Standards for Coppers and Copper Alloys

Standards for coppers and copper alloys are important because they define material requirements—such as composition, mechanical and metallurgical properties—so that materials can be ordered and supplied with confidence, from any reputable supplier.

Standards cover material designations (compositions) and product forms—rolled flat, tube, rod/bar profiles and wire, and forging stock/forgings. Product standards define compositions, property requirements, tolerances, sampling procedures, conformity verification test methods and delivery conditions.

There are different standards systems in place in different regions and it is often necessary to be able to compare these (e.g. European, old British, American and Japanese Standards) and find equivalents.

CDA provides the information to enable users to do this, through this website, its publications and its online enquiry service.

This section provides an overview of standards plus detailed information tables covering those applicable in the UK, with links to the relevant full standards. CDA recommends that the standards are consulted for full information on any coppers or copper alloys.

UK and European Standards

Coppers and copper alloys, like other materials, are covered by standards. The use of standards is essential in the proper definition of the type, form and condition of an alloy. Standards form part of the technical language used in communication between producers of alloys, manufacturers, designers and stockists and any technical person concerned with materials usage. It is not sufficient to define an alloy by its common name, such as ‘brass’ or ‘bronze’. For many years, copper alloys have been covered by British Standards (BS). In most cases, these have been replaced by European Standards (EN) which will apply in other CEN Member countries.

The EN series of designations for coppers and copper alloys offer a selection of materials to suit a very wide variety of end uses. They represent a consensus agreement on those most frequently ordered by consumers. As a large number of national preferences have needed to be taken into account against the background of a pan-European agreement to develop tight product standards, the European Standards are more complex than the old British Standards. Furthermore, the European Standards tend to cover narrower fields than British Standards; hence there are more alloys in the EN series than in the old BS series. BS EN is the British adoption of the EN standards (see BS EN to BS comparison table).

Two further specialised and more exacting series of material standards apply in the UK: Defence Standards (Def Stan) and British Standard Aerospace Series (BS B).

Defence Standards (Def Stan)

These standards are sponsored by the Ministry of Defence and include specifications for aluminium bronzes, aluminium silicon bronzes and copper-nickels used in demanding military applications, where high fracture toughness, low magnetic permeability and excellent corrosion resistance are required. Def Stan were formerly designated as Naval Engineering Standards (NES).

The standards relate to classes of vessel and include details of mandatory, non-destructive testing by ultrasonic, dye penetrant and X-ray methods.

For details of Def Stan for copper alloys, view a summary of applicable standards or visit the Defence Standards Portfolio (registration required).

British Standard Aerospace Series

These standards are based on current EN or old BS material designations but were developed to meet the more exacting requirements of the aerospace industry—enhanced mechanical properties and tighter compositional limits.

Visit the BS Aerospace Series standards page to view titles and scope.

The information presented on this website summarises the main compositions and provides typical mechanical properties and uses.

UK Copper and Copper Alloy Designations and Standards (BS EN, old BS, Def Stan, BS B)

Information Tables

American Standards (ASTM)

Americans are not usually familiar with British or European Standards. They use the UNS (Unified Numbering System) which is the accepted alloy designation system in North America for wrought and cast copper and copper alloy products—it is managed by ASTM and SAE. When manufacturing for the US, it is essential to find a UK or European material designation which is equivalent to an existing US material designation. See Copper Key below.

Copper Key Software

Copper Key’ is software which enables users to find the nearest equivalent designations for EN, old BS, US (ASTM), German (DIN), Japanese (JIS) and Chinese (GB) copper and copper alloys. The software allows users to compare compositions of equivalent designations and see which national standards apply.

This software provides an essential introductory cross-reference tool for designers and specifiers but, for full details on properties and special requirements, such as non-destructive testing, heat treatment or cleaning, the relevant standards, obtainable from BSI or other national standards bodies, should be consulted.

The software was developed by CDA’s sister organisation in Germany, Deutsches Kupferinstitut, and is available to use, free of charge, online.

National Standard Bodies

Here is a selection of national standard bodies:

Country Acronym Website
Australia SA
Austria ASI
Belgium NBN
Czech Republic UNMZ
France Afnor
Germany DIN
Italy UNI
Japan JI|S
Russia GOST R



A drawing refers to a material as B16. What is this?

B16 is an ASTM specification for free cutting brass rod and bar.

A drawing specifies TUNGUM for a pipe. What is TUNGUM?

TUNGUM is a trade name for aluminium-nickel-silicon-brass. CW700R (CZ127).

Can you help me with an old brass specification BS 369?

BS 369: 5 per cent phosphor bronze (copper-tin-phosphorus) rods and sections (other than forging stock) was withdrawn and replaced by:

BS 2874: Specification for copper and copper alloy rods and sections (other than forging stock) was withdrawn and replaced by:

BS EN 12163: Copper and copper alloys. Rod for general purposes and
BS EN 12164: Copper and copper alloys. Rod for free machining purposes and
BS EN 12167: Copper and copper alloys. Profiles and rectangular bar for general purposes.

The standards in bold are current.

Copper tube for water and gas in sanitary and heating applications used to be manufactured to BS 2871 Part 1. What is the number of the current European Standard for copper tubes?

The number of the current European Standard for copper tubes is BS EN 1057.

Could you please identify an old brass specification BS B 11?

‘BS B’ is an Aerospace spec for copper alloys. BS B 11 is ‘Brass bars suitable to be brazed or silver soldered’. BS B 11 was withdrawn in 1990 and not replaced. Brass bars are now specified in BS EN 12167.

Is there a difference in properties between continuous cast versus centrifugally cast aluminium bronze?

Yes, in the EN specification the properties are quoted separately for continuous cast (GC) and centrifugally cast (GZ) conditions.

We have purchased castings in CC333G (AB2). The standard BS EN 1982:2008 suggests in Annex A, clause A6, a stress relief heat treatment, but gives no details. Do you have a recommendation?

Heat to 450oC for one hour and air cool. This should be agreed between you and the manufacturer when ordering.

What does the term DEF STAN (DStan) mean?

These are the engineering standards prepared for material for use by the Ministry of Defence. They have replaced NES (Naval Engineering Standards), which in their turn replaced DGS (Directorate General Ships) standards.

What is temper as applied to copper and copper alloys?

Strength and hardness increases with the percentage of cold reduction after hot working. Properties are defined in standards. See also CDA publications in the Resource Library.

What is the British Standard for the design and installation of domestic sprinkler systems?

The British Standard for the design and installation of domestic sprinkler systems is BS 9251.

What is the current standard for copper fittings?

The current standard for copper fittings is BS EN 1254 Parts 1 to 5.

A specification describes a brass as CDA 360. What is this?

This is an old CDA Inc (USA) spec—it is now UNS C36000. The UK equivalent is CW603N (CZ124) and is a free machining brass.

Compare compositions of equivalent designations in different national standards.