Standards are important because they form a common language between producers, stockists and users of copper alloys. It is important to have the facility to compare the old British, European, American and Japanese Standards.
UK and European Standards
Copper 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 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 In most cases, these have been replaced by European Standards (EN) which will apply in other CEN Member countries.
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 USA, it is essential to find a UK or European material designation which is equivalent to an existing American material designation. See Copper Key below.
The below text is the introduction to Publication 120 ‘Copper and Copper Alloys – Compositions, Applications and Properties’.
The EN Standards
The EN series of standards for copper and copper alloys offers 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. Commencing in the late 1980s, drafting of European Standards for Copper and Copper Alloys became a major activity for national standards’ organisations and their industrial partners. Because 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 EN standards are more complex than the old BS standards. Furthermore, the EN standards tend to cover narrower fields than BS standards; hence there are more alloys in the EN series than in the old BS standards. BS EN standards are the British adoption of the EN standards (see BS EN to BS comparison table).
Publication 120 summarises the main compositions and gives some idea of mechanical properties. For full details of products and mechanical properties refer to the standards documents obtainable from:
The British Standards Institution
398 Chiswick High Road
London W4 4AL
Tel: 020 8996 9001
Fax: 020 8996 7001
Defence Standards (DStan)
These standards are sponsored by the Ministry of Defence and include 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.
The standards explain the various classes required in service (for example, on a submarine) and include details of the mandatory, non-destructive testing by ultrasonic, dye penetrant and X-ray methods.
The DStan specifications were formerly designated Naval Engineering Standards (NES).
For further details of DStan, visit www.dstan.mod.uk.
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:
B16 is an ASTM specification for free cutting brass rod and bar.
TUNGUM is a trade name for aluminium-nickel-silicon-brass. CZ127 (CW700R).
BS S 369:1963 5 per cent phosphor bronze (copper-tin-phosphorus) rods and sections (other than forging stock) withdrawn and replaced by:
BS 2874:1969 Specification for copper and copper alloys. Rods and sections (other than forging stock) withdrawn because requirements were included in:
BS 2874:1986 Specification for copper and copper alloy rods and sections (other than forging stock) withdrawn and replaced by:
BS EN 12163:1998 Copper and copper alloys. Rod for general purposes and
BS EN 12164:1998 Copper and copper alloys. Rod for free machining purposes and
BS EN 12167:1998 Copper and copper alloys. Profiles and rectangular bar for general purposes
The standards in bold are current.
This is an Aerospace spec. “Brass bars suitable for brazing or silver soldering 1917. It was withdrawn and replaced by BS2B11 1930 which became BS3B 1933 which was withdrawn in 1990 and not replaced. The most appropriate spec. to consult is BS EN 1044:1999 “Specification for filler metals for brazing”.
Yes, in the EN specification the properties are quoted separately for continuous cast (GC) and centrifugally cast (GZ) conditions.
Heat to 450oC for one hour and air cool. This should be agreed between you and the manufacturer when ordering.
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.
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.
EN 1254 Parts 1 to 5.
This is an old CDA Inc (USA) spec. It is now ASTM 36000. The UK equivalent is CW603N (CZ124)). It is a free machining brass.