Aluminum alloys offer a myriad of possibilities in various industries, from aerospace to automotive and beyond. Understanding their behavior in bending operations and the role of tempers is crucial for achieving optimal results.
Aluminum alloys are prized for their versatility, lightweight nature, and corrosion resistance, making them ideal for a wide range of applications. From structural components to intricate designs, aluminum alloys offer unparalleled flexibility and durability.
Tempering Expectations: The Crucial Role of Tempers in Bending
Tempers play a pivotal role in determining the bendability of aluminum, with different alloys requiring specific tempers for optimal results:
Non-Heat-Treatable Alloys (3xxx and 5xxx series): The O-temper is preferred for bending, offering high formability without compromising strength.
Heat-Treatable Alloys (6xxx, 7xxx, and 2xxx series): Ideally bent in the T4 condition due to reduced yield strength, although natural aging may necessitate transitioning to the more challenging T6 temper for certain applications.
Understanding Aluminium Tempers and Their Impact on Bending
Aluminum temper refers to the material’s hardness and strength achieved through heat treatment and mechanical working. Different tempers significantly influence bending outcomes:
O (Annealed) Temper: Highly formable but lacks the strength for complex bends, making it suitable for simple bending operations.
H (Strain-Hardened) Tempers (e.g., H14 and H24): Strike a balance between formability and strength, allowing for moderate bends without cracking.
T (Thermal Treatment) Tempers (e.g., T6 and T651): Offer high strength and moderate formability, but require caution, especially for tight radii bends, to avoid cracking due to reduced ductility.
Choosing the Right Aluminum Alloy and Temper for Profile Bending
Selecting the appropriate alloy and temper is critical for both manufacturability and performance. Factors to consider include bending complexity, required strength, and environmental conditions:
- Simple Bends: Alloys from the 1xxx and 3xxx series in O or H14 temper suffice, prioritizing formability.
- Balanced Formability and Strength: The 6xxx series in H14 or H24 temper is commonly chosen.
- High Strength and Corrosion Resistance: The 5xxx series with appropriate tempers meets demands for strength and corrosion resistance in challenging applications.
- Aluminum alloys 6061 and 6082 are prized for their heat-treatable properties, boasting excellent elongation when annealed. However, as they transition to T4 and T6 tempers, their bendability diminishes. To optimize bending, starting in the T4 state and later transitioning to T6 through heat treatment is recommended.
By understanding the nuances of tempers and their impact on bending, manufacturers can make informed decisions to achieve optimal results in profile bending processes.
Aluminum Mechanical Properties
per The Aluminum Association, Inc.
| Alloy & Temper | Thickness | Tensile Strengths – ksi | ||||
| ULTIMATE | YIELD | Elongation % min in 2in or 4D | ||||
| Min | Max | Min | Max | |||
| 1100-H14 | .009-.012 | 16.0 | 21.0 | 14.0 | 1 | |
| .013-.019 | 16.0 | 21.0 | 14.0 | 2 | ||
| .020-.031 | 16.0 | 21.0 | 14.0 | 3 | ||
| .032-.050 | 16.0 | 21.0 | 14.0 | 4 | ||
| .051-.113 | 16.0 | 21.0 | 14.0 | 5 | ||
