Aluminum 7050 · temper
Aluminum 7050 705.0-T1
Properties of the 705.0-T1 condition, compared with the other 7050 tempers.
Self-hardening Al-Zn-Mg sand/permanent-mold casting alloy 705.0 used as-cast and naturally aged, giving moderate strength without solution heat treatment plus good machinability and anodizing response.
What is 7050 705.0-T1?
7050 705.0-T1 is 7050 in the 705.0-T1 temper — self-hardening Al-Zn-Mg sand/permanent-mold casting alloy 705.0 used as-cast and naturally aged, giving moderate strength without solution heat treatment plus good machinability and anodizing response. 7050 705.0-T1 has a yield strength of 110 MPa (16 ksi) and a tensile strength of 200 MPa (29 ksi) — weaker than 81% of aluminum grades. Elongation at break is 5% and the elastic modulus is 70 GPa (10.2 Msi). 7050 705.0-T1 has a density of 2.76 g/cm³ (0.0997 lb/in³), heavier than 69% of aluminum grades. It melts at 600°C (1,112 °F).
Advantages
- Tough — resists crack growth — 36 MPa·√m (32.8 ksi·√in), better than 93% of aluminum grades
- Easy to machine — 72/100, better than 80% of aluminum grades
Limitations
- Low strength — 110 MPa (16 ksi), worse than 81% of aluminum grades
- Limited service temperature — 120°C (248 °F), worse than 79% of aluminum grades
7050 705.0-T1 properties
Typical room-temperature values for 7050 705.0-T1 — 27 properties are specific to this condition; the rest are grade-level values shared by every 7050 temper. Each bar shows where the value sits among the aluminum grades in FabDigit's library — further right is higher.
Physical3
7050 705.0-T1 has a density of 2.76 g/cm³ (0.0997 lb/in³), heavier than 69% of aluminum grades. It melts at 600°C (1,112 °F).
Mechanical12
7050 705.0-T1 has a yield strength of 110 MPa (16 ksi) and a tensile strength of 200 MPa (29 ksi) — weaker than 81% of aluminum grades. Elongation at break is 5% and the elastic modulus is 70 GPa (10.2 Msi).
Thermal6
7050 705.0-T1 is rated for continuous service to 120°C (248 °F). It conducts heat at 147 W/m·K (84.9 BTU/hr·ft·°F), better than 55% of aluminum grades. Thermal expansion is 24.1 µm/m·K (13.4 µin/in·°F).
Electrical3
7050 705.0-T1 conducts electricity at 35 % IACS, better than 52% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (55/100), worse than 51% of aluminum grades.
Sustainability4
Producing a kilogram of 7050 705.0-T1 takes about 205 MJ of energy and emits 13 kg of CO₂ — more than 75% of aluminum grades. Typical recycled content is 20%.
Manufacturability8
7050 705.0-T1's machinability is very good (72/100, better than 80% of aluminum grades); weldability good (60/100); formability poor (22/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 7050 tempers and conditions
7050 is also supplied in 10 other conditions. The full side-by-side table is on the 7050 overview.
- T7651Pick for thinner plate where higher strength is needed and good exfoliation resistance suffices; SCC resistance and toughness are lower than T7451.490 MPa yield · 147 HB
- T7451The workhorse condition for thick aerospace plate: best balance of strength, fracture toughness and SCC resistance, low residual stress so it stays flat during heavy machining.469 MPa yield · 140 HB
- T73510Extruded shapes/bar where maximum SCC resistance and low residual stress are required and minor straightening is not permitted.462 MPa yield · 140 HB
- T74General overaged forging temper (former T736) where stretching/compression stress relief is not specified; good SCC resistance in the short-transverse direction.441 MPa yield · 138 HB
- T7452Standard condition for 7050 die and hand forgings needing low residual stress plus good short-transverse SCC resistance.434 MPa yield · 135 HB
- 705.0-T5Casting alloy 705.0 given a low-temperature artificial age directly from the as-cast condition, raising strength and dimensional stability while keeping the alloy's good machinability, weldability and anodizing behaviour.125 MPa yield · 65 HB
- 705.0-T1Self-hardening Al-Zn-Mg sand/permanent-mold casting alloy 705.0 used as-cast and naturally aged, giving moderate strength without solution heat treatment plus good machinability and anodizing response.110 MPa yield · 60 HB
Working with 7050 705.0-T1
Is 7050 easy to machine?
