Aluminum 2A16-O (Annealed)
Temper
GB 2A16
Softest condition for cold forming, deep drawing and machining before heat treatment.
Values for the O condition
Other 2A16 tempers and conditions
2A16 is listed in 6 conditions; see the grade overview at 2A16.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
OThis page Annealed | Softest condition for cold forming, deep drawing and machining before heat treatment. | 80 | 185 | 20 | 48 HB | 44 % IACS |
As fabricated | Mill stock intended for subsequent forging and full solution + ageing treatment; properties not guaranteed. | 140 | 250 | 14 | 70 HB | 40 % IACS |
Solution heat treated and naturally aged | Pick when parts must be formed or riveted after solution treatment and only moderate strength is needed. | 185 | 340 | 16 | 90 HB | 28 % IACS |
T6, heat treated by the user | Used for parts formed or welded in the soft state and then given a full heat treatment cycle. | 260 | 395 | 10 | 108 HB | 30 % IACS |
T6Default Solution heat treated and artificially aged | Standard supply condition: peak strength plus the best retention of strength at 200–250 °C. | 265 | 400 | 10 | 110 HB | 30 % IACS |
T8, stress relieved by stretching | Choose for thick plate and machined structural parts where low residual stress and higher yield strength matter. | 320 | 425 | 8 | 120 HB | 32 % IACS |
What is 2A16-O?
2A16-O is 2A16 in the O temper — softest condition for cold forming, deep drawing and machining before heat treatment. 2A16-O has a yield strength of 80 MPa (11.6 ksi) and a tensile strength of 185 MPa (26.8 ksi) — weaker than 90% of aluminum grades. Elongation at break is 20% and the elastic modulus is 72 GPa (10.4 Msi). 2A16-O has a density of 2.84 g/cm³ (0.103 lb/in³), heavier than 93% of aluminum grades. It melts at 540°C (1,004 °F). T6 is the default condition FabDigit quotes; O is available on request or by drawing note.
Advantages
- High service temperature — 200°C (392 °F), better than 90% of aluminum grades
- Ductile — tolerates forming and impact — 20%, better than 89% of aluminum grades
- High electrical conductivity — 44 % IACS, better than 85% of aluminum grades
- Forms and bends easily — 70/100, better than 83% of aluminum grades
- Conducts heat well — 170 W/m·K (98.2 BTU/hr·ft·°F), better than 82% of aluminum grades
Limitations
- Needs corrosion protection — 33/100, worse than 91% of aluminum grades
- Low strength — 80 MPa (11.6 ksi), worse than 90% of aluminum grades
2A16-O properties
Typical room-temperature values for 2A16-O; 10 are specific to this condition. Other listed values are 2A16 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
2A16-O has a density of 2.84 g/cm³ (0.103 lb/in³), heavier than 93% of aluminum grades. It melts at 540°C (1,004 °F).
Mechanical13
2A16-O has a yield strength of 80 MPa (11.6 ksi) and a tensile strength of 185 MPa (26.8 ksi) — weaker than 90% of aluminum grades. Elongation at break is 20% and the elastic modulus is 72 GPa (10.4 Msi).
Thermal6
2A16-O is rated for continuous service to 200°C (392 °F). It conducts heat at 170 W/m·K (98.2 BTU/hr·ft·°F), better than 82% of aluminum grades. Thermal expansion is 22.6 µm/m·K (12.6 µin/in·°F).
Electrical3
2A16-O conducts electricity at 44 % IACS, better than 85% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is poor (33/100), worse than 91% of aluminum grades.
Sustainability4
Producing a kilogram of 2A16-O takes about 210 MJ of energy and emits 12.5 kg of CO₂ — more than 88% of aluminum grades. Typical recycled content is 8%.
Manufacturability7
2A16-O's machinability is fair (45/100, worse than 72% of aluminum grades); weldability very good (72/100); formability very good (70/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 2A16-O
Is 2A16 easy to machine?
Machines cleanly in T6/T851 with sharp carbide tools, high speed and flood coolant; gummy and prone to built-up edge in the O temper.
Can 2A16 be welded?
One of the better-welding 2000-series alloys — TIG/MIG or FSW with ER2319-type filler; expect ~60 % joint efficiency as-welded unless re-solution treated and aged.
Can 2A16 be formed, bent or molded?
Form in O or freshly quenched T4 condition; T6/T851 stock has limited bend ductility (min bend radius ≥3–4 t) and should be hot formed at 300–400 °C if severe.
What surface finishes work on 2A16?
Chromic or sulfuric anodize plus primer/paint, or alclad sheet, is normally specified; conversion coating (chromate/Cr-free) before painting is standard because bare surfaces pit readily.
2A16 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 |
|---|---|---|
| Cumain strengthening element (Al₂Cu) | 6 – 7 | 6.5 |
| Mngrain/recrystallisation control, heat resistance | 0.4 – 0.8 | 0.6 |
| Tigrain refinement, weld cracking resistance | 0.1 – 0.2 | 0.15 |
| Siimpurity limit | ≤ 0.3 | — |
| Feimpurity limit | ≤ 0.3 | — |
| Mgkept low (2A17 is the Mg-bearing variant) | ≤ 0.05 | — |
| Znimpurity limit | ≤ 0.1 | — |
| Niimpurity limit | ≤ 0.1 | — |
| Other (each)others total ≤0.15 | ≤ 0.05 | — |
| Al | balance | — |
2A16-O — frequently asked
What is 2A16-O used for?
2A16-O is typically used for elevated-temperature structural parts, engine nacelle components, welded structural assemblies above 150 °C, heat-resistant sheet and plate skins, forged high-temperature fittings and machined brackets near hot zones. In short: most weldable 2000-series grade; 250 °C service capability; 2219-class heat resistance.
What is the yield strength of 2A16-O?
2A16-O has a typical yield strength of 80 MPa (11.6 ksi) and a tensile strength of 185 MPa (26.8 ksi) — weaker than 90% of aluminum grades. Strength varies by condition: see the 6 listed tempers.
Is 2A16-O easy to machine?
Reasonably — machinability is rated fair (45/100, worse than 72% of aluminum grades). Machines cleanly in T6/T851 with sharp carbide tools, high speed and flood coolant; gummy and prone to built-up edge in the O temper.
Can 2A16-O be welded?
Yes — weldability is rated very good (72/100). One of the better-welding 2000-series alloys — TIG/MIG or FSW with ER2319-type filler; expect ~60 % joint efficiency as-welded unless re-solution treated and aged.
What surface finishes work on 2A16-O?
Chromic or sulfuric anodize plus primer/paint, or alclad sheet, is normally specified; conversion coating (chromate/Cr-free) before painting is standard because bare surfaces pit readily.
Can 2A16-O be formed, bent or molded?
Form in O or freshly quenched T4 condition; T6/T851 stock has limited bend ductility (min bend radius ≥3–4 t) and should be hot formed at 300–400 °C if severe.
What is the maximum service temperature of 2A16-O?
2A16-O is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 2A16-T6 and 2A16-O?
T6 is the default condition — standard supply condition: peak strength plus the best retention of strength at 200–250 °C. O: softest condition for cold forming, deep drawing and machining before heat treatment. Yield strength is 265 MPa in T6 versus 80 MPa in O.
Sources
- ASM Handbook Vol.2: Properties and Selection — Nonferrous Alloys (2219 data used as analogue) — ASM International (1990)
- MMPDS-17 aluminium 2219 property tables (analogue) — 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.