A UK Defence Standard for CuNi30Cr2, which is a 70/30 cupro nickel containing 2 % Chromium and small additions of Zirconium and Titanium. The alloy is close in composition to the American alloy C71900. This alloy can be supplied in the wrought condition and has the highest corrosion resistance in sea water of all the copper based defence alloys.

Equivalent Specifications

Def Stan 02 824

Key Features

Def Stan 824 is a Copper Nickel Chromium alloy with the addition of silicon, manganese, iron, titanium zirconium. The alloy was developed by the MOD to replace Nickel Aluminium Bronze castings which on occasions suffered from selective phase corrosion.

This cast specification is now being manufactured in the wrought condition with enhanced properties – see our Elite Alloys section.

Typical Uses

Trials in submarine service over a period of 15 years has proved the excellent corrosion resistance of this alloy extending the service life of components.

The alloy has certainly fulfilled its potential, with excellent crevice corrosion measured at < 0.02mm per year and general corrosion at 0.02mm per year. The wrought properties will enable design engineers to consider a 60% increase in their design parameters giving scope to reduce the size and weight of components. The alloy has high strength and excellent toughness with impact values in excess of 100 Joules.

Description Copper Nickel Chromium
Nominal Composition CuNi30Cr2
Alloy Type cast

Typical Mechanical Properties

Tensile Strength (N/mm²) 480
Proof/Yield Strength (N/mm²) 300
Elongation (%) 15
Hardness Brinell 160
Impact Izod J20°C 130

Typical Physical Properties

Density g/cm³ 8.8
Melting Temperature Range °C 1180 - 1230
Thermal Conductivity W/mK 23
Electrical Resistivity μΩ.m15°C 35
Coefficient of Thermal Expansion 0-250°C 18
Relative Magnetic Permeability 1.01
Coefficient of Friction

Copper Alloys has the ability to modify existing alloys for improved performance. Many customers have benefited from this in the past.

To discuss your requirements, call a member of Copper Alloys’s technical team on +44 (0) 1782-816888, or email [email protected].

Contact

+44 (0) 1782 816888

[email protected]

Auckland Street, Stoke-on-Trent, ST6 2AZ, United Kingdom