C10200 Oxygen-Free Copper Performance and Application

C10200 oxygen-free copper stands as a premier material in the realm of high-purity copper alloys, distinguished by its exceptionally low oxygen content (typically ≤0.001%) and superior electrical and thermal conductivity. This grade is indispensable in applications demanding minimal gas porosity, high ductility, and consistent performance under vacuum or hydrogen environments. At Dongguan Stirling Metal Products Co., Ltd., we leverage our deep expertise in CNC machining to transform C10200 into precision components that meet the most stringent engineering standards. With a purity level of 99.95% minimum copper and a controlled microstructure free from copper oxide inclusions, C10200 delivers unparalleled performance in high-tech industries ranging from semiconductor fabrication to aerospace propulsion systems.

1. C10200 Basic Information

C10200, also designated as OFHC (Oxygen-Free High Conductivity) copper, is a 99.95% pure copper alloy with a maximum oxygen content of 0.001%. Its unique microstructure, free from copper oxide inclusions, ensures exceptional electrical conductivity (101% IACS minimum) and thermal conductivity (391 W/m·K at 20°C). This material is ideal for applications requiring high vacuum integrity, such as electron beam welding chambers, klystrons, and superconducting magnet stabilizers. The absence of oxygen also prevents hydrogen embrittlement during brazing or welding, making it a preferred choice for hermetic seals in aerospace and semiconductor equipment. C10200 is produced through a controlled melting process under a reducing atmosphere or vacuum, which eliminates oxygen and minimizes other gaseous impurities. This results in a material with excellent formability, high ductility, and consistent mechanical properties across different tempers. The alloy is available in various forms including rod, bar, plate, sheet, and custom extrusions, with typical dimensions ranging from 1 mm to 300 mm in diameter for round bars and up to 600 mm in width for plates.

2. Chemical Composition

The precise chemical composition of C10200 is critical to its performance. The alloy is essentially pure copper with trace elements tightly controlled to maintain high conductivity and workability. The following table outlines the standard composition per ASTM B170 and CDA specifications:

Note: The balance is copper, with total impurities not exceeding 0.05%. The low oxygen content is achieved through a controlled melting process under a reducing atmosphere or vacuum, ensuring minimal oxide formation. Additional trace elements such as sulfur (S) are limited to ≤0.0015%, phosphorus (P) to ≤0.0005%, and selenium (Se) to ≤0.0002% to maintain high conductivity. The absence of deoxidizers like phosphorus or silicon distinguishes C10200 from other oxygen-free grades, ensuring maximum electrical performance.

3. Mechanical & Physical Properties

C10200 exhibits a unique combination of high ductility, moderate strength, and exceptional thermal/electrical properties. Its mechanical behavior is highly dependent on temper (annealed, half-hard, or hard). The following table provides comprehensive data for the annealed (O) and half-hard (H02) conditions:

The high electrical conductivity (101% IACS) makes C10200 ideal for current-carrying components, while its thermal conductivity (391 W/m·K) is approximately 10% higher than standard electrolytic tough pitch copper (C11000), enabling superior heat dissipation in high-power electronics. For the hard temper (H04), tensile strength can reach 400-450 MPa with elongation reduced to 5-10%, making it suitable for spring contacts and high-strength connectors. The material also exhibits excellent fatigue resistance, with an endurance limit of approximately 70 MPa at 10⁷ cycles in the annealed condition, and excellent creep resistance at temperatures up to 200°C.

4. CNC Machining Characteristics

Machining C10200 requires careful consideration of its high ductility and thermal conductivity. Unlike free-machining brasses (e.g., C36000), C10200 tends to form long, stringy chips that can cause tool wear and surface finish issues. However, with optimized parameters and tooling, excellent results are achievable. The following table summarizes recommended CNC machining parameters for C10200 in the annealed condition:

Key machining considerations:

• Chip Control: Use chip breakers or peck drilling cycles to prevent long, continuous chips that can wrap around tools. For turning, employ a 0.2-0.5 mm chip breaker groove on the insert.
• Tool Wear: Due to the material’s ductility, edge buildup is common. Use sharp, polished tools with positive rake angles (10-15°) and apply high-pressure coolant at 50-70 bar to flush chips away.
• Surface Finish: Achievable Ra values of 0.4-0.8 µm with finishing passes. For mirror finishes, use PCD tools with light cuts (0.1 mm depth) and high speeds (300-400 m/min). Typical surface roughness after roughing is Ra 1.6-3.2 µm.
• Heat Management: Despite high thermal conductivity, localized heating can occur at high feed rates. Maintain coolant flow at 10-20 L/min to prevent work hardening, which can increase hardness by 10-20 HV.
• Workholding: Use soft jaws or vacuum chucks to avoid marring the surface. For thin-walled parts (wall thickness <2 mm), consider cryogenic clamping with liquid nitrogen to minimize distortion, as thermal expansion can cause dimensional changes of 0.01-0.02 mm per 100 mm.
• Tool Life: Carbide tools typically achieve 30-60 minutes of cutting time before requiring regrinding, while PCD tools can last 200-500 minutes under optimal conditions.

