Aluminum 7150 · temper
Aluminum 7150-T7751
Properties of the T7751 condition, compared with the other 7150 tempers.
Choose when short-transverse SCC and exfoliation resistance must be improved while keeping ~90 % of peak strength.
What is 7150-T7751?
7150-T7751 is 7150 in the T7751 temper — choose when short-transverse SCC and exfoliation resistance must be improved while keeping ~90 % of peak strength. 7150-T7751 has a yield strength of 517 MPa (75 ksi) and a tensile strength of 565 MPa (81.9 ksi) — stronger than 97% of aluminum grades. Elongation at break is 11% and the elastic modulus is 71 GPa (10.3 Msi). 7150-T7751 has a density of 2.82 g/cm³ (0.102 lb/in³), heavier than 89% of aluminum grades. It melts at 477°C (891 °F). T651 is the default condition FabDigit quotes; T7751 is available on request or by drawing note.
Advantages
- High strength — 517 MPa (75 ksi), better than 97% of aluminum grades
- Tough — resists crack growth — 31 MPa·√m (28.2 ksi·√in), better than 80% of aluminum grades
Limitations
- Difficult to weld — 15/100, worse than 96% of aluminum grades
7150-T7751 properties
Typical room-temperature values for 7150-T7751 — 14 properties are specific to this condition; the rest are grade-level values shared by every 7150 temper. Each bar shows where the value sits among the aluminum grades in FabDigit's library — further right is higher.
Physical3
7150-T7751 has a density of 2.82 g/cm³ (0.102 lb/in³), heavier than 89% of aluminum grades. It melts at 477°C (891 °F).
Mechanical12
7150-T7751 has a yield strength of 517 MPa (75 ksi) and a tensile strength of 565 MPa (81.9 ksi) — stronger than 97% of aluminum grades. Elongation at break is 11% and the elastic modulus is 71 GPa (10.3 Msi).
Thermal6
7150-T7751 is rated for continuous service to 150°C (302 °F). It conducts heat at 155 W/m·K (89.6 BTU/hr·ft·°F), better than 71% of aluminum grades. Thermal expansion is 23.4 µm/m·K (13 µin/in·°F).
Electrical3
7150-T7751 conducts electricity at 40 % IACS, better than 72% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (45/100), worse than 62% of aluminum grades.
Sustainability4
Producing a kilogram of 7150-T7751 takes about 205 MJ of energy and emits 12.5 kg of CO₂ — more than 75% of aluminum grades. Typical recycled content is 5%.
Manufacturability7
7150-T7751's machinability is very good (70/100, better than 72% of aluminum grades); weldability poor (15/100); formability poor (20/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 7150 tempers and conditions
7150 is also supplied in 5 other conditions. The full side-by-side table is on the 7150 overview.
- T651DefaultStandard peak-aged, low-residual-stress plate temper for machined aerospace structure.572 MPa yield · 175 HB
- T77511Extruded stringers/frames needing high strength together with good exfoliation and SCC resistance.586 MPa yield · 172 HB
- T6Maximum strength condition for parts where SCC exposure and residual stress are controlled by design.579 MPa yield · 175 HB
- T6151Near-peak aged plate temper giving slightly better toughness/exfoliation behaviour than T651 at almost the same strength; used on upper wing skins.565 MPa yield · 170 HB
- T7751Choose when short-transverse SCC and exfoliation resistance must be improved while keeping ~90 % of peak strength.517 MPa yield · 160 HB
Working with 7150-T7751
Is 7150 easy to machine?
Machines very freely with sharp polished-flute carbide tooling, high speed and copious coolant; watch part distortion from residual stress in thick plate — prefer stretched (T651/T7751) stock and symmetric roughing passes.
Can 7150 be welded?
Not weldable by conventional MIG/TIG (hot cracking and severe HAZ strength loss); join by riveting, bolting or bonding — friction stir welding is feasible with qualified parameters.
Can 7150 be formed, bent or molded?
Form in the freshly quenched W condition or before aging; peak-aged plate has very limited cold formability and large minimum bend radii.
What surface finishes work on 7150?
Chromic or sulfuric anodize plus epoxy primer is the standard aerospace protection; shot peening and clad or Alclad layers improve fatigue and exfoliation resistance.
7150 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 | ≤ 0.12 | — |
| Fe | ≤ 0.15 | — |
| Cu | 1.9 – 2.5 | 2.2 |
| Mn | ≤ 0.1 | — |
| Mg | 2 – 2.7 | 2.3 |
| Cr | ≤ 0.04 | — |
| Zn | 5.9 – 6.9 | 6.4 |
| Ti | ≤ 0.06 | — |
| Zrdispersoid former, suppresses recrystallisation | 0.08 – 0.15 | 0.11 |
| Others (each) | ≤ 0.05 | — |
| Others (total) | ≤ 0.15 | — |
| Al | balance | — |
7150-T7751 — frequently asked
What is 7150-T7751 used for?
7150-T7751 is typically used for upper wing skins, spar caps and wing stringers, machined aerospace fittings, fuselage frames and bulkheads, high-load structural brackets and thick-plate machined airframe components. In short: premium 7xxx; higher strength than 7075.
What is the yield strength of 7150-T7751?
7150-T7751 has a typical yield strength of 517 MPa (75 ksi) and a tensile strength of 565 MPa (81.9 ksi) — stronger than 97% of aluminum grades. Strength varies by condition: see the 6 listed tempers.
Is 7150-T7751 easy to machine?
Yes — machinability is rated very good (70/100, better than 72% of aluminum grades). Machines very freely with sharp polished-flute carbide tooling, high speed and copious coolant; watch part distortion from residual stress in thick plate — prefer stretched (T651/T7751) stock and symmetric roughing passes.
Can 7150-T7751 be welded?
Not readily — weldability is rated poor (15/100). Not weldable by conventional MIG/TIG (hot cracking and severe HAZ strength loss); join by riveting, bolting or bonding — friction stir welding is feasible with qualified parameters.
What surface finishes work on 7150-T7751?
Chromic or sulfuric anodize plus epoxy primer is the standard aerospace protection; shot peening and clad or Alclad layers improve fatigue and exfoliation resistance.
Can 7150-T7751 be formed, bent or molded?
Form in the freshly quenched W condition or before aging; peak-aged plate has very limited cold formability and large minimum bend radii.
What is the maximum service temperature of 7150-T7751?
7150-T7751 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.
What is the difference between 7150-T651 and 7150-T7751?
T651 is the default condition — standard peak-aged, low-residual-stress plate temper for machined aerospace structure. T7751: choose when short-transverse SCC and exfoliation resistance must be improved while keeping ~90 % of peak strength. Yield strength is 572 MPa in T651 versus 517 MPa in T7751.
Can FabDigit make parts in 7150-T7751?
Yes — 7150-T7751 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
- International Alloy Designations and Chemical Composition Limits for Wrought Aluminum (Teal Sheets) — The Aluminum Association (2018)
- MMPDS-17 Metallic Materials Properties Development and Standardization — Battelle/FAA (2022)
- ASM Handbook Vol.2: Properties and Selection — Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol.19: Fatigue and Fracture — ASM International (1996)
- AMS 4252 / AMS 4306 series (7150 plate and extrusion) — SAE International (2018)
- High-strength 7xxx aerospace plate and extrusion data — Alcoa / Arconic / Constellium (2020)
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.