Aluminum 2094-O (Annealed)
Temper
AA 2094 · UNS A92094
Softest condition for forming, straightening or intermediate processing before re-solution treatment.
Values for the O condition
Other 2094 tempers and conditions
2094 is listed in 9 conditions; see the grade overview at 2094.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
OThis page Annealed | Softest condition for forming, straightening or intermediate processing before re-solution treatment. | 135 | 250 | 16 | 65 HB | 28 % IACS |
Solution heat treated and naturally aged | Un-stretched naturally aged stock for forming operations followed by artificial ageing. | 260 | 415 | 17 | 115 HB | 18 % IACS |
Solution heat treated, cold worked and naturally aged | Intermediate strength with better ductility; used as a forming/pre-age condition before final T8 ageing. | 310 | 460 | 14 | 125 HB | 18 % IACS |
Solution heat treated and artificially aged | Aged without stretching — used for forgings/parts that cannot be stretched; lower strength than T8 tempers. | 505 | 565 | 6 | 158 HB | 20 % IACS |
Solution heat treated, ~1 % cold worked and artificially aged | Lightly stretched sheet temper balancing strength with somewhat better ductility than T861. | 555 | 600 | 7 | 165 HB | 20 % IACS |
Solution heat treated, cold worked and artificially aged | Generic stretched-and-aged high-strength condition for sheet and extrusions. | 570 | 610 | 6 | 168 HB | 20 % IACS |
T8, stress relieved by stretching | Standard stress-relieved plate temper for machined aerospace structure with stable dimensions. | 575 | 615 | 6 | 170 HB | 20 % IACS |
T8 with 7 % cold work | Heavily stretched, artificially aged temper used for cryogenic tank plate where strength and weld-repair stability matter. | 585 | 620 | 6 | 172 HB | 20 % IACS |
T861Default Solution heat treated, ~6 % cold worked and artificially aged | Peak-strength Weldalite condition — the usual stocked temper for 2094 sheet, plate and extrusions. | 600 | 635 | 5 | 175 HB | 20 % IACS |
What is 2094-O?
2094-O is 2094 in the O temper — softest condition for forming, straightening or intermediate processing before re-solution treatment. 2094-O has a yield strength of 135 MPa (19.6 ksi) and a tensile strength of 250 MPa (36.3 ksi) — weaker than 72% of aluminum grades. Elongation at break is 16% and the elastic modulus is 77 GPa (11.2 Msi). 2094-O has a density of 2.6 g/cm³ (0.0939 lb/in³), lighter than 97% of aluminum grades. It melts at 530°C (986 °F). T861 is the default condition FabDigit quotes; O is available on request or by drawing note.
Advantages
- Tough — resists crack growth — 45 MPa·√m (41 ksi·√in), better than 100% of aluminum grades
- Ductile — tolerates forming and impact — 16%, better than 84% of aluminum grades
- Forms and bends easily — 65/100, better than 80% of aluminum grades
Limitations
- Low electrical conductivity — 28 % IACS, worse than 82% of aluminum grades
2094-O properties
Typical room-temperature values for 2094-O; 22 are specific to this condition. Other listed values are 2094 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
2094-O has a density of 2.6 g/cm³ (0.0939 lb/in³), lighter than 97% of aluminum grades. It melts at 530°C (986 °F).
Mechanical12
2094-O has a yield strength of 135 MPa (19.6 ksi) and a tensile strength of 250 MPa (36.3 ksi) — weaker than 72% of aluminum grades. Elongation at break is 16% and the elastic modulus is 77 GPa (11.2 Msi).
Thermal6
2094-O is rated for continuous service to 150°C (302 °F). It conducts heat at 125 W/m·K (72.2 BTU/hr·ft·°F), worse than 72% of aluminum grades. Thermal expansion is 21.8 µm/m·K (12.1 µin/in·°F).
Electrical3
2094-O conducts electricity at 28 % IACS, worse than 82% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (45/100), worse than 62% of aluminum grades.
Sustainability4
Producing a kilogram of 2094-O takes about 215 MJ of energy and emits 13 kg of CO₂ — more than 93% of aluminum grades. Typical recycled content is 5%.
