UNS C71500 Copper Nickel Alloys

UNS C71500 Copper-Nickel alloys are used in areas where stainless steel cannot be used due to chloride stress-corrosion cracking and in other parts requiring high corrosion resistance. These alloys are also used as machined and forged valve and pump parts that are utilized for seawater services.

Boiler Parts

Condenser Components

Condenser Plates

Distiller Tubes

Evaporator Tubes

Ferrules

Heat Exchanger Components

Heat Exchanger Tubes

Process Equipment

Refrigerators

Welding Backing Rings

Fittings

Salt Water Piping and Fittings

Sea Water Condensers

Q1: C71500 vs C70600 – which one is used where stainless steel fails?

C71500 is used when stainless steel cannot be used due to chloride stress-corrosion cracking. The page states that UNS C71500 alloys are used in areas where stainless steel cannot be used due to chloride stress-corrosion cracking. C71500 contains 29-33% nickel, giving it immunity to chloride SCC. For seawater applications where 304 or 316 stainless steel would crack, choose C71500.

Q2: What forms of C71500 are available?

Pipe, tube, bar, rod, sheet, and plate are available. The page lists all these forms. For tube, specific tempers include OS025 (60 ksi tensile, 25 ksi yield) and OS035 (54 ksi tensile). For rod, H02 temper offers 75 ksi tensile with 70 ksi yield.

Q3: What is the density of C71500?

C71500 density is 0.323 lb/in³ at 68°F (8.94 g/cm³). For pipe weight calculation: (OD - wall) × wall × 10.68 = lb per foot. For metric: (OD mm - wall mm) × wall mm × 0.028 = kg per meter.

Q4: What Chinese grade is equivalent to C71500?

BFe30-1-1 is the Chinese equivalent grade. The page lists China BFe30-1-1 as the equivalent. UK equivalent is CN 107. EU equivalent is CuNi30Mn1Fe/CW354H.

Q5: What is the tensile strength of C71500 tube?

OS025 temper tube has 60 ksi tensile strength (typical). OS035 temper tube has 54 ksi tensile strength. Both have 45% elongation. For rod in H02 temper, tensile strength is 75 ksi. For flat products in M20 temper, tensile strength is 55 ksi.

Q6: What ASTM specifications cover C71500 tube?

ASTM B111, B359, B395, B466, B467, B543, B552, and B956 cover C71500 tube. ASTM B111 covers seamless condenser tubes. ASTM B359 covers integral fin tubes. ASTM B395 covers U-bend tubes. ASTM B466 covers seamless pipe and tube.

Q7: What are the applications of C71500?

Boiler parts, condenser components, condenser plates, distiller tubes, evaporator tubes, ferrules, heat exchanger components, heat exchanger tubes, process equipment, refrigerators, welding backing rings, fittings, salt water piping and fittings, and sea water condensers. The page lists all these applications.

Q8: What is the thermal conductivity of C71500?

Thermal conductivity is 17 Btu/(sq ft·ft·hr·°F) at 68°F. Electrical conductivity is 4.6% IACS at 68°F. Coefficient of thermal expansion (68-572°F) is 9 × 10⁻⁶ /°F. Specific heat capacity is 0.09 Btu/lb/°F at 68°F.

Q9: What is the melting point of C71500?

Liquidus is 2260°F, solidus is 2140°F. Modulus of elasticity in tension is 22,000 ksi. Modulus of rigidity is 8,300 ksi.

Q10: What is the hardness of C71500 different tempers?

OS035 tube: 36 HRF. OS025 tube: 45 HRB / 80 HRF. H02 rod: 80 HRB. M20 flat products: 35 HRB. These hardness values indicate the material condition and affect machinability and formability. Softer tempers (OS035) are easier to bend and expand.

Chemical verification: Each batch tested for Ni 29-33%, Fe 0.4-1.0%, Mn max 1.0%, Pb 0.05%, Zn 1.0%, Cu balance.

Mechanical testing: Tensile, yield, elongation, and hardness tested per temper: OS025 (60 ksi tensile, 25 ksi yield), OS035 (54 ksi tensile), H02 rod (75 ksi tensile, 70 ksi yield).

Dimensional inspection: OD, wall, length checked per applicable ASTM standards.

Traceability: Test reports linked to heat numbers.

Bundling: Pipes formed into bundles with steel straps, plywood separators between layers.

End protection: Plastic caps on both ends.

Labels: Alloy (C71500), heat number, size, length, quantity, PO number, net/gross weight.