| .114-.499 | 16.0 | 21.0 | 14.0 | 6 | ||
| .500-1.00 | 16.0 | 21.0 | 14.0 | 10 | ||
| 3003-H14 | .009-.012 | 20.0 | 26.0 | 17.0 | 1 | |
| .013-.019 | 20.0 | 26.0 | 17.0 | 2 | ||
| .020-.031 | 20.0 | 26.0 | 17.0 | 3 | ||
| .032-.050 | 20.0 | 26.0 | 17.0 | 4 | ||
| .051-.113 | 20.0 | 26.0 | 17.0 | 5 | ||
| .114-.161 | 20.0 | 26.0 | 17.0 | 6 | ||
| .162-.249 | 20.0 | 26.0 | 17.0 | 7 | ||
| .250-.499 | 20.0 | 26.0 | 17.0 | 8 | ||
| .500-1.00 | 20.0 | 26.0 | 17.0 | 10 | ||
| 3105-H14 | .013-.019 | 22.0 | 29.0 | 18.0 | 1 | |
| .020-.031 | 22.0 | 29.0 | 18.0 | 1 | ||
| .032-.050 | 22.0 | 29.0 | 18.0 | 2 | ||
| .051-.080 | 22.0 | 29.0 | 18.0 | 2 | ||
| 5052-H32 | .017-.019 | 31.0 | 38.0 | 23.0 | 4 | |
| .020-.050 | 31.0 | 38.0 | 23.0 | 5 | ||
| .051-.113 | 31.0 | 38.0 | 23.0 | 7 | ||
| .114-.249 | 31.0 | 38.0 | 23.0 | 9 | ||
| .250-.499 | 31.0 | 38.0 | 23.0 | 11 | ||
| .500-2.00 | 31.0 | 38.0 | 23.0 | 12 | ||
| 5052-H34 | .009-.019 | 34.0 | 41.0 | 26.0 | 3 | |
| .020-.050 | 34.0 | 41.0 | 26.0 | 4 | ||
| .051-.113 | 34.0 | 41.0 | 26.0 | 6 | ||
| .114-.249 | 34.0 | 41.0 | 26.0 | 7 | ||
| .250-1.00 | 34.0 | 41.0 | 26.0 | 10 | ||
| 5052-H36 | .006-.007 | 37.0 | 44.0 | 29.0 | 2 | |
| .008-.031 | 37.0 | 44.0 | 29.0 | 3 | ||
| .032-.162 | 37.0 | 44.0 | 29.0 | 4 | ||
| 5052-H38 | .006-.007 | 39.0 | 32.0 | 2 | ||
| .008-.031 | 39.0 | 32.0 | 3 | |||
| .032-.128 | 39.0 | 32.0 | 4 | |||
| 5083-H116 | .063-.499 | 44.0 | 31.0 | 10 | ||
| .500-1.25 | 44.0 | 31.0 | 12 | |||
| 1.251-1.500 | 44.0 | 31.0 | 12 | |||
| 1.501-3.00 | 41.0 | 29.0 | 12 | |||
| 5086-H32 | .020-.050 | 40.0 | 47.0 | 28.0 | 6 | |
| .051-.249 | 40.0 | 47.0 | 28.0 | 8 | ||
| .250-2.00 | 40.0 | 47.0 | 28.0 | 12 | ||
| 5086-H116 | .063-.249 | 40.0 | 28.0 | 8 | ||
| .250-.499 | 40.0 | 28.0 | 10 | |||
| .500-1.25 | 40.0 | 28.0 | 10 | |||
| 1.251-2.00 | 40.0 | 28.0 | 10 | |||
| 5454-O | .020-.031 | 31.0 | 41.0 | 12.0 | 12 | |
| .032-.050 | 31.0 | 41.0 | 12.0 | 14 | ||
| .051-.113 | 31.0 | 41.0 | 12.0 | 16 | ||
| .114-3.00 | 31.0 | 41.0 | 12.0 | 18 | ||
| 5454-H32 | .020-.050 | 36.0 | 44.0 | 26.0 | 5 | |
| .051-.249 | 36.0 | 44.0 | 26.0 | 8 | ||
| .250-2.00 | 36.0 | 44.0 | 26.0 | 12 | ||
| 5454-H34 | .020-.050 | 39.0 | 47.0 | 29.0 | 4 | |
| .051-.161 | 39.0 | 47.0 | 29.0 | 6 | ||
| .162-.249 | 39.0 | 47.0 | 29.0 | 7 | ||
| .250-1.00 | 39.0 | 47.0 | 29.0 | 10 | ||
| 6061-T6 | .006-.007 | 42.0 | 35.0 | 4 | ||
| .008-.009 | 42.0 | 35.0 | 6 | |||
| .010-.020 | 42.0 | 35.0 | 8 | |||
| .021-.249 | 42.0 | 35.0 | 10 | |||
| 6061-T651 | .250-.499 | 42.0 | 35.0 | 10 | ||
| .500-1.00 | 42.0 | 35.0 | 9 | |||
| 1.001-2.00 | 42.0 | 35.0 | 8 | |||
| 2.001-4.00 | 42.0 | 35.0 | 6 | |||
| 4.001-6.00 | 42.0 | 35.0 | 6 | |||
Aluminum Chemical Composition
per The Aluminum Association, Inc.
| Grade | Si | Fe | Cu | Mn | Mg | Cr | Ni | Zi | Ti |
| 1100 | .095 Si + Fe | .05-.20 | .05 | 0.10 | |||||
| 3003 | 0.60 | 0.70 | .05-.20 | 1.0-1.5 | 0.10 | ||||
| 5052 | 0.25 | 0.40 | 0.10 | 0.10 | 2.2-2.8 | .15-.35 | 0.10 | ||
| 5083 | 0.40 | 0.40 | 0.10 | .40-1.0 | 4.0-4.9 | .05-.25 | 0.25 | 0.15 | |
| 5086 | 0.40 | 0.50 | 0.10 | .20-.7 | 3.5-4.5 | .05-.25 | 0.25 | 0.15 | |
| 5454 | 0.25 | 0.40 | 0.10 | .50-1.0 | 2.4-3.0 | .05-.20 | 0.25 | 0.20 | |
| 6061 | .40-.80 | 0.70 | .15-.40 | 0.15 | .80-1.2 | .04-.35 | 0.25 | 0.15 |