5. Corrosion Resistance

C10200 exhibits excellent corrosion resistance in a wide range of environments due to the formation of a protective patina (copper oxide or basic copper carbonate). However, its performance varies with specific conditions:

• Atmospheric Environment: Excellent resistance in rural, industrial, and marine atmospheres. In coastal areas, a green patina forms within 5-10 years, providing long-term protection. Corrosion rates are typically <0.5 µm/year in rural areas and <2 µm/year in industrial zones.
• Fresh Water: Very good resistance in soft and hard water. Corrosion rates are typically <0.025 mm/year at ambient temperatures. Avoid stagnant water with high dissolved oxygen (>8 ppm), which can accelerate pitting corrosion at rates up to 0.1 mm/year.
• Seawater: Good resistance in clean seawater, with corrosion rates of 0.05-0.1 mm/year. However, C10200 is susceptible to pitting in polluted or stagnant seawater. Use cathodic protection (zinc or aluminum anodes) or coatings for long-term immersion. In flowing seawater (1-2 m/s), rates increase to 0.2-0.3 mm/year.
• Acids and Alkalis: General resistance to non-oxidizing acids (e.g., dilute HCl, H₂SO₄) at low concentrations (<10% by weight). Not recommended for oxidizing acids (e.g., HNO₃) or strong alkalis (pH>12), where corrosion rates can exceed 1 mm/year. In 5% H₂SO₄ at 25°C, the corrosion rate is 0.02 mm/year.
• Hydrogen Environment: Excellent resistance to hydrogen embrittlement due to the absence of oxygen. This makes C10200 ideal for hydrogen fuel cell components and high-pressure hydrogen storage systems up to 700 bar. No significant degradation observed after 1000 hours at 200°C in 100 bar H₂.
• Vacuum Applications: Outgassing rates are extremely low (<10⁻⁹ Torr·L/s·cm² after bakeout at 200°C for 24 hours), making it suitable for ultra-high vacuum (UHV) systems in particle accelerators and semiconductor fabrication. Total mass loss (TML) is <0.1% per ASTM E595.

6. Typical Applications

C10200’s unique properties enable its use in demanding applications across multiple industries:

• Electrical Industry: High-frequency coaxial cables (up to 100 GHz), waveguide components, busbars (rated for 1000-5000 A), commutators, and rotor windings for generators. Its high conductivity reduces I²R losses by 5-10% compared to C11000 in power transmission.
• Electronics & Semiconductor: Heat sinks for IGBT modules (thermal resistance <0.1°C/W), lead frames for power devices (thickness 0.1-0.5 mm), bonding wires (diameter 20-50 µm), and sputtering targets (purity 99.99%). The low oxygen content prevents void formation during soldering at 250-350°C.
• Aerospace & Defense: Radar components (waveguides for X-band and Ku-band), microwave tubes (klystrons with 10 MW peak power, magnetrons), and gyroscope parts. C10200’s dimensional stability under thermal cycling (ΔT=100°C) is critical for precision instruments, with thermal expansion coefficient of 17.0 µm/m·°C.
• Medical Devices: MRI cryostat components (operating at 4K), X-ray tube anodes (rotating at 3000-10000 rpm), and surgical instrument handles. Its biocompatibility (ISO 10993-5 tested) and antimicrobial properties (99.9% reduction of E. coli within 2 hours) are advantageous.
• Automotive: Battery terminals for electric vehicles (rated for 300-500 A continuous), heat exchangers for power electronics (cooling capacity 1-5 kW), and connectors for high-current systems (up to 200 A). C10200’s thermal conductivity reduces junction temperatures by 15-20°C compared to aluminum.
• CNC Machining Parts: Precision turned parts (e.g., nozzles, fittings, valve seats) requiring tight tolerances (±0.01 mm) and high surface finish (Ra 0.2 µm). Decorative items like jewelry and architectural trim also benefit from its luster, with mirror finishes achieving Ra <0.05 µm.

7. Why Choose Dongguan Stirling Metal Products Co., Ltd.

Dongguan Stirling Metal Products Co., Ltd. combines decades of metallurgical expertise with state-of-the-art CNC machining capabilities to deliver C10200 components that exceed industry standards. Our competitive advantages include:

• Material Traceability: Every batch of C10200 is sourced from certified mills (e.g., Aurubis, KME) and comes with full MTC (Mill Test Certificate) including chemical analysis and mechanical test results. We maintain ISO 9001:2015 certified quality management systems with 100% traceability from raw material to finished part.
• Precision Machining: Our 5-axis CNC centers (Mazak, DMG MORI) achieve tolerances of ±0.005 mm on critical dimensions. We use in-process probing (Renishaw OMP60) and CMM inspection (Zeiss Contura G2) to ensure 100% quality. Typical cycle times for complex parts range from 5-30 minutes.
• Surface Finishing: We offer electropolishing (Ra 0.1 µm), chemical brightening (gloss 90+ GU), and passivation to enhance corrosion resistance and aesthetics. Custom finishes like brushed (Ra 0.4 µm) or mirror (Ra <0.05 µm) are available. Our electropolishing process removes 10-20 µm of surface material to eliminate micro-cracks.
• Rapid Prototyping: Lead times of 3-5 days for prototypes using our in-house 3D printing (for patterns) and CNC turning centers. No minimum order quantity for samples. We can produce up to 50 prototypes per week with same-day quoting.
• Batch Production: For production runs (100-100,000 parts), we employ lean manufacturing principles with 7-15 day delivery. Our Kanban system ensures just-in-time supply for OEM customers. We operate 24/7 with 20 CNC machines dedicated to copper alloys.
• Technical Support: Our engineering team provides DFM (Design for Manufacturability) feedback, finite element analysis (FEA) for thermal management (using ANSYS), and material selection guidance. We offer free consultation on toolpath optimization, reducing cycle times by up to 30%.

Contact us today for a free quote on your C10200 CNC machining project. We guarantee competitive pricing (typically 10-20% below market rates for volumes >1000 parts), on-time delivery (98% on-time rate), and ISO 9001:2015 certified quality. Our dedicated project managers ensure seamless communication from prototype to production.