ASTM B111 C71500 Copper Nickel Tubes
What is the 70/30 Copper?
C71500 (70/30) COPPER NICKEL has all the characteristics of C70600 (90/10) copper-nickel, but offers better corrosion resistance in high-velocity seawater. The operating temperature for C71500 (70/30) is also much higher than that of C70600 (90/10), which can assure a long and reliable service life for parts in these conditions. C71500 with its higher nickel content offers added corrosion resistance for critical marine hardware. C71500 Copper Nickel alloy conforms to specifications ASTM B171, ASME SB171, MIL-C-1726F, MIL-C-24679
copper nickel 70/30 chemical composition
Element | Cu | Ni | Fe | Mn | Other Impurities |
Content | Balance | 29.0–32.0% | 0.5–1.0% | 0.5–1.2% | Zn≤0.3%, Pb≤0.02% |
Mechanical Properties
| Grade | Formar | Tensile Strength,min | Yield Strength (0.2%Offset,min) |
| C71500 | annealed | ksi-52 | psi-18 |
Application
Heat exchangers for power plants
Steam Coils
Chemical and Petrochemical industries
Air Coolers / Oil Coolers / Hydrogen Coolers / Generator Coolers
Waste Heat Recovery
Air Perheaters / Air Conditioning / Air Heaters
Steam Condensers,etc
comparison of C71500 copper with other common copper-nickel alloy grades
| Property / Grade | C71500 (CuNi30) | C70600 (CuNi10) | C72200 (CuNi16Zn) | C71640 (Alloy 725) | Pure Copper (C11000) |
|---|---|---|---|---|---|
| Common Name | 70/30 CuNi | 90/10 CuNi | - | 66/30/2/2 CuNi | Electrolytic Tough Pitch (ETP) |
| Nominal Composition | Cu 70%, Ni 30%, Fe 0.5-1.0%, Mn 0.4-1.0% | Cu 88.6%, Ni 10%, Fe 1-1.8%, Mn 0.5-1.0% | Cu 82%, Ni 16%, Zn 0.5-1.0% | Cu 66%, Ni 30%, Cr 2%, Fe 2% | Cu 99.9%, O 0.04% |
| Key Characteristics | Excellent corrosion resistance in seawater, high strength, good ductility, biofouling resistance. | Good corrosion resistance, excellent formability, most common marine alloy. | Good corrosion resistance at lower cost, higher strength than C70600. | Superior corrosion resistance (especially to sulfide), very high strength. | Highest electrical & thermal conductivity, excellent ductility, poor corrosion resistance in seawater. |
| Typical Applications | High-stress marine components, condenser tubes, offshore platforms, seawater piping. | Standard for seawater condenser/heat exchanger tubes, ship hulls, desalination plants. | Heat exchanger tubes (freshwater/brine), plumbing, electrical connectors. | Aggressive environments (polluted/sewage water, high-velocity seawater). | Electrical wiring, busbars, heat sinks, roofing. |
| Relative Cost | High | Moderate | Moderate to High | Very High | Low |
| Corrosion Resistance (in seawater) | Excellent (Best in class) | Very Good | Good | Exceptional (Best overall) | Poor |
FAQ
Q: Is C71500 susceptible to stress corrosion cracking (SCC)?
A: C71500 has excellent resistance to stress corrosion cracking in marine environments, which is a key reason for its widespread use in critical seawater systems.
Q: What cleaning methods are recommended for C71500?
A: For routine cleaning, mild non-abrasive cleaners and fresh water rinses are sufficient. For removing oxide films or scale, diluted acids (like sulfamic or citric acid) can be used with proper procedures.
Q: Can C71500 be used in contact with sulfuric acid?
A: No, C71500 is not suitable for sulfuric acid service. It is primarily designed for neutral to alkaline saline environments. It has poor resistance to oxidizing acids and ammonia.
Q: What are the standard product forms available for C71500?
