2011-T3 Aluminum
A 2000-series Al-Cu alloy, the most machinable of the common aluminum alloys
Typical values for the temper in the title
2011 is an aluminum-copper alloy that also contains small amounts of lead and bismuth. These elements form soft particles in the metal that melt in the heat of cutting and break the chip into small pieces. The result: the most machinable of the common aluminum alloys.
It is the alloy of automatic lathes: screws, connectors and pins in large quantities, where cycle time and finish matter more than anything else. In the T3 temper its tensile strength is 370–405 MPa. The price: low corrosion resistance, no weldability, and the presence of lead.
Mechanical and physical properties
| Property | Value | Note |
|---|---|---|
| Tensile strength Rm | 370–405 MPa | |
| Yield strength Rp0.2 | 295–310 MPa | |
| Elongation A | 15% | |
| Hardness | 95–100 HB | |
| Modulus of elasticity E | 70 GPa | |
| Density ρ | 2.83 g/cm³ | |
| Machinability | 85% | relative rating in the site database |
Chemical composition (wt %)
| Element | Range | Role |
|---|---|---|
| Cu copper | 5.0–6.0 | gives the strength in heat treatment |
| Pb lead | 0.20–0.6 | chip breaker |
| Bi bismuth | 0.20–0.6 | chip breaker |
| Fe iron | max 0.7 | |
| Si silicon | max 0.40 | |
| Zn zinc | max 0.30 | |
| Others | max 0.05 each, 0.15 total | |
| Al aluminum | balance |
Common tempers
2011 is supplied mostly as drawn bar, in the T3 and T8 tempers.
| Temper | Properties | When to choose it |
|---|---|---|
| T3 | Rm 370–405 MPa, Rp0.2 295–310 MPa | solution treated, cold worked, naturally aged: the common temper |
| T8 | artificially aged | better dimensional stability and higher yield strength |
Applications
- High-volume parts on automatic lathes
- Screws, nuts and pins
- Connectors and small pipe fittings
- Parts for electronic and optical equipment
- Complex machined parts with a high finish
Fabrication
Machining
Excellent: short, broken chips, a high surface finish and high cutting speeds. That is the only reason to choose it, and in series production it justifies itself.
Welding
Not recommended: the lead and bismuth, together with the copper, cause hot cracking.
Corrosion and regulations
Low corrosion resistance, so it is protected by a coating or anodizing. Because of the lead, RoHS and similar regulations must be considered. Lead-free free-machining alternatives exist, such as 6026.
Compared with similar materials
| Material | Rm / Rp0.2 | Welding | When it is the better choice |
|---|---|---|---|
| 6262-T9 | 400 / 345 MPa | Good | a free-machining alternative from the 6000 series, with better corrosion resistance · material page |
| 2024-T4 | 470–480 / 325–345 MPa | Not recommended — Hot Cracking | when strength and fatigue resistance are needed, not only machinability · material page |
| 6061-T6 | 310 / 276 MPa | Good — ER4043 | when machinability matters less than corrosion resistance and weldability · material page |
Common mistakes
Choosing 2011 for a part that will be welded
The alloy does not weld. For a welded part, 6061 or 6082 is better.
Ignoring the lead
In products covered by RoHS or similar regulations, a leaded material may not comply. Check in advance or choose a lead-free alternative.
Leaving a part unprotected in a humid environment
The high copper lowers corrosion resistance. A coating or anodizing is needed.
Equivalents, standards and supply
| EN | 3.1655 |
|---|---|
| DIN | AlCu6BiPb |
| JIS | A2011 |
| Standards | ASTM B210 / EN 573-3 |
| Forms | rod · extrusion (turning only) |
| Producers | Aleris · Constellium · Hydro · Alcoa |
Learn more
Values are typical and for comparison only. For design, rely on the standard and on the mill certificate. Sources: Aluminum Association (composition), ASM and MatWeb data sheets, and the METAL HUB materials database.
Updated: October 31, 2026