Aluminum 7079
AA 7079 · UNS A97079
7079 (A97079) is an older high-strength Al-Zn-Mg-Cu alloy developed for thick-section aircraft forgings, supplied in O, W, T6 and the stress-relieved T651, T652, T6510 and T6511 tempers.
Reference datasheet — 7079 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the T6 condition
7079 tempers and conditions
7079 is supplied in 7 conditions, soft to hard. T6 is the default FabDigit quotes; the values on this page are for it.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Softest condition for forming, straightening or re-heat-treating; no service strength. | 110 | 235 | 16 | 62 HB | 45 % IACS |
Solution heat treated (unstable) | Freshly quenched, refrigerated condition used only as a short forming/riveting window before ageing to T6. | 230 | 380 | 17 | 95 HB | 30 % IACS |
T6, stress relieved by compression | Forging temper where residual stress is knocked down by cold compression before ageing — the classic 7079 thick-forging condition. | 448 | 517 | 10 | 140 HB | 33.5 % IACS |
T6, stress relieved by stretching | Thick-plate temper with low residual stress for machined aircraft fittings and bulkheads. | 455 | 524 | 11 | 142 HB | 33.5 % IACS |
Solution treated, stretched, aged; permissible minor straightening | Extruded shapes/bar where tight straightness and low residual stress are needed and minor straightening is allowed. | 460 | 530 | 10 | 143 HB | 33.5 % IACS |
T6, stress relieved by stretching, minor straightening | As T6510 but with the tightest residual-stress control for parts machined to close tolerance from extrusion. | 460 | 530 | 10 | 143 HB | 33.5 % IACS |
T6Default Solution heat treated and artificially aged | Standard peak-aged condition for die forgings and extrusions; highest strength but poorest SCC resistance. | 469 | 538 | 14 | 145 HB | 33.5 % IACS |
What is 7079?
7079 (A97079) is an older high-strength Al-Zn-Mg-Cu alloy developed for thick-section aircraft forgings, supplied in O, W, T6 and the stress-relieved T651, T652, T6510 and T6511 tempers. In T6 it provides about 469 MPa yield, 538 MPa tensile, 14% elongation and 145 HB with 121 W/m·K thermal conductivity, and it machines freely (72/100). Stress-corrosion sensitivity in the short-transverse direction, corrosion resistance of 28/100, no structural arc weldability and a 120 °C service limit restrict its use. The alloy is largely superseded, and 7075 or 7050 is specified for new designs. 7079 has a density of 2.74 g/cm³ (0.099 lb/in³), heavier than 64% of aluminum grades. It melts at 477°C (891 °F). 7079 has a yield strength of 469 MPa (68 ksi) and a tensile strength of 538 MPa (78 ksi) — stronger than 93% of aluminum grades. Elongation at break is 14% and the elastic modulus is 71.7 GPa (10.4 Msi).
What is 7079 used for?
- Legacy aircraft forgings
- Thick-section structural fittings
- Replacement parts for older airframes
- Machined forged brackets and lugs
- Heavy-gauge plate structures
- Hogged-out structural housings
Advantages
- High strength — 469 MPa (68 ksi), better than 93% of aluminum grades
- Ductile — tolerates forming and impact — 14%, better than 81% of aluminum grades
- Easy to machine — 72/100, better than 80% of aluminum grades
- Tough — resists crack growth — 30 MPa·√m (27.3 ksi·√in), better than 76% of aluminum grades
Limitations
- Needs corrosion protection — 28/100, worse than 99% of aluminum grades
- Difficult to weld — 15/100, worse than 96% of aluminum grades
- Limited service temperature — 120°C (248 °F), worse than 79% of aluminum grades
- Poor heat conductor — 121 W/m·K (69.9 BTU/hr·ft·°F), worse than 76% of aluminum grades
7079 properties
Typical room-temperature values for 7079-T6; bars are the position among aluminum grades.
Physical3
7079 has a density of 2.74 g/cm³ (0.099 lb/in³), heavier than 64% of aluminum grades. It melts at 477°C (891 °F).
Mechanical13
7079 has a yield strength of 469 MPa (68 ksi) and a tensile strength of 538 MPa (78 ksi) — stronger than 93% of aluminum grades. Elongation at break is 14% and the elastic modulus is 71.7 GPa (10.4 Msi).
