Copper and Copper Alloys - Aluminium Bronze - Def-Stan 02-833 ~ NES833 ~ CW307G

Def-Stan 02-833 ~ NES833 ~ CW307G

Bronzes are Copper-based alloys with the major alloying element being Tin. They offer a combination of properties such as high strength, hardness, corrosion resistance and wear resistance.
Copper-Aluminium alloys are commonly known as Aluminium Bronzes. These alloys are a range of Copper-based alloys in which the primary alloying element is up to 14% Aluminium. The four major groups of Aluminium Bronze are:

~ Single phase alloys containing less than 8% of Aluminium.
~ Two-phase (duplex) alloys containing 8 to 11% Aluminium. These alloys also frequently have additions of Iron and Nickel to increase strength. This group’s contains casting alloys AB1 and AB2, the wrought alloys CA105, CA104 and Defence Standard alloys (formerly Naval Engineering Standard, NES - NES 747 when cast and the wrought form NES 833).
~ The low magnetic permeability Aluminium-Silicon alloys.
~ The Copper-Manganese-Aluminium alloys with good castability.

Alloy Defence Standard (NES) 833 is an Aluminium Bronze with good ductility and impact strength. It also has superior corrosion resistance.

Aluminium Bronze to Defence Standard (NES) 833 is typically used in:
~ Marine Valves
~ Pumps
~ Weapons handling systems
~ Fasteners
~ Gears
~ Marine propeller shafts

Chemical Composition


Chemical Element % Present
Iron (Fe) 4.20 max
Aluminium (Al) 9.30 max
Manganese (Mn) 0.30 max
Nickel (Ni) 4.20 max
Copper (Cu) Balance


Physical PropertyValue
Density 7.5 g/cm³
Thermal Conductivity 42 W/m.K
Electrical Resistivity 0.172 x10^-6 Ω .m



Mechanical PropertyValue
Proof Stress 400-530 MPa
Tensile Strength 600-760 MPa
Elongation A50 mm 15-5 %
Hardness Vickers 170-220 HV

Alloy Designations

Def-Stan (NES) 833 corresponds to the following designations:


NES 833

DGS 1043

CW307G (not an exact equivalent)

Supplied Forms

Defence Standard (NES) 833 is typically supplied as Round Rod

  • Bar
  • Rod

Corrosion Resistance

Defence Standard (NES) 833 has high corrosion resistance, particularly in marine environments.

It is immune to chloride stress corrosion cracking.

This alloy also has excellent resistance to cavitation erosion.

Temperature Resistance

Defence Standard (NES) 833 largely retains its strength and hardness up to 400°C.

It is also resistant to high temperature scaling at up to 1000°C


Defence Standard (NES) 833 is fully weldable by common welding methods.


Machinability is poor rated at 30 compared to Brass CZ121 / CW614N which is rated as 100.

Datasheet Search

Last Datasheet Revision

18 July 2019


This Data is indicative only and as such is not to be relied upon in place of the full specification. In particular, mechanical property requirements vary widely with temper, product and product dimensions. All information is based on our present knowledge and is given in good faith. No liability will be accepted by the Company in respect of any action taken by any third party in reliance thereon.

Please note that the 'Datasheet Update' date shown above is no guarantee of accuracy or whether the datasheet is up to date.

The information provided in this datasheet has been drawn from various recognised sources, including EN Standards, recognised industry references (printed & online) and manufacturers’ data. No guarantee is given that the information is from the latest issue of those sources or about the accuracy of those sources.

Material supplied by the Company may vary significantly from this data, but will conform to all relevant and applicable standards.

As the products detailed may be used for a wide variety of purposes and as the Company has no control over their use; the Company specifically excludes all conditions or warranties expressed or implied by statute or otherwise as to dimensions, properties and/or fitness for any particular purpose, whether expressed or implied.

Advice given by the Company to any third party is given for that party’s assistance only and without liability on the part of the Company. All transactions are subject to the Company’s current Conditions of Sale. The extent of the Company’s liabilities to any customer is clearly set out in those Conditions; a copy of which is available on request.