Choose 6063 for architectural profiles, windows, doors, heatsinks and anything that needs a fine finish or a complex shape; choose 6061 (or 6005) when strength matters more, such as vehicle, structural and load-bearing parts. 6063 extrudes faster into thinner walls and anodises better; 6061-T6 is roughly 30–40% stronger.
| Property | 6063 | 6061 |
|---|---|---|
| Main alloying elements | Magnesium, silicon | Magnesium, silicon, copper |
| Typical tensile strength (T6) | about 205–240 MPa | about 260–310 MPa |
| Extrudability | Excellent, complex thin sections | Good, simpler sections |
| Surface / anodizing | Excellent | Good |
| Typical uses | Windows, doors, curtain wall, heatsinks, decoration | Vehicles, structures, machine parts, bicycles |
What about 6060 and 6005?
6060 is close to 6063 and common in Europe for architectural profiles. 6005 sits between 6063 and 6061 in strength and is popular for solar rails and vehicle profiles because it extrudes well and is strong.
How to choose
Start from the job: appearance and shape point to 6063; load and span point to 6061 or 6005. If unsure, send the drawing and the loads and we recommend the alloy and temper.
Questions
Is 6063 strong enough for windows?
Yes. 6063-T5 or T6 is the standard alloy for window, door and curtain wall profiles worldwide.
Can 6061 be anodised?
Yes, though 6063 gives a more even, decorative anodised finish.