EN Standards for Aluminum Extrusions

Key EN Standards for Aluminum Extrusions

Differences Between BS1474 and EN Standards

For those who are familiar with the old BS1474 standard, here are the primary differences when transitioning to the new EN standards:

• Chemical Composition: No changes have been made to chemical composition guidelines.
• Alloy Numbering System: The numbering system remains unchanged.
• Temper Designations for Heat-Treatable Alloys: A wider range of special tempers is now available, with up to four digits following the “T” to accommodate non-standard applications (e.g., T6151).
• Temper Designations for Non-Heat-Treatable Alloys: Existing tempers remain the same, but a more comprehensive explanation of how they are achieved is provided. The “O” (soft) temper is now classified as H111, and a new intermediate temper, H112, has been introduced. For alloy 5251, tempers are now listed as H32, H34, H36, and H38 (previously H22, H24, etc.).

For complete information on chemical compositions and mechanical properties, please refer to the datasheet entitled “Aluminum Specifications.”

Alloy Groups

For the purposes of tolerances and mechanical properties, aluminum alloys are divided into two groups:

• Group I: Includes the 1000, 3000, and 6000 series alloys, as well as 5005, 5051, and 5251.
• Group II: Includes the 2000 and 7000 series alloys, as well as 5052, 5154, 5454, 5754, 5083, and 5086.

Alloy Group I

This group includes the following alloys:

• 1050, 1070, 1200, 1350 (pure aluminum for electrical and chemical applications)
• 3003, 3102, 3103 (manganese-alloyed aluminum for HVAC and general engineering applications)
• 5005, 5005A, 5051A, 5251 (magnesium-alloyed aluminum for marine and structural applications)
• 6000 Series: Includes alloys such as 6101, 6005, 6061, 6063, 6082 (balanced for strength, formability, and weldability, widely used in construction and automotive sectors).

Alloy Group II

This group includes:

• 2000 Series: 2007, 2011, 2014, 2024 (copper-alloyed aluminum for aerospace and high-performance engineering applications)
• 5000 Series: 5052, 5154, 5083, 5086 (magnesium-alloyed aluminum with excellent corrosion resistance, used in marine and heavy-duty industries)
• 7000 Series: 7003, 7075, 7020 (zinc-alloyed aluminum known for high strength, commonly used in aerospace and high-performance applications).