Aluminum 7085
AA 7085 · UNS A97085 · EN AW-7085
7085 is a 7000 series Al-Zn-Mg-Cu alloy (UNS A97085, EN AW-7085) developed for thick-section plate and large die forgings, where its low quench sensitivity keeps properties uniform through the cross-section.
Values for the T7451 condition
7085 tempers and conditions
7085 is supplied in 6 conditions, soft to hard. T7451 is the default FabDigit quotes; the values on this page are for it.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution treated, stress-relieved by compression, fully overaged | Forging counterpart of T7351 — maximum SCC/toughness margin in heavy sections at the cost of ~8 % strength. | 421 | 476 | 10 | 136 HB | 43 % IACS |
T73, stress relieved by stretching | Pick when maximum fracture toughness and stress-corrosion resistance dominate over strength — thick plate for damage-tolerant fuselage frames and bulkheads. | 428 | 480 | 12 | 138 HB | 43 % IACS |
Solution treated, stress-relieved by compression, overaged | The standard condition for large 7085 die and hand forgings (bulkheads, landing-gear support ribs) where stress relief is done by cold compression rather than stretching. | 462 | 500 | 9 | 148 HB | 41 % IACS |
T7451Default T74, stress relieved by stretching | Default thick-plate condition: best overall balance of strength, fracture toughness and SCC resistance for machined wing/fuselage structural parts. | 469 | 505 | 11 | 150 HB | 41 % IACS |
T76, stress relieved by stretching | Choose when static strength and exfoliation resistance matter more than maximum toughness — upper wing covers, compression-dominated plate parts. | 496 | 531 | 9 | 158 HB | 39 % IACS |
T76511 | Extrusion condition for 7085 stringers/stiffeners needing high compressive yield plus exfoliation resistance. | 517 | 545 | 9 | 160 HB | 39 % IACS |
What is 7085?
7085 is a 7000 series Al-Zn-Mg-Cu alloy (UNS A97085, EN AW-7085) developed for thick-section plate and large die forgings, where its low quench sensitivity keeps properties uniform through the cross-section. It is supplied as heavy plate and forgings in stress-relieved T7351/T7451/T7651 and T7352/T7452 tempers, with typical values of 469 MPa yield, 505 MPa tensile, 11% elongation and 150 HB. The limits are no fusion weldability, moderate corrosion resistance and a service ceiling near 120 °C. In thinner sections 7050 or 7075 plate is the usual lower-cost alternative. 7085 has a density of 2.85 g/cm³ (0.103 lb/in³), heavier than 96% of aluminum grades. It melts at 477°C (891 °F). 7085 has a yield strength of 469 MPa (68 ksi) and a tensile strength of 505 MPa (73.2 ksi) — stronger than 93% of aluminum grades. Elongation at break is 11% and the elastic modulus is 70.5 GPa (10.2 Msi).
What is 7085 used for?
- Aerospace heavy forgings
- Wing spars
- Fuselage and wing bulkheads
- Machined wing ribs and frames
- Landing gear structural fittings
- Thick-plate airframe fittings
- Large monolithic machined structures
Advantages
- Tough — resists crack growth — 38 MPa·√m (34.6 ksi·√in), better than 96% of aluminum grades
- High strength — 469 MPa (68 ksi), better than 93% of aluminum grades
- High electrical conductivity — 41 % IACS, better than 78% of aluminum grades
Limitations
- Difficult to weld — 20/100, worse than 89% of aluminum grades
- Limited service temperature — 120°C (248 °F), worse than 79% of aluminum grades
7085 properties
Typical room-temperature values for 7085-T7451; bars are the position among aluminum grades.
Physical3
7085 has a density of 2.85 g/cm³ (0.103 lb/in³), heavier than 96% of aluminum grades. It melts at 477°C (891 °F).
Mechanical13
7085 has a yield strength of 469 MPa (68 ksi) and a tensile strength of 505 MPa (73.2 ksi) — stronger than 93% of aluminum grades. Elongation at break is 11% and the elastic modulus is 70.5 GPa (10.2 Msi).
Thermal6
7085 is rated for continuous service to 120°C (248 °F). It conducts heat at 152 W/m·K (87.8 BTU/hr·ft·°F), better than 66% of aluminum grades. Thermal expansion is 23.4 µm/m·K (13 µin/in·°F).
Electrical3
7085 conducts electricity at 41 % IACS, better than 78% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (50/100), worse than 56% of aluminum grades.
Sustainability4
Producing a kilogram of 7085 takes about 205 MJ of energy and emits 12.5 kg of CO₂ — more than 76% of aluminum grades. Typical recycled content is 8%.
Manufacturability8
7085's machinability is very good (70/100, better than 72% of aluminum grades); weldability poor (20/100); formability poor (25/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the aluminum family
Yield strength against density for every aluminum grade FabDigit runs. 7085 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 7085
Is 7085 easy to machine?