Thermal6
7079 is rated for continuous service to 120°C (248 °F). It conducts heat at 121 W/m·K (69.9 BTU/hr·ft·°F), worse than 76% of aluminum grades. Thermal expansion is 24.3 µm/m·K (13.5 µin/in·°F).
Electrical3
7079 conducts electricity at 33.5 % IACS, worse than 54% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is poor (28/100), worse than 99% of aluminum grades.
Sustainability4
Producing a kilogram of 7079 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
7079's machinability is very good (72/100, better than 80% of aluminum grades); weldability poor (15/100); formability poor (28/100).
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. 7079 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 7079
Is 7079 easy to machine?
Machines like 7075-T6 — free-cutting in the aged condition with sharp carbide tools, high speeds and flood coolant; stress-relieved tempers (T651/T652/T6511) are essential to avoid distortion when hogging thick sections.
Can 7079 be welded?
Not arc weldable for structural use (hot cracking and severe HAZ SCC); join by rivets, bolts or bonding, and repair only by mechanical means.
Can 7079 be formed, bent or molded?
Form in O or freshly quenched W condition then age; cold forming in T6 is limited to large-radius bends because ductility and SCC resistance are low.
7079 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 |
|---|---|---|
| Zn | 3.8 – 4.8 | 4.3 |
| Mg | 2.9 – 3.7 | 3.3 |
| Cu | 0.4 – 0.8 | 0.6 |
| Mn | 0.1 – 0.3 | 0.2 |
| Cr | 0.1 – 0.25 | 0.18 |
| Fe | ≤ 0.4 | |
| Si | ≤ 0.3 | |
| Ti | ≤ 0.1 | |
| Others (each)others total 0.15 max | ≤ 0.05 | |
| Al | balance |
What surface finishes work on 7079?
Responds well to sulfuric and hard anodizing and to chromate/trivalent conversion coating plus epoxy primer — protective coating and avoidance of short-transverse sustained tension are mandatory for corrosion control.
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).
Organic Coating
Equivalent designations
Standards and trade names that resolve to Aluminum 7079 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- A97079
How much does 7079 cost?
7079 is a high-cost aluminum ($$$$), pricier than about 78% 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.
7079 — frequently asked
What is 7079 used for?
7079 is typically used for legacy aircraft forgings, thick-section structural fittings, replacement parts for older airframes, machined forged brackets and lugs, heavy-gauge plate structures and hogged-out structural housings. In short: legacy aerospace forging alloy; superseded by 7075/7050; thick-section high strength.
What is the yield strength of 7079?
7079 has a typical yield strength of 469 MPa (68 ksi) and a tensile strength of 538 MPa (78 ksi) — stronger than 93% of aluminum grades. Strength varies by condition: see the 7 listed tempers.
Is 7079 easy to machine?
Yes — machinability is rated very good (72/100, better than 80% of aluminum grades). Machines like 7075-T6 — free-cutting in the aged condition with sharp carbide tools, high speeds and flood coolant; stress-relieved tempers (T651/T652/T6511) are essential to avoid distortion when hogging thick sections.
Can 7079 be welded?
Not readily — weldability is rated poor (15/100). Not arc weldable for structural use (hot cracking and severe HAZ SCC); join by rivets, bolts or bonding, and repair only by mechanical means.
What surface finishes work on 7079?
Responds well to sulfuric and hard anodizing and to chromate/trivalent conversion coating plus epoxy primer — protective coating and avoidance of short-transverse sustained tension are mandatory for corrosion control.
Can 7079 be formed, bent or molded?
Form in O or freshly quenched W condition then age; cold forming in T6 is limited to large-radius bends because ductility and SCC resistance are low.
What is the maximum service temperature of 7079?
7079 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 7079-T6 and 7079-O?
T6 is the default condition — standard peak-aged condition for die forgings and extrusions; highest strength but poorest SCC resistance. O: softest condition for forming, straightening or re-heat-treating; no service strength. Yield strength is 469 MPa in T6 versus 110 MPa in O.
How much does 7079 cost?
7079 is a high-cost aluminum ($$$$), pricier than about 78% 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.
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 and Special-Purpose Materials — ASM International (1990)
- ASM Handbook Vol. 13B — Corrosion: Materials (Al alloy SCC behavior) — ASM International (2005)
- MMPDS / MIL-HDBK-5 legacy aluminum forging and plate allowables — FAA / Battelle (2003)
- Aluminum Standards and Data (legacy temper listings for 7079) — The Aluminum Association (2013)
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.