Aluminum 2094-T81
Temper
AA 2094 · UNS A92094
T81 = solution heat treated, ~1 % cold worked and artificially aged
Lightly stretched sheet temper balancing strength with somewhat better ductility than T861.
Values for the T81 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 |
|---|---|---|---|---|---|---|
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 |
T81This page 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-T81?
2094-T81 is 2094 in the T81 temper — lightly stretched sheet temper balancing strength with somewhat better ductility than T861. 2094-T81 has a yield strength of 555 MPa (80.5 ksi) and a tensile strength of 600 MPa (87 ksi) — stronger than 98% of aluminum grades. Elongation at break is 7% and the elastic modulus is 78 GPa (11.3 Msi). 2094-T81 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; T81 is available on request or by drawing note.
Advantages
- High strength — 555 MPa (80.5 ksi), better than 98% of aluminum grades
- Tough — resists crack growth — 32 MPa·√m (29.1 ksi·√in), better than 83% of aluminum grades
Limitations
- Low electrical conductivity — 20 % IACS, worse than 99% of aluminum grades
- Poor heat conductor — 95 W/m·K (54.9 BTU/hr·ft·°F), worse than 98% of aluminum grades
- Needs corrosion protection — 40/100, worse than 75% of aluminum grades
2094-T81 properties
Typical room-temperature values for 2094-T81; 21 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-T81 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-T81 has a yield strength of 555 MPa (80.5 ksi) and a tensile strength of 600 MPa (87 ksi) — stronger than 98% of aluminum grades. Elongation at break is 7% and the elastic modulus is 78 GPa (11.3 Msi).
Thermal6
2094-T81 is rated for continuous service to 150°C (302 °F). It conducts heat at 95 W/m·K (54.9 BTU/hr·ft·°F), worse than 98% of aluminum grades. Thermal expansion is 21.8 µm/m·K (12.1 µin/in·°F).
Electrical3
2094-T81 conducts electricity at 20 % IACS, worse than 99% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (40/100), worse than 75% of aluminum grades.
Sustainability4
Producing a kilogram of 2094-T81 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-T81's machinability is good (62/100, better than 55% of aluminum grades); weldability good (55/100); formability poor (33/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 2094-T81
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-T81 — frequently asked
What is 2094-T81 used for?
2094-T81 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-T81?
2094-T81 has a typical yield strength of 555 MPa (80.5 ksi) and a tensile strength of 600 MPa (87 ksi) — stronger than 98% of aluminum grades. Strength varies by condition: see the 9 listed tempers.
Is 2094-T81 easy to machine?
Reasonably — machinability is rated good (62/100, better than 55% 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-T81 be welded?
Yes — weldability is rated good (55/100). 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-T81?
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-T81 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-T81?
2094-T81 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.