Machines very freely in T74/T76 with sharp carbide, high speed and flood coolant/MQL; low residual stress of the ...51/...52 tempers is what makes deep pocket milling of monolithic parts practical.
Can 7050 be welded?
Not arc weldable (hot-cracking and severe HAZ SCC) — join by fasteners, adhesive bonding or friction stir welding with qualified procedures.
Can 7050 be formed, bent or molded?
Essentially a machining/forging alloy: form only in the W (as-quenched) or hot condition; cold bending in T7x risks cracking, use generous radii.
What surface finishes work on 7050?
Chromic/sulfuric or hard anodize plus primer for aerospace service; chemical conversion coating (Alodine/trivalent) is common, and the alloy takes paint well but gives a dull grey-yellow clear anodize.
7050 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 | 5.7 – 6.7 | 6.2 |
| Mg | 1.9 – 2.6 | 2.25 |
| Cu | 2 – 2.6 | 2.3 |
| Zrgrain-structure control instead of Cr | 0.08 – 0.15 | 0.11 |
| Fe | ≤ 0.15 | — |
| Si | ≤ 0.12 | — |
| Mn | ≤ 0.1 | — |
| Cr | ≤ 0.04 | — |
| Ti | ≤ 0.06 | — |
| Others (each)each | ≤ 0.05 | — |
| Others (total)total | ≤ 0.15 | — |
| Al | balance | — |
7050 705.0-T1 — frequently asked
What is 7050 705.0-T1 used for?
7050 705.0-T1 is typically used for aircraft bulkheads, fuselage frames, wing spars and ribs, landing-gear fittings, monolithic machined structural components and die and hand forgings for airframes. In short: crack resistant; heavy-duty aerospace.
What is the yield strength of 7050 705.0-T1?
7050 705.0-T1 has a typical yield strength of 110 MPa (16 ksi) and a tensile strength of 200 MPa (29 ksi) — weaker than 81% of aluminum grades. Strength varies by condition: see the 11 listed tempers.
Is 7050 705.0-T1 easy to machine?
Yes — machinability is rated very good (72/100, better than 80% of aluminum grades). Machines very freely in T74/T76 with sharp carbide, high speed and flood coolant/MQL; low residual stress of the ...51/...52 tempers is what makes deep pocket milling of monolithic parts practical.
Can 7050 705.0-T1 be welded?
Yes — weldability is rated good (60/100). Not arc weldable (hot-cracking and severe HAZ SCC) — join by fasteners, adhesive bonding or friction stir welding with qualified procedures.
What surface finishes work on 7050 705.0-T1?
Chromic/sulfuric or hard anodize plus primer for aerospace service; chemical conversion coating (Alodine/trivalent) is common, and the alloy takes paint well but gives a dull grey-yellow clear anodize.
Can 7050 705.0-T1 be formed, bent or molded?
Essentially a machining/forging alloy: form only in the W (as-quenched) or hot condition; cold bending in T7x risks cracking, use generous radii.
What is the maximum service temperature of 7050 705.0-T1?
7050 705.0-T1 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.
Can FabDigit make parts in 7050 705.0-T1?
Yes — 7050 705.0-T1 is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- Aluminum Association Teal Sheets — Registration Record of Alloys (composition of 7050) — The Aluminum Association (2018)
- ASTM B209 / AMS 4050 — 7050 plate mechanical properties — ASTM / SAE (2021)
- AMS 4107 / AMS 4108 — 7050 die and hand forgings — SAE International (2018)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- MMPDS-17 — Metallic Materials Properties Development and Standardization — Battelle/FAA (2022)
- 7050 aerospace plate datasheet — Alcoa / Arconic (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.