Aluminum 8090-T852
Precip hard
AA 8090 · UNS A98090 · EN AW-8090, AlLi2.5Cu1.5Mg1
T852 = t8 with compressive stress relief
Forging temper where cold work is applied by cold compression; chosen for helicopter frames and fittings needing low residual stress.
Values for the T852 condition
Other 8090 tempers and conditions
8090 is listed in 13 conditions; see the grade overview at 8090.
Compare all 13 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Softest condition, chosen for severe forming, stretch-forming or intermediate processing before solution treatment and aging. | 140 | 265 | 14 | 65 HB | 26 % IACS |
Solution heat treated and naturally aged | Naturally aged, most formable of the heat-treated conditions; used when parts are shaped then artificially aged. | 200 | 330 | 18 | 88 HB | 19 % IACS |
Solution heat treated, cold worked and naturally aged | Sheet condition with moderate strength and useful ductility for forming operations that are followed by artificial aging to T8. | 225 | 350 | 15 | 95 HB | 20 % IACS |
Solution heat treated and overaged (stabilized) | Overaged condition selected when stress-corrosion and exfoliation resistance outweigh maximum strength. | 350 | 430 | 7 | 120 HB | 25 % IACS |
Solution heat treated and artificially aged | Peak-aged without stretching; used for forgings and shapes where cold work before aging is impractical, but strength and toughness are below T8 tempers. | 370 | 465 | 5 | 128 HB | — |
Solution heat treated, ~1 % cold worked, artificially aged | Standard sheet temper for fuselage and secondary skins where damage tolerance and formability matter more than peak plate strength. | 370 | 455 | 7 | 128 HB | 24 % IACS |
Special underaged/toughness-optimised T8 | Proprietary aging practice trading a little yield strength for markedly better fracture toughness and short-transverse ductility in thick sections. | 390 | 470 | 8 | 130 HB | 24 % IACS |
T852This page T8 with compressive stress relief | Forging temper where cold work is applied by cold compression; chosen for helicopter frames and fittings needing low residual stress. | 400 | 470 | 6 | 132 HB | 23 % IACS |
Solution heat treated, cold worked and artificially aged | Generic peak-strength Al-Li condition: cold work before aging refines the strengthening precipitates, giving the best strength/stiffness combination. | 415 | 480 | 6 | 135 HB | 23 % IACS |
T6, stress relieved by stretching | Peak-aged 8090 Al-Li plate stretched 1.5–3 % after solution treatment for low residual stress; highest strength-to-density of the 8090 tempers but reduced short-transverse toughness and SCC resistance versus T8771. | 415 | 480 | 5 | 145 HB | 18 % IACS |
T851Default T8, stress relieved by stretching | The workhorse plate temper for machined aerospace structure: peak strength with low residual stress so thick plate machines flat without distortion. | 425 | 480 | 6 | 135 HB | 23 % IACS |
Solution treated, stretched, cold worked and artificially aged | Slightly higher-strength plate variant of T851 used where static strength governs and short-transverse ductility is less critical. | 435 | 490 | 5 | 138 HB | 23 % IACS |
T6, stress relieved by stretching, minor straightening | Peak-aged 8090 extrusion/bar temper: T651 practice plus permitted minor straightening after stretching, giving high longitudinal strength with strong directional (texture) anisotropy. | 440 | 495 | 5 | 150 HB | 18 % IACS |
What is 8090-T852?
8090-T852 is 8090 in the T852 condition — forging temper where cold work is applied by cold compression; chosen for helicopter frames and fittings needing low residual stress. 8090-T852 has a yield strength of 400 MPa (58 ksi) and a tensile strength of 470 MPa (68.2 ksi) — stronger than 88% of aluminum grades. Elongation at break is 6% and the elastic modulus is 79 GPa (11.5 Msi). 8090-T852 has a density of 2.54 g/cm³ (0.0918 lb/in³), lighter than 100% of aluminum grades. It melts at 600°C (1,112 °F). T851 is the default condition FabDigit quotes; T852 is available on request or by drawing note.
Advantages
- High strength — 400 MPa (58 ksi), better than 88% of aluminum grades
- Tough — resists crack growth — 33 MPa·√m (30 ksi·√in), better than 87% of aluminum grades
Limitations
- Poor heat conductor — 93 W/m·K (53.7 BTU/hr·ft·°F), worse than 99% of aluminum grades
- Low electrical conductivity — 23 % IACS, worse than 97% of aluminum grades
- High embodied carbon — 14 kg CO₂/kg, worse than 95% of aluminum grades
- Limited service temperature — 120°C (248 °F), worse than 79% of aluminum grades
- Difficult to weld — 25/100, worse than 76% of aluminum grades
8090-T852 properties
Typical room-temperature values for 8090-T852; 21 are specific to this condition. Other listed values are 8090 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
8090-T852 has a density of 2.54 g/cm³ (0.0918 lb/in³), lighter than 100% of aluminum grades. It melts at 600°C (1,112 °F).
