Aluminum 7049-T76
Precip hard
AA 7049 · UNS A97049 · EN AW-7049, AW 7049
T76 = overaged for exfoliation-corrosion resistance
Intermediate overage: higher strength than T73 with good exfoliation-corrosion resistance but less SCC margin.
Values for the T76 condition
Other 7049 tempers and conditions
7049 is listed in 5 conditions; see the grade overview at 7049.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
T73, stress relieved by stretching | Plate temper for machined structural parts where low residual stress and dimensional stability after heavy metal removal are required. | 455 | 525 | 11 | 130 HB | 40 % IACS |
Overaged, stress-relieved by compression | Hand and die forgings that will be extensively machined; compression stress relief minimises distortion. | 460 | 530 | 10 | 132 HB | 40 % IACS |
Solution heat treated and overaged for stress-corrosion resistance | Standard condition for 7049 die forgings and bar: ~10 % below peak strength but very high resistance to stress-corrosion cracking. | 475 | 545 | 11 | 135 HB | 40 % IACS |
T74-type overage, stress-relieved by compression | Preferred temper for thick 7049 landing-gear forgings: strength between T76 and T73 with near-T73 SCC resistance and good short-transverse properties. | 485 | 550 | 10 | 137 HB | 39 % IACS |
T76This page Overaged for exfoliation-corrosion resistance | Intermediate overage: higher strength than T73 with good exfoliation-corrosion resistance but less SCC margin. | 505 | 565 | 10 | 140 HB | 38 % IACS |
What is 7049-T76?
7049-T76 is 7049 in the T76 condition — intermediate overage: higher strength than T73 with good exfoliation-corrosion resistance but less SCC margin. 7049-T76 has a yield strength of 505 MPa (73.2 ksi) and a tensile strength of 565 MPa (81.9 ksi) — stronger than 96% of aluminum grades. Elongation at break is 10% and the elastic modulus is 71.7 GPa (10.4 Msi). 7049-T76 has a density of 2.84 g/cm³ (0.103 lb/in³), heavier than 93% of aluminum grades. It melts at 477°C (891 °F).
Advantages
- High strength — 505 MPa (73.2 ksi), better than 96% of aluminum grades
- Easy to machine — 72/100, better than 80% of aluminum grades
Limitations
- Difficult to weld — 15/100, worse than 96% of aluminum grades
7049-T76 properties
Typical room-temperature values for 7049-T76; 21 are specific to this condition. Other listed values are 7049 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
7049-T76 has a density of 2.84 g/cm³ (0.103 lb/in³), heavier than 93% of aluminum grades. It melts at 477°C (891 °F).
Mechanical14
7049-T76 has a yield strength of 505 MPa (73.2 ksi) and a tensile strength of 565 MPa (81.9 ksi) — stronger than 96% of aluminum grades. Elongation at break is 10% and the elastic modulus is 71.7 GPa (10.4 Msi).
Thermal6
7049-T76 is rated for continuous service to 150°C (302 °F). It conducts heat at 147 W/m·K (84.9 BTU/hr·ft·°F), better than 55% of aluminum grades. Thermal expansion is 23.4 µm/m·K (13 µin/in·°F).
Electrical3
7049-T76 conducts electricity at 38 % IACS, better than 61% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (43/100), worse than 65% of aluminum grades.
Sustainability4
Producing a kilogram of 7049-T76 takes about 215 MJ of energy and emits 13.5 kg of CO₂ — more than 93% of aluminum grades. Typical recycled content is 10%.
Manufacturability8
7049-T76's machinability is very good (72/100, better than 80% of aluminum grades); weldability poor (15/100); formability poor (20/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 7049-T76
Is 7049 easy to machine?
Machines well in the overaged tempers with sharp carbide tools, high speed and flood coolant; chips are tough so use polished flutes and generous rake to avoid built-up edge.
Can 7049 be welded?
Not weldable by fusion processes (hot cracking and loss of SCC resistance); join by fasteners, adhesive bonding or friction stir with qualified procedures.
Can 7049 be formed, bent or molded?
Hot-work / forge at about 350–440 °C; cold forming in T73-type tempers is very limited — form in the solution-treated (W) state or before ageing.
What surface finishes work on 7049?
Chromic or sulfuric anodize plus primer for aerospace corrosion protection; keep parts insulated from steel and carbon composites, and shot-peen critical machined surfaces for fatigue life.
7049 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 | 7.2 – 8.2 | 7.7 |
| Mg | 2 – 2.9 | 2.45 |
| Cu | 1.2 – 1.9 | 1.55 |
| Crgrain-boundary/quench-sensitivity control | 0.1 – 0.22 | 0.16 |
| Fe | ≤ 0.35 | — |
| Si | ≤ 0.25 | — |
| Mn | ≤ 0.2 | — |
| Ti | ≤ 0.1 | — |
| Others (each)0.15 total | ≤ 0.05 | — |
| Al | balance | — |
7049-T76 — frequently asked
What is 7049-T76 used for?
7049-T76 is typically used for aircraft landing gear forgings, airframe fittings and lugs, support arms and links, thick-section closed-die forgings, hand (open-die) forgings and thick plate for machined structural parts. In short: high-strength aerospace forging.
What is the yield strength of 7049-T76?
7049-T76 has a typical yield strength of 505 MPa (73.2 ksi) and a tensile strength of 565 MPa (81.9 ksi) — stronger than 96% of aluminum grades. Strength varies by condition: see the 5 listed tempers.
Is 7049-T76 easy to machine?
Yes — machinability is rated very good (72/100, better than 80% of aluminum grades). Machines well in the overaged tempers with sharp carbide tools, high speed and flood coolant; chips are tough so use polished flutes and generous rake to avoid built-up edge.
Can 7049-T76 be welded?
Not readily — weldability is rated poor (15/100). Not weldable by fusion processes (hot cracking and loss of SCC resistance); join by fasteners, adhesive bonding or friction stir with qualified procedures.
What surface finishes work on 7049-T76?
Chromic or sulfuric anodize plus primer for aerospace corrosion protection; keep parts insulated from steel and carbon composites, and shot-peen critical machined surfaces for fatigue life.
Can 7049-T76 be formed, bent or molded?
Hot-work / forge at about 350–440 °C; cold forming in T73-type tempers is very limited — form in the solution-treated (W) state or before ageing.
What is the maximum service temperature of 7049-T76?
7049-T76 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.
Can FabDigit make parts in 7049-T76?
Yes — 7049-T76 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 Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
- ASM Handbook Vol. 19 — Fatigue and Fracture — ASM International (1996)
- MMPDS — Metallic Materials Properties Development and Standardization — FAA/Battelle (2023)
- AMS 4111 / AMS-QQ-A-367 aluminium forging specifications — SAE International (2019)
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.