Aluminum 2A06-O (Annealed)
Temper
GB 2A06
Choose the annealed condition for deep cold forming and bending or as feedstock before solution treatment and ageing; tensile is only 220 MPa at 18% elongation.
Values for the O condition
Other 2A06 tempers and conditions
2A06 is listed in 5 conditions; see the grade overview at 2A06.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
OThis page Annealed | Choose the annealed condition for deep cold forming and bending or as feedstock before solution treatment and ageing; tensile is only 220 MPa at 18% elongation. | 110 | 220 | 18 | 55 HB | 48 % IACS |
T3, stress relieved by stretching | Choose for machined thick plate and bar: stretching after solution treatment relieves residual stress, so parts stay dimensionally stable after heavy cutting. | 310 | 450 | 12 | 118 HB | 30 % IACS |
T4Default Solution heat treated and naturally aged | Pick the solution treated and naturally aged default for riveted structures and skins, balancing 460 MPa tensile, 12% elongation and fatigue performance. | 320 | 460 | 12 | 120 HB | 30 % IACS |
T6, heat treated by the user | Specify when complex sheet-metal or machined parts are solution treated and artificially aged after forming, giving 390 MPa yield with 7% elongation. | 390 | 470 | 7 | 132 HB | 36 % IACS |
Solution heat treated and artificially aged | Use solution treated and artificially aged stock when 400 MPa yield and heat resistance to 175 °C matter more than ductility (8%) and fracture toughness. | 400 | 480 | 8 | 135 HB | 36 % IACS |
What is 2A06-O?
2A06-O is 2A06 in the O temper — choose the annealed condition for deep cold forming and bending or as feedstock before solution treatment and ageing; tensile is only 220 MPa at 18% elongation. 2A06-O has a yield strength of 110 MPa (16 ksi) and a tensile strength of 220 MPa (31.9 ksi) — weaker than 81% of aluminum grades. Elongation at break is 18% and the elastic modulus is 71 GPa (10.3 Msi). 2A06-O has a density of 2.77 g/cm³ (0.1 lb/in³), heavier than 71% of aluminum grades. It melts at 505°C (941 °F). T4 is the default condition FabDigit quotes; O is available on request or by drawing note.
Advantages
- Conducts heat well — 190 W/m·K (109.8 BTU/hr·ft·°F), better than 89% of aluminum grades
- High electrical conductivity — 48 % IACS, better than 88% of aluminum grades
- Ductile — tolerates forming and impact — 18%, better than 86% of aluminum grades
- Forms and bends easily — 75/100, better than 86% of aluminum grades
- Tough — resists crack growth — 32 MPa·√m (29.1 ksi·√in), better than 83% of aluminum grades
Limitations
- High embodied carbon — 16 kg CO₂/kg, worse than 98% of aluminum grades
- Difficult to weld — 20/100, worse than 89% of aluminum grades
- Needs corrosion protection — 35/100, worse than 85% of aluminum grades
- Low strength — 110 MPa (16 ksi), worse than 81% of aluminum grades
2A06-O properties
Typical room-temperature values for 2A06-O; 12 are specific to this condition. Other listed values are 2A06 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
2A06-O has a density of 2.77 g/cm³ (0.1 lb/in³), heavier than 71% of aluminum grades. It melts at 505°C (941 °F).
Mechanical13
2A06-O has a yield strength of 110 MPa (16 ksi) and a tensile strength of 220 MPa (31.9 ksi) — weaker than 81% of aluminum grades. Elongation at break is 18% and the elastic modulus is 71 GPa (10.3 Msi).
Thermal6
2A06-O is rated for continuous service to 150°C (302 °F). It conducts heat at 190 W/m·K (109.8 BTU/hr·ft·°F), better than 89% of aluminum grades. Thermal expansion is 22.8 µm/m·K (12.7 µin/in·°F).
Electrical3
2A06-O conducts electricity at 48 % IACS, better than 88% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (35/100), worse than 85% of aluminum grades.
