Several systems of aluminum standards exist for identifying and designating aluminum alloys and for specifying their properties. Understanding these aluminum standards is essential for selecting, comparing, and cross-referencing alloys across different regions and industries.
As with other metals, the most prominent aluminum standards include the European EN (Euronorm), the US SAE and ASTM, the Japanese JIS, and the international ISO systems. The BRIC countries also maintain their own standards: the Chinese GB and YB, the Indian IS, the Brazilian NBR, and the Russian GOST.
Euronorm aluminum standards use four digits to identify wrought alloys and five digits to identify cast alloys. They are broadly the same as the ISO aluminum standards and the US numerical method of identification, in which a four-digit number provides the unique alloy designation. This approach aligns with the International Designation System issued by The Aluminum Association in the USA. The Aluminum Association (AA) system is specific to aluminum and serves as the basis for aluminum standards and designations worldwide. For example, the chemical composition limits specified in the Euronorm aluminum standards are identical to those registered with the Aluminum Association for the equivalent alloys.
Table 1. Global Aluminum Standards Comparison
Standard
Region / Organization
Primary Purpose
Typical Prefix / Format
Example
AA
Aluminum Association (USA)
Aluminum alloy designation
4-digit designation
6061
ASTM
ASTM International
Material specifications and testing
ASTM B221
SAE
SAE International
Aerospace and automotive specifications
SAE AMS
AMS 4027
EN
Europe (CEN)
European alloy designation and specifications
EN AW-6061
ISO
International Organization for Standardization
International standards
ISO 209
JIS
Japan
Japanese Industrial Standards
JIS H4040
GB
China
Chinese National Standards
GB/T
GB/T 3190
YB
Metallurgical industry standards
YB/T
IS
India
Bureau of Indian Standards
IS 737
GOST
Russia
National standards
GOST 4784
NBR
Brazil
Brazilian standards
ABNT NBR
NBR 6834
A prefix is used to indicate the governing standard—AA for the Aluminum Association or EN AW for the European aluminum standards. Within the European system, the prefixes carry specific meanings: "AB" denotes ingots for remelting, "AC" denotes a cast product, "AM" denotes a cast master alloy, and "AW" denotes a wrought product, as in EN AW-1050. A suffix "A" indicates a national variation of the alloy, as in EN AW-6005A.
In the AA aluminum alloy designations, four numeric digits are used. The first digit identifies the principal alloying constituent (or constituents). The second and third digits provide the specific alloy designation; this number has no inherent significance but is unique to each alloy. The fourth digit indicates whether the product is a casting (0) or an ingot (1 or 2).
Another widely used classification system is the Unified Numbering System (UNS), which has the advantage of covering all metallic alloy systems. For aluminum alloys, the UNS is essentially an adaptation of the Aluminum Association designation system to fit the UNS format.
A UNS number is created by taking the three digits to the left of the decimal point in the Aluminum Association system and adding the prefix "A9" (meaning aluminum alloys), followed by a digit that reflects any letter prefix in the alloy designation. For alloys with no letter prefix, the next digit after A9 is 0; for those with an A, the next digit is 1; for B, it is 2; and so on. For example, in the UNS system, 356.0 becomes A90356, A356.0 becomes A91356, and C356.0 becomes A93356.
This article covers the global standards that govern aluminum alloy designation. The other guides in the Aluminum series address what those standards define. Aluminum Specifications explains the four-digit designation and temper system in detail, while Aluminum Grades shows how the alloys are organised into series by their principal alloying element. Aluminum Properties covers the mechanical, physical, and performance characteristics that distinguish one alloy from another. Together, they connect the standards framework with the designations, grades, and properties it underpins.
The most prominent aluminum standards are the European EN (Euronorm), US SAE and ASTM, Japanese JIS, and international ISO systems, along with the BRIC standards: Chinese GB and YB, Indian IS, Brazilian NBR, and Russian GOST.
It is an aluminum-specific system that uses four numeric digits to identify alloys. The first digit indicates the principal alloying element, the second and third digits give the unique alloy designation, and the fourth digit shows whether the product is a casting or an ingot. It serves as the global basis for aluminum standards and designations.
Euronorm standards use four digits for wrought alloys and five digits for cast alloys, along with prefixes such as EN AW for wrought products and EN AC for cast products. A suffix "A" indicates a national variation of the alloy.
The UNS is a classification system covering all metallic alloys. For aluminum, it adapts the Aluminum Association designation by adding an "A9" prefix and a digit reflecting any letter prefix. For example, 356.0 becomes A90356 and A356.0 becomes A91356.
Yes. The chemical composition limits specified in the Euronorm aluminum standards are identical to those registered with the Aluminum Association for the equivalent alloys.