Mechanical12
8090-T852 has a yield strength of 400 MPa (58 ksi) and a tensile strength of 470 MPa (68.2 ksi) — stronger than 88% of aluminum grades. Elongation at break is 6% and the elastic modulus is 79 GPa (11.5 Msi).
Thermal6
8090-T852 is rated for continuous service to 120°C (248 °F). It conducts heat at 93 W/m·K (53.7 BTU/hr·ft·°F), worse than 99% of aluminum grades. Thermal expansion is 21.4 µm/m·K (11.9 µin/in·°F).
Electrical3
8090-T852 conducts electricity at 23 % IACS, worse than 97% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (40/100), worse than 75% of aluminum grades.
Sustainability4
Producing a kilogram of 8090-T852 takes about 220 MJ of energy and emits 14 kg of CO₂ — more than 95% of aluminum grades. Typical recycled content is 5%.
Manufacturability7
8090-T852's machinability is good (55/100, worse than 59% of aluminum grades); weldability poor (25/100); formability poor (15/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 8090-T852
Is 8090 easy to machine?
Machines like a hard 2000-series alloy but Zr/Li constituents accelerate tool wear — use sharp carbide/PCD, high speed, generous coolant, and keep fine chips wet since Li-bearing dust is reactive.
Can 8090 be welded?
Fusion welding is problematic (Li oxide film, hydrogen porosity, hot cracking); joints are normally riveted, bonded or friction-stir/electron-beam welded rather than TIG/MIG.
Can 8090 be formed, bent or molded?
Form in O, T3 or T4; T8-type plate has low ductility and pronounced through-thickness anisotropy, so bend radii must be generous and short-transverse loading avoided.
What surface finishes work on 8090?
Chromic or sulfuric anodize plus primer is standard for aerospace corrosion protection; alkaline etch times must be controlled because Li-rich phases dissolve preferentially and can dull the finish.
8090 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 |
|---|---|---|
| Liprincipal density-reducing / δ′ forming element | 2.2 – 2.7 | 2.4 |
| Cu | 1 – 1.6 | 1.3 |
| Mg | 0.6 – 1.3 | 0.9 |
| Zrgrain-structure control | 0.04 – 0.16 | 0.1 |
| Fe | ≤ 0.3 | — |
| Si | ≤ 0.2 | — |
| Mn | ≤ 0.1 | — |
| Cr | ≤ 0.1 | — |
| Zn | ≤ 0.25 | — |
| Ti | ≤ 0.1 | — |
| Others (each)total 0.15 max | ≤ 0.05 | — |
| Al | balance | — |
8090-T852 — frequently asked
What is 8090-T852 used for?
8090-T852 is typically used for aerospace structural components, helicopter airframe parts, fuselage frames and bulkheads, wing ribs and stringers, machined structural fittings and seat tracks and floor structure. In short: low-density Al-Li; aerospace classic.
What is the yield strength of 8090-T852?
8090-T852 has a typical yield strength of 400 MPa (58 ksi) and a tensile strength of 470 MPa (68.2 ksi) — stronger than 88% of aluminum grades. Strength varies by condition: see the 13 listed tempers.
Is 8090-T852 easy to machine?
Reasonably — machinability is rated good (55/100, worse than 59% of aluminum grades). Machines like a hard 2000-series alloy but Zr/Li constituents accelerate tool wear — use sharp carbide/PCD, high speed, generous coolant, and keep fine chips wet since Li-bearing dust is reactive.
Can 8090-T852 be welded?
Not readily — weldability is rated poor (25/100). Fusion welding is problematic (Li oxide film, hydrogen porosity, hot cracking); joints are normally riveted, bonded or friction-stir/electron-beam welded rather than TIG/MIG.
What surface finishes work on 8090-T852?
Chromic or sulfuric anodize plus primer is standard for aerospace corrosion protection; alkaline etch times must be controlled because Li-rich phases dissolve preferentially and can dull the finish.
Can 8090-T852 be formed, bent or molded?
Form in O, T3 or T4; T8-type plate has low ductility and pronounced through-thickness anisotropy, so bend radii must be generous and short-transverse loading avoided.
What is the maximum service temperature of 8090-T852?
8090-T852 is rated for continuous use to about 120°C (248 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 8090-T851 and 8090-O?
T851 is the default condition — the workhorse plate temper for machined aerospace structure: peak strength with low residual stress so thick plate machines flat without distortion. O: softest condition, chosen for severe forming, stretch-forming or intermediate processing before solution treatment and aging. Yield strength is 425 MPa in T851 versus 140 MPa in O.
Can FabDigit make parts in 8090-T852?
Yes — 8090-T852 is available for CNC machining and sheet metal; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- International Alloy Designations and Chemical Composition Limits for Wrought Aluminum (Teal Sheets) — The Aluminum Association (2018)
- ASM Specialty Handbook: Aluminum and Aluminum Alloys — ASM International (1993)
- Aluminum-Lithium Alloys: Processing, Properties and Applications — Elsevier/Butterworth-Heinemann (2014)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- Lital A / 8090 plate and sheet property data — British Alcan / Alcan Aerospace (1990)
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.