aluminum temper for 90 degree bending

Choosing the wrong aluminum temper for 90 degree bending leads to cracking. Aluminum does not behave like steel when bent. Select the wrong temper, and the outer radius of your bend cracks. Select the right one, and the bend is clean and strong.

Many focus only on the alloy—5052, 3003, 6061. But temper is equally critical. O, H14, and H32 are the three most common choices for 90-degree bends. Here’s how they compare and which one fits your job.

O Temper – Softest, Most Formable

O means annealed – fully soft. This temper gives you the highest ductility and the lowest strength. Bends with the tightest radius and almost never cracks.

Use O temper when:

– Deep drawing (depth greater than diameter) is required

– Extremely tight radius bends are needed

– Complex curved shapes are formed

The trade-off: Parts in O temper are soft and prone to deformation under load. If your finished part needs to hold a shape or carry weight, O temper may not work.

H14 Temper – Half-Hard, Balanced Performance

H14 is strain-hardened to about half-hard. It sits in the middle – moderate strength, good bendability. With sensible bend radii (typically greater than material thickness), 90-degree bends are reliable.

Use H14 temper for:

– General sheet metal work

– Light curving or shallow bends

– Architectural panels, trim, brackets

The limitation: H14 requires slightly larger radii than O temper, and its corrosion resistance is not as good as H32 in outdoor or wet environments.

H32 Temper – The Bending Workhorse

H32 is strain-hardened and stabilized. This temper offers medium strength with excellent formability. 5052-H32, in particular, is widely used for bent sheet metal parts.

Use H32 temper for:

– Enclosures, cabinets, and sheet metal housings

– Marine sheets, tanker trucks, pressure vessels

– Outdoor or corrosive environments (stabilization improves corrosion resistance)

Cracking risk is very low with H32, while the finished part retains enough strength for most structural needs. For everyday bending jobs, this is the safest bet.

Quick Comparison & Selection Guide

Simple selection rules:

– Need the tightest radius and strength is not a concern? → O

– Ordinary bends indoors with moderate strength? → H14

– Reliable 90‑degree bends with good strength and corrosion resistance? → H32

Also keep these practical points in mind:

– Bend radius is determined by the material – do not force a radius smaller than the minimum, or cracking is inevitable.

– Rolling direction affects cracking tendency; bending parallel to the rolling direction is safer.

– Aluminum springs back more than steel, and harder tempers spring back more – test bends help you compensate.

Three Common Misconceptions

1. “O temper is soft, so it’s always the safest.”  

O temper bends safely, but the finished part is weak. Many parts deform right after forming, let alone under service loads. Safety includes both bending and end‑use performance.

2. “H14 and H32 are interchangeable.”  

They differ in hardness. H14 is harder and requires larger radii; H32 is softer but more corrosion‑resistant. Choose based on your alloy and environment – do not swap them casually.

3. “Any H temper can bend 90 degrees.”  

The number after H indicates hardness level. H18 (full hard) cracks easily and is unsuitable for any bending. Only medium tempers like H14 and H32 are formable.

What Fits Your Application?

For most 90‑degree bending jobs, start with 5052‑H32 – it bends reliably, holds strength, and resists corrosion. If you need extremely tight radii and strength doesn’t matter, go with O temper. For general indoor sheet metal, H14 is a capable option.

Selecting the correct aluminum temper for 90 degree bending is straightforward once you match the temper to your forming requirements and service conditions.

Mingtai Aluminum supplies aluminum coils and sheets in all three tempers – O, H14, and H32 – with consistent quality and stable bending performance. We do not offer surface treatment or secondary processing, but we provide the right raw material for your bending needs.

FAQ

Q: Which temper is less likely to crack in a 90‑degree bend – H32 or H14?  

A: Both are fine with proper radii, but H32’s stabilized structure makes it the more reliable choice.

Q: Can I bend 6061‑T6 90 degrees without cracking?  

A: No – 6061‑T6 is too hard; you would need O temper or a very large radius.

Q: Does thicker aluminum need a larger bend radius?  

A: Yes – minimum bend radius is typically a multiple of thickness, so thicker sheets require proportionally larger radii.