Copper-Nickel Alloys (70/30 & 90/10) – Exotic
Metals
LLP
Commonly known as Cupro-Nickel, these alloys are the
industry standard for marine piping and desalination due to their immunity to
chloride stress corrosion.
Copper-Nickel Marine Grades
- 90/10 (C70600): The most common marine grade. It offers the best resistance to
biofouling (marine growth) and is highly ductile for easy fabrication into seawater
piping systems
- 70/30 (C71500 / C71520): Contains more nickel for higher strength and better
resistance to impingement corrosion from high-velocity seawater. C71520 is a
welding-grade variant with controlled impurities for superior joint integrity
Performance Comparison
| Property |
90/10 (C70600) |
70/30 (C71500) |
| Tensile Strength |
≥ 310 MPa |
≥ 360 MPa |
| Max Flow Velocity |
3.5 m/s |
4.0 m/s |
| Thermal Conductivity |
≈ 50 W/(m·K) |
≈ 29 W/(m·K) |
Brasses & Naval Alloys (C44300 / C46400)
These copper-zinc alloys are optimized for heat
exchangers and structural marine hardware.
Specialty Brass Marine Grades
- Admiralty Brass (C44300): A 70:30 brass with an addition of Arsenic to inhibit
"dezincification." It is primarily used for condenser tubes in power plants
- Naval Brass (C46400): A 60:40 "Muntz Metal" base with 1% Tin added to improve
corrosion resistance in seawater. It is significantly stronger than standard brass
and is used for marine shafts, propeller nuts, and turnbuckles
High-Strength Bronzes (Aluminium Bronze / NAB / C63000)
These alloys provide the strength of high-alloy steels
combined with the non-sparking and corrosion-resistant properties of copper.
Aluminium Bronze & Nickel Aluminium Bronze
- Aluminium Bronze: Contains 5–11% Aluminum. It forms a protective alumina film that
makes it incredibly resistant to cavitation and erosion
- Nickel Aluminium Bronze (NAB): An upgraded variant containing Nickel and Iron. It is
the premier material for submarine propellers, pump impellers, and heavy-duty marine
valves
- C63000 (Nickel Aluminium Bronze): A wrought version of NAB used for aerospace
bushings, landing gear components, and high-stress fasteners
High-Conductivity & Special Alloys (EC / ETP / Beryllium Copper)
Copper Grades & Applications
- EC Copper (Electrical Conductor): High-purity copper (99.9%) refined for maximum
electrical conductivity
- ETP Copper (C11000): "Electrolytic Tough Pitch." The standard for electrical
busbars, switches, and windings, offering 101% IACS conductivity
- Beryllium Copper (C17200): The "Super Alloy" of the copper family. When
age-hardened, it achieves a tensile strength of up to 1400 MPa—comparable to
high-strength tool steels—while remaining non-magnetic and non-sparking
aluminium-alloys-manufacturer-stockist-exporter-india.php
Weight Chart: Copper Alloy Round Bar (Theoretical kg/m)
| Diameter (mm) |
90/10 CuNi (Density 8.9) |
Naval Brass (Density 8.4) |
| 12 mm |
1.01 |
0.95 |
| 25 mm |
4.37 |
4.12 |
| 50 mm |
17.48 |
16.50 |
| 100 mm |
69.90 |
66.00 |
Product Availability for Exotic Metals LLP
- Tubes & Pipes: Seamless CuNi 70/30 & 90/10 (ASTM B111 / B466).
- Bars: Round, Square, and Hex bars in NAB and Beryllium Copper.
- Sheets: Large plates for tube sheets (ASTM B171) and marine hulls.
- Forgings: Custom-forged pump bodies and propeller hubs.
