Special bronze alloy grades are usually defined by some of the following national or international standards organizations:
ASTM International (American Society for Testing and Materials): Develops and publishes international standards for materials, products, systems and services, including copper alloys.
ISO (International Organization for Standardization): A global non-governmental organization responsible for developing and publishing international standards, including the classification and designation of copper alloys.
DIN (Deutsche Industrie Norm): Germany's national standards organization, which publishes standards for various materials, including copper alloys.
JIS (Japan Industrial Standards): Japan's national standards organization, which develops and publishes standards for materials, including copper alloys.
GB/T (China National Standard): China's national standards organization, which develops and publishes national standards, including the classification and alloy designation of copper alloys.
EN (European Standard): European standards jointly developed by CEN (European Committee for Standardization) and CENELEC (European Committee for Electrotechnical Standardization), covering materials such as copper alloys.
GOST (Russian State Standards): Russia's national standards organization, which publishes standards for various materials, including copper alloys.
BSI (British Standards Institution): The UK's national standards organization, although the UK has left the EU, BSI still participates in the development of international standards.
SAE (American Society of Automotive Engineers): Although mainly focused on the automotive industry, SAE also publishes material standards, including copper alloys.
UNS (Unified Numbering System): A material numbering system jointly developed by ASTM and SAE for the identification of standardized materials, including copper alloys.
These organizations ensure the consistency and traceability of materials through their standardization process, providing guidance and specifications for the production and use of materials around the world. Copper alloy alloy grades may vary from country to country, but the standards of these organizations enable international material exchange and trade.