Aluminum 7449
AA 7449 · UNS A97449 · EN AW-7449
7449 is a European high-strength Al-Zn-Mg-Cu plate and forging alloy (A97449, EN AW-7449) developed by Alcan/Constellium, offered in O, T6/T651 and the over-aged T7651, T76511, T7951, T79511 and T7452 tempers.
Reference datasheet — 7449 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 T7951 condition
7449 tempers and conditions
7449 is supplied in 8 conditions, soft to hard. T7951 is the default FabDigit quotes; the values on this page are for it.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Mill/intermediate condition for heavy forming or re-heat-treat; not a service temper. | 110 | 235 | 16 | 65 HB | 45 % IACS |
Forging, solution treated, cold-compression stress relieved, overaged | Die/hand forgings where through-thickness SCC resistance and low residual stress matter. | 545 | 590 | 8 | 172 HB | 39 % IACS |
T7951Default Solution treated, stretched, retrogression/near-peak overaged plate | The standard supply condition for 7449 thick plate: near-peak strength with improved SCC/exfoliation over T6. | 570 | 620 | 10 | 180 HB | 38 % IACS |
T76, stress relieved by stretching | Best compromise of high strength with good exfoliation resistance for wing skin plate. | 605 | 640 | 9 | 188 HB | 35 % IACS |
T6, stress relieved by stretching | Peak-aged plate with low residual stress for machined parts where SCC exposure is limited. | 615 | 655 | 8 | 193 HB | 31 % IACS |
Extrusion, solution treated, stretched, T79 overaged | High-strength stringer extrusions for upper wing panels. | 615 | 645 | 9 | 188 HB | 37 % IACS |
Solution heat treated and artificially aged | Maximum strength for thin, non-stress-corrosion-critical parts; poorest SCC/exfoliation resistance. | 620 | 660 | 8 | 195 HB | 31 % IACS |
Extrusion, solution treated, stretched, T76 overaged | Stringer/spar extrusions needing high strength with exfoliation resistance. | 620 | 650 | 9 | 190 HB | 35 % IACS |
What is 7449?
7449 is a European high-strength Al-Zn-Mg-Cu plate and forging alloy (A97449, EN AW-7449) developed by Alcan/Constellium, offered in O, T6/T651 and the over-aged T7651, T76511, T7951, T79511 and T7452 tempers. It is used for thick wing plate and forged wing structure at 570 MPa yield, 620 MPa tensile, 10% elongation and 180 HB, and machines comparatively freely for the class (78/100). Corrosion resistance is moderate (45/100), the alloy is not fusion weldable and service is capped at 120 °C; 7055 and 7150 are the closest equivalents. 7449 has a density of 2.82 g/cm³ (0.102 lb/in³), heavier than 89% of aluminum grades. It melts at 475°C (887 °F). 7449 has a yield strength of 570 MPa (82.7 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 98% of aluminum grades. Elongation at break is 10% and the elastic modulus is 70 GPa (10.2 Msi).
What is 7449 used for?
- Aircraft wing plate
- Forged wing structure
- High-strength structural components
- Machined wing ribs and spars
- Airframe forgings and fittings
- Thick plate for machined aerospace structure
Advantages
- High strength — 570 MPa (82.7 ksi), better than 98% of aluminum grades
- Easy to machine — 78/100, better than 89% of aluminum grades
- Tough — resists crack growth — 30 MPa·√m (27.3 ksi·√in), better than 76% of aluminum grades
Limitations
- Difficult to weld — 18/100, worse than 94% of aluminum grades
- Limited service temperature — 120°C (248 °F), worse than 79% of aluminum grades
7449 properties
Typical room-temperature values for 7449-T7951; bars are the position among aluminum grades.
Physical3
7449 has a density of 2.82 g/cm³ (0.102 lb/in³), heavier than 89% of aluminum grades. It melts at 475°C (887 °F).
Mechanical13
7449 has a yield strength of 570 MPa (82.7 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 98% of aluminum grades. Elongation at break is 10% and the elastic modulus is 70 GPa (10.2 Msi).
Thermal6
7449 is rated for continuous service to 120°C (248 °F). It conducts heat at 154 W/m·K (89 BTU/hr·ft·°F), better than 68% of aluminum grades. Thermal expansion is 23.4 µm/m·K (13 µin/in·°F).
Electrical3
7449 conducts electricity at 38 % IACS, better than 61% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (45/100), worse than 62% of aluminum grades.
Sustainability4
Producing a kilogram of 7449 takes about 205 MJ of energy and emits 12.5 kg of CO₂ — more than 76% of aluminum grades. Typical recycled content is 12%.
