7xxx · Zinc alloy
7005 aluminium — composition, properties and extrusion notes
A weldable high-strength alloy — the classic bicycle frame material.
How it compares
Relative to the other grades we extrude. This is a selection aid, not a specification.
Mechanical properties
| Temper | Tensile (MPa) | Yield (MPa) | Elongation (%) | Hardness (HB) |
|---|---|---|---|---|
| T6 | 350 | 290 | 12 | 120 |
| T53 | 345 | 290 | 11 | 115 |
Typical values for extruded product. Minimum guaranteed values depend on temper and product form — the mill certificate governs.
Composition limits
| Element | Limit (%) |
|---|---|
| Si | 0.35 |
| Fe | 0.40 |
| Cu | 0.10 |
| Mn | 0.20–0.70 |
| Mg | 1.0–1.8 |
| Cr | 0.06–0.20 |
| Zn | 4.0–5.0 |
| Ti | 0.01–0.06 |
| Zr | 0.08–0.20 |
| Al | remainder |
Single figures are maxima; ranges are the permitted window.
Working with this alloy
- Density
- 2.78 g/cm³
- Common tempers
- T53, T6, T63
Physical properties
| Property | Value |
|---|---|
| Thermal conductivity | 130 W/m·K |
| Melting range | 600–643 °C |
| Electrical conductivity | 34 % IACS |
When to use it
Unusual among the 7xxx grades in that it is genuinely weldable, which is why it dominates cycle frames. Anodising is possible but the colour response is less predictable than 6xxx.
Typical applications
- Bicycle and e-bike frames
- Scooter decks and sports equipment
- Tennis and badminton rackets
- High-strength welded structures
Other alloys
1060
99.6% pure aluminium for conductivity, ductility and chemical resistance.
1100
99.0% pure aluminium — the workhorse of the commercially pure grades.
3003
Manganese-bearing alloy — about 20% stronger than 1100 with similar workability.
5052
The strongest common non-heat-treatable sheet alloy, and the marine standard.
6005A
A stronger structural alternative to 6063, developed for extruded transport profiles.