What Are Aluminium Temper Designations?
Temper designations define the mechanical or thermal treatment condition applied to an aluminium alloy after production. These codes directly affect strength, formability, machinability and the final application area of the material.
- The T series is especially common in 2000, 6000 and 7000 series alloys.
- Cooling and ageing after extrusion define the profile temper.
- T4, T5, T6 and T651 are among the most common industrial designations.
Heat-Treatable Aluminium Alloys
Heat-treatable alloys are strengthened by heating, controlled cooling and ageing. 6000 series extrusion profiles, 2000 series high-strength parts and 7000 series aerospace/defence alloys are typical examples.
- T4: natural ageing with good formability.
- T5: cooling from production temperature and artificial ageing.
- T6: solution heat treatment and artificial ageing for maximum strength.
- T651: stress-relieved T6 condition.
| EN AW Code | Typical Application Area |
|---|---|
| T4 | Solution heat treatment + natural ageing. Suitable for profiles that will be bent or formed later. |
| T5 | Cooling from production temperature + artificial ageing. Extruded profiles are cooled and hardened in an ageing furnace. |
| T6 | Solution heat treatment + artificial ageing. Standard high-strength condition for structural profiles. |
| T651 | T6 + stress relief. Material is slightly stretched to reduce distortion during machining. |
Why Proper Alloy Selection Matters
Choosing the correct aluminium alloy directly affects strength, corrosion resistance, weldability, anodising quality, machinability and cost efficiency. Different EN AW designations in the same product form may significantly change product lifetime and service reliability.
Technical Evaluation with Kurtoglu Aluminium
Kurtoglu Aluminium supports material selection according to project requirements, including alloy, temper, surface condition and dimensions. Alternative material options can be evaluated according to operating conditions.