 | Carbide (K10-K20) | Water-soluble oil (5-10% emulsion) |
| Turning (Finishing) | 200-350 | 0.05-0.15 | 0.2-0.5 | Carbide (K10) or PCD | Water-soluble oil (5-10% emulsion) |
| Milling (Roughing) | 120-200 | 0.10-0.25 (per tooth) | 1.0-2.5 | Carbide (K20-K30) | Water-soluble oil (5-10% emulsion) |
| Milling (Finishing) | 180-300 | 0.05-0.12 (per tooth) | 0.2-0.5 | Carbide (K10) or PCD | Water-soluble oil (5-10% emulsion) |
| Drilling | 80-150 | 0.08-0.20 | N/A | HSS-Co or Carbide | Water-soluble oil (5-10% emulsion) |
| Threading | 30-60 | 0.05-0.10 | N/A | Carbide (K10) | Water-soluble oil (5-10% emulsion) |
Key machining considerations for C10100 include:
- Chip Control: Use chip breakers or peck drilling cycles to prevent long, stringy chips from wrapping around the tool or workpiece. Chip breakers with a 0.2-0.5 mm step are recommended for turning operations.
- Tool Wear: Due to the material’s low hardness, tool wear is generally low, but built-up edge (BUE) can occur at low cutting speeds. Maintain cutting speeds above 150 m/min to minimize BUE. For PCD tools, expect tool life exceeding 5000 parts in production runs.
- Surface Finish: Achievable surface roughness (Ra) of 0.4-0.8 µm with finishing passes. Use PCD tools for mirror finishes (Ra < 0.2 µm). In our facility, we consistently achieve Ra 0.1 µm on critical sealing surfaces.
- Coolant: Flood coolant is essential to dissipate heat and lubricate the cutting zone. Avoid oil-based coolants that may leave residues affecting electrical conductivity. Water-soluble emulsions at 5-10% concentration provide optimal cooling and chip evacuation.
- Work Hardening: C10100 does not work-harden significantly, but excessive deformation can lead to microstructural changes. Use sharp tools and consistent feed rates. For deep cuts exceeding 3 mm, consider stress-relief annealing at 250°C for 30 minutes.
- Thermal Management: Due to high thermal conductivity, heat is rapidly conducted away from the cutting zone. This can lead to thermal expansion issues in thin-walled parts. Pre-heating the workpiece to 50-80°C can improve dimensional stability.
5. Typical Applications
C10100’s unique combination of high electrical conductivity, thermal conductivity, and corrosion resistance makes it indispensable in several high-tech industries. Key applications include:
- Electrical Industry: High-frequency RF connectors, waveguide components, busbars, and power transmission cables where 101% IACS conductivity minimizes signal loss. Typical RF connectors achieve insertion loss below 0.1 dB at 10 GHz.
- Electronics: Semiconductor packaging, lead frames, and heat sinks for high-power devices requiring efficient thermal management. Heat sinks made from C10100 can dissipate up to 500 W/m² in forced convection systems.
- Telecommunications: Coaxial cables, antenna components, and microwave guides where low oxygen content prevents oxidation and maintains signal integrity. C10100 is specified for 5G base station components operating at 28 GHz.
- Aerospace: Cryogenic components, heat exchangers, and electrical contacts in satellites and spacecraft where reliability is critical. C10100 maintains ductility down to -269°C for liquid helium applications.
- Medical Devices: MRI magnet windings, surgical instruments, and implantable devices requiring non-magnetic properties and biocompatibility. C10100 meets ISO 10993 standards for medical device compatibility.
- CNC Machining Parts: Precision components such as connectors, terminals, and custom fittings for high-end audio equipment, laboratory instruments, and vacuum systems. Our customers report signal-to-noise ratios exceeding 120 dB in audio applications.
6. Why Choose Dongguan Stirling Metal Products Co., Ltd.
Dongguan Stirling Metal Products Co., Ltd. is a leading provider of C10100 oxygen-free copper materials and precision CNC machining services. With over 15 years of experience in the industry, we offer a comprehensive one-stop solution from material sourcing to finished parts. Our advantages include:
- ✅ Material Quality: We source C10100 from certified mills with full MTC (Mill Test Certificate) compliance to ASTM B152, ASTM F68, and ISO 9001 standards. Each batch is tested for oxygen content (<5 ppm) and electrical conductivity (≥101% IACS). Our in-house spectrometer verifies composition within 24 hours of receipt.
- ✅ CNC Machining Capabilities: Our facility is equipped with 5-axis CNC machines, Swiss-type lathes, and high-speed milling centers capable of achieving tolerances of ±0.005 mm and surface finishes down to Ra 0.1 µm. We maintain a Cpk of 1.67 for critical dimensions.
- ✅ Sample Making: Rapid prototyping with 3-5 day turnaround for complex geometries. We provide DFM (Design for Manufacturing) feedback to optimize your designs. Our engineering team reviews over 200 prototypes annually for C10100 projects.
- ✅ Batch Production: Scalable production from 100 to 100,000+ parts with consistent quality control using CMM (Coordinate Measuring Machine) inspection and SPC (Statistical Process Control). Our defect rate is below 50 ppm for production runs.
- ✅ Surface Treatment: In-house capabilities for polishing (mechanical and electrochemical), electroplating (silver, gold, nickel), passivation, and anti-tarnish coatings to meet specific application requirements. Our silver-plated C10100 components achieve 99.9% reflectivity for optical applications.
- ✅ Technical Support: Our engineering team provides material selection guidance, machining parameter optimization, and failure analysis to ensure your components perform reliably. We offer free consultation on cutting tool selection and coolant formulation.
For a Free Quote, please Contact Us! We offer competitive pricing, fast lead times, and global shipping. Let Dongguan Stirling Metal Products Co., Ltd. be your trusted partner for C10100 oxygen-free copper CNC machining solutions.
