Aluminum 7012 · temper
Aluminum 7012-T651
Properties of the T651 condition, compared with the other 7012 tempers.
Choose for thick plate that will be heavily machined — stretch stress-relief minimises distortion of mould and jig plates.
What is 7012-T651?
7012-T651 is 7012 in the T651 temper — choose for thick plate that will be heavily machined — stretch stress-relief minimises distortion of mould and jig plates. 7012-T651 has a yield strength of 495 MPa (71.8 ksi) and a tensile strength of 540 MPa (78.3 ksi) — stronger than 96% of aluminum grades. Elongation at break is 9% and the elastic modulus is 71 GPa (10.3 Msi). 7012-T651 has a density of 2.81 g/cm³ (0.102 lb/in³), heavier than 86% of aluminum grades. It melts at 480°C (896 °F).
Advantages
- High strength — 495 MPa (71.8 ksi), better than 96% of aluminum grades
- Easy to machine — 75/100, better than 86% of aluminum grades
Limitations
- Needs corrosion protection — 33/100, worse than 90% of aluminum grades
- Difficult to weld — 22/100, worse than 83% of aluminum grades
- Limited service temperature — 120°C (248 °F), worse than 79% of aluminum grades
7012-T651 properties
Typical room-temperature values for 7012-T651 — 8 properties are specific to this condition; the rest are grade-level values shared by every 7012 temper. Each bar shows where the value sits among the aluminum grades in FabDigit's library — further right is higher.
Physical3
7012-T651 has a density of 2.81 g/cm³ (0.102 lb/in³), heavier than 86% of aluminum grades. It melts at 480°C (896 °F).
Mechanical13
7012-T651 has a yield strength of 495 MPa (71.8 ksi) and a tensile strength of 540 MPa (78.3 ksi) — stronger than 96% of aluminum grades. Elongation at break is 9% and the elastic modulus is 71 GPa (10.3 Msi).
Thermal6
7012-T651 is rated for continuous service to 120°C (248 °F). It conducts heat at 135 W/m·K (78 BTU/hr·ft·°F), worse than 58% of aluminum grades. Thermal expansion is 23.4 µm/m·K (13 µin/in·°F).
Electrical3
7012-T651 conducts electricity at 32 % IACS, worse than 63% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is poor (33/100), worse than 90% of aluminum grades.
Sustainability4
Producing a kilogram of 7012-T651 takes about 205 MJ of energy and emits 12.5 kg of CO₂ — more than 75% of aluminum grades. Typical recycled content is 20%.
Manufacturability7
7012-T651's machinability is very good (75/100, better than 86% of aluminum grades); weldability poor (22/100); 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 7012 tempers and conditions
7012 is also supplied in 5 other conditions. The full side-by-side table is on the 7012 overview.
- T6Standard stock condition — maximum strength for structural extrusions, plate and machined parts in dry/protected service.510 MPa yield · 160 HB
- T651Choose for thick plate that will be heavily machined — stretch stress-relief minimises distortion of mould and jig plates.495 MPa yield · 158 HB
- T76Compromise temper: most of the T6 strength with much better exfoliation/SCC behaviour for thin plate and profiles.455 MPa yield · 150 HB
- T73Pick for humid, marine or sustained-tension service where stress-corrosion cracking must be eliminated, accepting ~12 % lower strength.420 MPa yield · 140 HB
- T4Intermediate condition used when some forming or straightening is needed before final artificial ageing.300 MPa yield · 125 HB
Working with 7012-T651
Is 7012 easy to machine?
Machines very freely in T6/T651 with sharp polished PCD or uncoated carbide, high speed and generous coolant; chips are short and finishes excellent.
Can 7012 be welded?
Not recommended for fusion welding (hot cracking, large HAZ strength loss) — join by bolting, bonding or friction-stir welding with post-weld ageing.
Can 7012 be formed, bent or molded?
Form in F/T4 only; T6 material has low ductility and bend radii must be generous — cold bending of aged plate risks cracking.
What surface finishes work on 7012?
Takes clear and hard anodizing well (slightly grey tone), chromate/Ti-Zr conversion coatings and primers; avoid direct contact with steel/CFRP without insulation.
7012 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 | ≤ 0.15 | 0.06 |
| Feimpurity limit | ≤ 0.25 | 0.12 |
| Cu | 0.8 – 1.2 | 1 |
| Mn | ≤ 0.1 | 0.03 |
| Mg | 1.8 – 2.2 | 2 |
| Cr | ≤ 0.05 | 0.02 |
| Znprincipal hardening addition | 5.8 – 6.5 | 6.1 |
| Zrgrain-structure control (dispersoids) | 0.08 – 0.2 | 0.14 |
| Ti | ≤ 0.05 | 0.02 |
| Other, each | ≤ 0.05 | — |
| Other, total | ≤ 0.15 | — |
| Al | balance | — |
7012-T651 — frequently asked
What is 7012-T651 used for?
7012-T651 is typically used for aerospace forgings, helicopter rotor parts, high-strength structural extrusions, mould and tooling plate, machined structural fittings from thick plate and sporting goods frames. In short: european aero forging alloy.
What is the yield strength of 7012-T651?
7012-T651 has a typical yield strength of 495 MPa (71.8 ksi) and a tensile strength of 540 MPa (78.3 ksi) — stronger than 96% of aluminum grades. Strength varies by condition: see the 6 listed tempers.
Is 7012-T651 easy to machine?
Yes — machinability is rated very good (75/100, better than 86% of aluminum grades). Machines very freely in T6/T651 with sharp polished PCD or uncoated carbide, high speed and generous coolant; chips are short and finishes excellent.
Can 7012-T651 be welded?
Not readily — weldability is rated poor (22/100). Not recommended for fusion welding (hot cracking, large HAZ strength loss) — join by bolting, bonding or friction-stir welding with post-weld ageing.
What surface finishes work on 7012-T651?
Takes clear and hard anodizing well (slightly grey tone), chromate/Ti-Zr conversion coatings and primers; avoid direct contact with steel/CFRP without insulation.
Can 7012-T651 be formed, bent or molded?
Form in F/T4 only; T6 material has low ductility and bend radii must be generous — cold bending of aged plate risks cracking.
What is the maximum service temperature of 7012-T651?
7012-T651 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 7012-T651?
Yes — 7012-T651 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)
- EN 573-3 Aluminium and aluminium alloys — Chemical composition — CEN (2019)
- EN 755-2 Aluminium alloy extruded rod/bar, tube and profiles — Mechanical properties — CEN (2016)
- ASM Handbook Vol. 2: Properties and Selection — Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol. 13B: Corrosion — Materials (aluminium alloys) — ASM International (2005)
- High-strength 7xxx extrusion and plate alloy datasheets (Al-Zn-Mg-Cu-Zr) — Constellium / Alcoa (2021)
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.