A: C71500 is commonly available as seamless and welded tubes, pipes, sheets, plates, forgings, and castings to meet various engineering needs.
Product Forms We Can Provide
| Product Category | Material Standards | Common Alloys | Key Specifications (Can be Customized) |
|---|---|---|---|
| Copper Tubes | ASTM B75, B88, B280,B111; EN 12449, 12451; DIN EN 12735; JIS H3300 | C10100 (OFE), C11000 (ETP), C12200 (DHP), C23000, C70600,C71500 | OD: 3mm - 300mm Wall Thickness: 0.5mm - 20mm Temper: Soft (O), Half-Hard (H50), Hard (H80) Form: Straight Lengths, Coils, U-Bends |
| Copper Sheets / Plates | ASTM B152, B248, B248M; EN 1652; DIN 1787; JIS H3100, H3250 | C10100 (OFE), C11000, C10200 (OF), C26000, C86200 | Thickness: 0.3mm - 100mm Width: Up to 1200mm Length: Up to 3000mm (or coils) Surface: Mill, Polished, Brushed |
| Copper Rods / Bars | ASTM B187, B301, B411; EN 12163, 12164; DIN 17672; JIS H3250 | C10100 (OFE), C11000, C14500, C36000, C63000 | Diameter/Rect. Size: 3mm - 300mm Shape: Round, Square, Hexagonal, Rectangular Condition: Drawn, Extruded, Hot Rolled |
| Copper Wires | ASTM B1, B2, B3, B258; EN 13601; IEC 60228; JIS H3100 | C10100 (OFE), C11000, C14420, C14500 | Diameter: 0.1mm - 20mm Temper: Soft, Annealed, Hard-Drawn Form: Bare, Tinned, Stranded, on Spools |
| Copper Foils / Strips | ASTM B103, B370; EN 1652; DIN 1787; JIS H3100 | C10100 (OFE), C10200, C11000, C19400, C26800 | Thickness: 0.02mm - 2.0mm Width: Up to 600mm Temper: Rolled, Annealed |
| CNC Machining Parts | As per Customer Drawing/Req. | All Common Copper Alloys (including C10100, C11000, C86200, etc.) | Process: Turning, Milling, Drilling, Tapping Tolerance: ±0.005mm - ±0.1mm Post-Processing: Deburring, Polishing, Plating |
Our factory
Our manufacturing facility operates a comprehensive and modern production line, equipped with advanced continuous casting, precision rolling, high-speed drawing, and multi-axis CNC machining centers, enabling us to process copper and copper alloys (such as C10100, C11000, C12200, C71500,C70600 etc.) into a full range of products including tubes, sheets, rods, wires, and foils. To ensure top-tier quality, we have implemented a rigorous in-process and final inspection system, utilizing state-of-the-art equipment such as spectrometers for material verification, digital tensile testers for mechanical property checks, precision dimensional gauges, and eddy current or ultrasonic testers for defect detection, guaranteeing that every product meets or exceeds international standards such as ASTM, EN, and JIS, as well as specific customer requirements.
Pre-shipment inspection
We provide engineering-grade protective packaging for each and every product. Whether it's heavy copper tubes and plates, or precision rods, wires, and ultra-thin foils, we employ multi-layer composite protection: the inner layer uses scratch-resistant PE film and custom padding for physical isolation and cushioning; the middle layer is treated with moisture-proof sealing and includes desiccants; the outer layer utilizes reinforced wooden crates or high-strength waterproof wrapping film, depending on the shape and weight, for stabilization and protection. This ensures that the products withstand moisture, oxidation, and impact during long-distance sea or land transportation, arriving in perfect condition at your site. In terms of delivery, we commit to efficiency and reliability: standard specification products can be prepared and shipped within 7-15 working days, while customized products will also enter production scheduling promptly. We maintain full transparency throughout the process, allowing you to precisely control timelines and ensure your project proceeds as planned.