Manufacturability7
2094-O's machinability is fair (45/100, worse than 72% of aluminum grades); weldability good (60/100); formability good (65/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 2094-O
Is 2094 easy to machine?
Machines like aged 2000 series but abrasive Li/Zr phases favour sharp carbide or PCD tooling, high speed and flood coolant; keep chips dry and segregated because fine Al-Li swarf is reactive.
Can 2094 be welded?
Developed for weldability — FSW is preferred and GTAW/GMAW with 2319 or matching Al-Cu-Li filler is feasible, but the HAZ loses ageing response and post-weld ageing or local re-heat-treat is normally required.
Can 2094 be formed, bent or molded?
Form in O/T3/T4 tempers before final ageing; peak-aged T8x tempers have low ductility, strong texture-driven anisotropy and limited bend capability.
What surface finishes work on 2094?
Use chromate or boric-sulfuric/chromic anodize plus primer for protection; bare surfaces pit in chlorides, and the Cu/Li content gives dark, uneven decorative anodic films.
2094 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 |
|---|---|---|
| Siimpurity limit | ≤ 0.12 | — |
| Feimpurity limit | ≤ 0.15 | — |
| Cu | 4.4 – 5.2 | 4.8 |
| Mn | ≤ 0.25 | — |
| Mg | 0.25 – 0.8 | 0.4 |
| Zn | ≤ 0.25 | — |
| Ti | ≤ 0.1 | — |
| Agpromotes fine T1 precipitation | 0.25 – 0.6 | 0.4 |
| Lidensity reduction, stiffness increase | 0.8 – 1.5 | 1.1 |
| Zrgrain-structure control | 0.04 – 0.18 | 0.11 |
| Others (each) | ≤ 0.05 | — |
| Others (total) | ≤ 0.15 | — |
| Al | balance | — |
2094-O — frequently asked
What is 2094-O used for?
2094-O is typically used for fuselage plate, wing skin plate, machined integrally stiffened panels, launch vehicle and cryogenic tank sections, high-strength airframe fittings and friction-stir-welded structural assemblies. In short: highest-strength Al-Li plate; weldable by FSW; low ductility when peak-aged.
What is the yield strength of 2094-O?
2094-O has a typical yield strength of 135 MPa (19.6 ksi) and a tensile strength of 250 MPa (36.3 ksi) — weaker than 72% of aluminum grades. Strength varies by condition: see the 9 listed tempers.
Is 2094-O easy to machine?
Reasonably — machinability is rated fair (45/100, worse than 72% of aluminum grades). Machines like aged 2000 series but abrasive Li/Zr phases favour sharp carbide or PCD tooling, high speed and flood coolant; keep chips dry and segregated because fine Al-Li swarf is reactive.
Can 2094-O be welded?
Yes — weldability is rated good (60/100). Developed for weldability — FSW is preferred and GTAW/GMAW with 2319 or matching Al-Cu-Li filler is feasible, but the HAZ loses ageing response and post-weld ageing or local re-heat-treat is normally required.
What surface finishes work on 2094-O?
Use chromate or boric-sulfuric/chromic anodize plus primer for protection; bare surfaces pit in chlorides, and the Cu/Li content gives dark, uneven decorative anodic films.
Can 2094-O be formed, bent or molded?
Form in O/T3/T4 tempers before final ageing; peak-aged T8x tempers have low ductility, strong texture-driven anisotropy and limited bend capability.
What is the maximum service temperature of 2094-O?
2094-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 2094-T861 and 2094-O?
T861 is the default condition — peak-strength Weldalite condition — the usual stocked temper for 2094 sheet, plate and extrusions. O: softest condition for forming, straightening or intermediate processing before re-solution treatment. Yield strength is 600 MPa in T861 versus 135 MPa in O.
Sources
- International Alloy Designations and Chemical Composition Limits for Wrought Aluminum (Teal Sheets) — The Aluminum Association (2018)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys (Aluminum-Lithium Alloys) — ASM International (1990)
- Aluminum-Lithium Alloys: Processing, Properties and Applications — Butterworth-Heinemann/Elsevier (2014)
- Weldalite 049 / 2094-2095 alloy technical data — Reynolds Metals / Lockheed Martin (1994)
- MMPDS-style typical property compilations for Al-Li aerospace alloys — Battelle (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.