Sustainability4
Producing a kilogram of 2A06-O takes about 210 MJ of energy and emits 16 kg of CO₂ — more than 88% of aluminum grades. Typical recycled content is 10%.
Manufacturability7
2A06-O's machinability is fair (45/100, worse than 72% of aluminum grades); weldability poor (20/100); formability very good (75/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 2A06-O
Is 2A06 easy to machine?
Machines well in T4/T351 with sharp, high-rake tooling, high surface speed and emulsion flood coolant for a clean finish. Annealed (O) stock is gummy and builds up on the cutting edge, so finish machine after ageing.
Can 2A06 be welded?
Fusion welding (TIG/MIG) is prone to hot cracking and joint softening; production joints are riveted, adhesive-bonded and riveted, or resistance spot welded. Friction stir welding is feasible.
Can 2A06 be formed, bent or molded?
Formability is best in the O temper or in freshly quenched T4 (within a few hours of quench). Deep bends should be made after annealing, then re-solution treated and aged to T62; T6 material is essentially not cold formable.
What surface finishes work on 2A06?
Use Alclad sheet with chromic or boric-sulfuric anodize, or a chemical conversion coating followed by primer. The high copper content darkens decorative anodic films; hard anodize can be applied where wear resistance is needed.
2A06 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Cu | 3.8 – 4.3 | 4.05 |
| Mg | 1.7 – 2.3 | 2 |
| Mn | 0.5 – 1 | 0.7 |
| Tigrain refinement | 0.03 – 0.15 | 0.08 |
| Siimpurity | ≤ 0.5 | — |
| Feimpurity | ≤ 0.5 | — |
| Znimpurity | ≤ 0.1 | — |
| Niimpurity | ≤ 0.1 | — |
| Others (each)others each ≤0.05, total ≤0.10 | ≤ 0.05 | — |
| Al | balance | — |
2A06-O — frequently asked
What is 2A06-O used for?
2A06-O is typically used for aircraft structural sheet and plate, load-bearing airframe frames, fuselage skins and stringers, riveted structural fittings, high-strength machined brackets and bulkheads and rib webs. In short: 2024-class airframe alloy; high strength, riveted joints; low corrosion resistance.
What is the yield strength of 2A06-O?
2A06-O has a typical yield strength of 110 MPa (16 ksi) and a tensile strength of 220 MPa (31.9 ksi) — weaker than 81% of aluminum grades. Strength varies by condition: see the 5 listed tempers.
Is 2A06-O easy to machine?
Reasonably — machinability is rated fair (45/100, worse than 72% of aluminum grades). Machines well in T4/T351 with sharp, high-rake tooling, high surface speed and emulsion flood coolant for a clean finish. Annealed (O) stock is gummy and builds up on the cutting edge, so finish machine after ageing.
Can 2A06-O be welded?
Not readily — weldability is rated poor (20/100). Fusion welding (TIG/MIG) is prone to hot cracking and joint softening; production joints are riveted, adhesive-bonded and riveted, or resistance spot welded. Friction stir welding is feasible.
What surface finishes work on 2A06-O?
Use Alclad sheet with chromic or boric-sulfuric anodize, or a chemical conversion coating followed by primer. The high copper content darkens decorative anodic films; hard anodize can be applied where wear resistance is needed.
Can 2A06-O be formed, bent or molded?
Formability is best in the O temper or in freshly quenched T4 (within a few hours of quench). Deep bends should be made after annealing, then re-solution treated and aged to T62; T6 material is essentially not cold formable.
What is the maximum service temperature of 2A06-O?
2A06-O is rated for continuous use to about 150°C (302 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 2A06-T4 and 2A06-O?
T4 is the default condition — pick the solution treated and naturally aged default for riveted structures and skins, balancing 460 MPa tensile, 12% elongation and fatigue performance. O: choose the annealed condition for deep cold forming and bending or as feedstock before solution treatment and ageing; tensile is only 220 MPa at 18% elongation. Yield strength is 320 MPa in T4 versus 110 MPa in O.
Sources
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- MMPDS-17 (2024/2024-T4, T351 ) — Battelle/FAA (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.