Machines very freely in T74/T76 tempers with sharp polished carbide, high speed and flood coolant; large stock removal from thick plate needs symmetric passes and stress-relieved (T7x51/T7x52) material to control distortion.
Can 7085 be welded?
Not fusion weldable (hot cracking, drastic HAZ property loss) — join by riveting, bolting or friction stir welding with post-weld property allowance.
Can 7085 be formed, bent or molded?
Formed hot as thick plate or die forging; in the aged temper only mild bending/straightening is possible — do stretch/compression stress relief before machining.
Manufacturability
The process limits FabDigit applies to 7085. Every 7085 part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
CNC machining
| Machinability | Excellent70 / 100 |
|---|---|
| ISO material group | N.1 |
| Cutting speed (rough / finish) | 350 / 420 m/min |
| Minimum wall | 0.5 mm |
| Minimum internal radius | 1 mm |
| Drill depth limit | 8× diameter |
| Best surface (machined / polished) | Ra 0.8 / — |
| Hardenable after machining | No |
Sheet metal
| Formability | Not Recommend25 / 100 |
|---|---|
| Weldability | Not Recommend20 / 100 |
7085 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 |
|---|---|---|
| Si | ≤ 0.06 | 0.03 |
| Femax — kept very low for toughness | ≤ 0.08 | 0.05 |
| Cu | 1.3 – 2 | 1.6 |
| Mn | ≤ 0.04 | 0.01 |
| Mg | 1.2 – 1.8 | 1.5 |
| Cr | ≤ 0.04 | 0.01 |
| Zn | 7 – 8 | 7.5 |
| Ti | ≤ 0.06 | 0.03 |
| Zrdispersoid former, replaces Cr/Mn | 0.08 – 0.15 | 0.11 |
| Others (each) | ≤ 0.05 | |
| Others (total) | ≤ 0.15 | |
| Al | balance |
What surface finishes work on 7085?
Chromic or boric-sulfuric anodize plus epoxy primer for aerospace corrosion protection; hard anodize possible but grey-tinted, and shot peening or Alclad/paint systems are used on exposed surfaces.
Surface treatments FabDigit runs on aluminum parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Passivation
Conversion Coating
PVD Coating
Equivalent designations
Standards and trade names that resolve to Aluminum 7085 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- A97085
- Aluminum Association
- AA7085
- EN / DIN / Werkstoff-Nr.
- AW-7085
How much does 7085 cost?
7085 is a high-cost aluminum ($$$$), pricier than about 98% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
7085 — frequently asked
What is 7085 used for?
7085 is typically used for aerospace heavy forgings, wing spars, fuselage and wing bulkheads, machined wing ribs and frames, landing gear structural fittings and thick-plate airframe fittings. In short: ultra-thick aerospace forging; low quench sensitivity.
What is the yield strength of 7085?
7085 has a typical yield strength of 469 MPa (68 ksi) and a tensile strength of 505 MPa (73.2 ksi) — stronger than 93% of aluminum grades. Strength varies by condition: see the 6 listed tempers.
Is 7085 easy to machine?
Yes — machinability is rated very good (70/100, better than 72% of aluminum grades). Machines very freely in T74/T76 tempers with sharp polished carbide, high speed and flood coolant; large stock removal from thick plate needs symmetric passes and stress-relieved (T7x51/T7x52) material to control distortion.
Can 7085 be welded?
Not readily — weldability is rated poor (20/100). Not fusion weldable (hot cracking, drastic HAZ property loss) — join by riveting, bolting or friction stir welding with post-weld property allowance.
What surface finishes work on 7085?
Chromic or boric-sulfuric anodize plus epoxy primer for aerospace corrosion protection; hard anodize possible but grey-tinted, and shot peening or Alclad/paint systems are used on exposed surfaces.
Can 7085 be formed, bent or molded?
Formed hot as thick plate or die forging; in the aged temper only mild bending/straightening is possible — do stretch/compression stress relief before machining.
What is the maximum service temperature of 7085?
7085 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 7085-T7451 and 7085-T7352?
T7451 is the default condition — default thick-plate condition: best overall balance of strength, fracture toughness and SCC resistance for machined wing/fuselage structural parts. T7352: forging counterpart of T7351 — maximum SCC/toughness margin in heavy sections at the cost of ~8 % strength. Yield strength is 469 MPa in T7451 versus 421 MPa in T7352.
How much does 7085 cost?
7085 is a high-cost aluminum ($$$$), pricier than about 98% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Can FabDigit make parts in 7085?
Yes — 7085 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)
- AMS 4413 / AMS 4414 — Aluminum Alloy 7085 Plate and Die Forgings — SAE International (2016)
- Alcoa 7085 thick plate and forgings product information — Alcoa / Arconic (2010)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- MMPDS-17 Metallic Materials Properties Development and Standardization — Battelle / FAA (2022)
- ASM Handbook Vol. 13B — Corrosion: Materials — ASM International (2005)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.