Manufacturability7
7449's machinability is very good (78/100, better than 89% of aluminum grades); weldability poor (18/100); formability poor (22/100).
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. 7449 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 7449
Is 7449 easy to machine?
Machines well in T7x with sharp polished-flute carbide tools, high speed and flood or MQL coolant; plan symmetric stock removal and stress-relieved (T-x51/x52) material to control distortion in thin-web parts.
Can 7449 be welded?
Not suitable for fusion welding (hot cracking, severe HAZ softening and SCC); join by fasteners, bonding, or friction stir welding with qualified parameters.
Can 7449 be formed, bent or molded?
Form in W or freshly quenched condition or hot; aged T6/T7x plate has low ductility and large minimum bend radii — cold forming is limited to gentle contours and stretch-forming of skins.
7449 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 | 0.06 |
| Feimpurity limit | ≤ 0.15 | 0.08 |
| Cu | 1.4 – 2.1 | 1.8 |
| Mn | ≤ 0.2 | 0.05 |
| Mg | 1.8 – 2.7 | 2.2 |
| Cr | ≤ 0.05 | 0.02 |
| Znprincipal strengthening addition | 7.5 – 8.7 | 8.1 |
| Tigrain refiner | ≤ 0.25 | 0.03 |
| Zrdispersoid former (reported with Ti as Ti+Zr limit in some registrations) | ≤ 0.25 | 0.12 |
| Others (each) | ≤ 0.05 | |
| Others (total) | ≤ 0.15 | |
| Al | balance |
What surface finishes work on 7449?
Chromic/sulphuric or tartaric-sulphuric anodize plus chromate-free primer is standard aerospace practice; hard anodize is possible but coating is dark and slightly brittle, and shot peening is often used on machined SCC-critical 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).
Organic Coating
Equivalent designations
Standards and trade names that resolve to Aluminum 7449 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- A97449
- EN / DIN / Werkstoff-Nr.
- AW-7449
How much does 7449 cost?
7449 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.
7449 — frequently asked
What is 7449 used for?
7449 is typically used for aircraft wing plate, forged wing structure, high-strength structural components, machined wing ribs and spars, airframe forgings and fittings and thick plate for machined aerospace structure. In short: european 7055-class plate; good machinability for 7000 series; available in SCC-resistant T7x.
What is the yield strength of 7449?
7449 has a typical yield strength of 570 MPa (82.7 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 98% of aluminum grades. Strength varies by condition: see the 8 listed tempers.
Is 7449 easy to machine?
Yes — machinability is rated very good (78/100, better than 89% of aluminum grades). Machines well in T7x with sharp polished-flute carbide tools, high speed and flood or MQL coolant; plan symmetric stock removal and stress-relieved (T-x51/x52) material to control distortion in thin-web parts.
Can 7449 be welded?
Not readily — weldability is rated poor (18/100). Not suitable for fusion welding (hot cracking, severe HAZ softening and SCC); join by fasteners, bonding, or friction stir welding with qualified parameters.
What surface finishes work on 7449?
Chromic/sulphuric or tartaric-sulphuric anodize plus chromate-free primer is standard aerospace practice; hard anodize is possible but coating is dark and slightly brittle, and shot peening is often used on machined SCC-critical surfaces.
Can 7449 be formed, bent or molded?
Form in W or freshly quenched condition or hot; aged T6/T7x plate has low ductility and large minimum bend radii — cold forming is limited to gentle contours and stretch-forming of skins.
What is the maximum service temperature of 7449?
7449 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 7449-T7951 and 7449-O?
T7951 is the default condition — the standard supply condition for 7449 thick plate: near-peak strength with improved SCC/exfoliation over T6. O: mill/intermediate condition for heavy forming or re-heat-treat; not a service temper. Yield strength is 570 MPa in T7951 versus 110 MPa in O.
How much does 7449 cost?
7449 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)
- EN 485-2 Aluminium and aluminium alloys — Sheet, strip and plate: mechanical properties — CEN (2016)
- EN 755-2 Aluminium and aluminium alloys — Extruded rod/bar, tube and profiles: mechanical properties — CEN (2016)
- High-strength 7000-series aerospace plate and extrusion product data (7449/7040/7050) — Constellium (formerly Alcan/Pechiney) (2021)
- ASM Handbook Vol. 2: Properties and Selection — Nonferrous Alloys — ASM International (1990)
- MMPDS-17 typical property practice for 7000-series wrought products — Battelle/FAA (2022)
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.