Aluminum 7020-T6511
Temper
AA 7020 · UNS A97020 · EN AW-7020, 3.4335 · BS H17
T6511 = t6, stress relieved by stretching, minor straightening
Most common bar/extrusion temper for machined 7020 components needing straightness plus low residual stress.
Values for the T6511 condition
Other 7020 tempers and conditions
7020 is listed in 10 conditions; see the grade overview at 7020.
Compare all 10 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Choose for maximum formability before forming and re-solution treating; strength is low and unstable against natural aging. | 115 | 225 | 17 | 60 HB | 40 % IACS |
Solution heat treated and naturally aged | Pick when parts must be bent/formed after heat treatment and then allowed to age (or later artificially aged) to full strength. | 210 | 330 | 16 | 92 HB | 29 % IACS |
T4, stress relieved by stretching | 7020 plate solution-treated, stretched to relieve residual stress, then naturally aged — moderate strength with good formability and low machining distortion. | 215 | 340 | 16 | 88 HB | 29 % IACS |
Solution heat treated and overaged for stress-corrosion resistance | Specify for thick sections or chloride/humid service where stress-corrosion and exfoliation resistance outweigh a ~10 % strength loss. | 290 | 350 | 13 | 108 HB | 37 % IACS |
Cooled from hot working and artificially aged | Economical route for thin-wall extrusions: 7020 is press-quenchable, so aging directly off the press gives near-T6 strength with less distortion. | 310 | 360 | 11 | 112 HB | 32 % IACS |
T6, heat treated by the user | 7020 re-solution-treated and artificially aged after forming or welding, giving T6-level peak-aged strength without producer stress relief. | 315 | 375 | 11 | 113 HB | 32 % IACS |
T6, stress relieved by stretching | Plate condition for machined structural parts where flatness and low residual stress matter. | 330 | 380 | 11 | 118 HB | 32 % IACS |
Solution heat treated and artificially aged | Standard supply condition: peak strength for welded structural work, bridges, armour and frames. | 340 | 385 | 12 | 120 HB | 32 % IACS |
Solution treated, stretched, aged; no further straightening | Extruded profiles with controlled stretch for low residual stress in long machined members. | 345 | 385 | 11 | 120 HB | 32 % IACS |
T6511This page T6, stress relieved by stretching, minor straightening | Most common bar/extrusion temper for machined 7020 components needing straightness plus low residual stress. | 345 | 385 | 11 | 120 HB | 32 % IACS |
What is 7020-T6511?
7020-T6511 is 7020 in the T6511 temper — most common bar/extrusion temper for machined 7020 components needing straightness plus low residual stress. 7020-T6511 has a yield strength of 345 MPa (50 ksi) and a tensile strength of 385 MPa (55.8 ksi) — stronger than 83% of aluminum grades. Elongation at break is 11% and the elastic modulus is 70 GPa (10.2 Msi). 7020-T6511 has a density of 2.78 g/cm³ (0.1 lb/in³), heavier than 74% of aluminum grades. It melts at 605°C (1,121 °F).
Advantages
- High strength — 345 MPa (50 ksi), better than 83% of aluminum grades
- Tough — resists crack growth — 32 MPa·√m (29.1 ksi·√in), better than 83% of aluminum grades
Limitations
- Limited service temperature — 120°C (248 °F), worse than 79% of aluminum grades
7020-T6511 properties
Typical room-temperature values for 7020-T6511; 22 are specific to this condition. Other listed values are 7020 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
7020-T6511 has a density of 2.78 g/cm³ (0.1 lb/in³), heavier than 74% of aluminum grades. It melts at 605°C (1,121 °F).
Mechanical13
7020-T6511 has a yield strength of 345 MPa (50 ksi) and a tensile strength of 385 MPa (55.8 ksi) — stronger than 83% of aluminum grades. Elongation at break is 11% and the elastic modulus is 70 GPa (10.2 Msi).
Thermal6
7020-T6511 is rated for continuous service to 120°C (248 °F). It conducts heat at 125 W/m·K (72.2 BTU/hr·ft·°F), worse than 72% of aluminum grades. Thermal expansion is 23.1 µm/m·K (12.8 µin/in·°F).
Electrical3
7020-T6511 conducts electricity at 32 % IACS, worse than 63% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (55/100), worse than 51% of aluminum grades.
Sustainability4
Producing a kilogram of 7020-T6511 takes about 200 MJ of energy and emits 12.5 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 25%.
Manufacturability8
7020-T6511's machinability is good (57/100, worse than 55% of aluminum grades); weldability very good (76/100); formability poor (30/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 7020-T6511
Is 7020 easy to machine?
Machines well in T6/T651 with sharp carbide tools, high speed and flood coolant; softer T4/O tempers tend to smear and build up on the edge.
Can 7020 be welded?
The most weldable 7000-series alloy — MIG/TIG with 5356 or 5183 filler, HAZ recovers most strength by natural re-aging over 2–4 weeks; avoid restraint and pre-heat to limit SCC in the HAZ.
Can 7020 be formed, bent or molded?
Form in O or T4; T6 bends need generous radii (≥3–4 t) as ductility is limited; hot forming above ~350 °C degrades the temper.
What surface finishes work on 7020?
Anodizes to a slightly grey/yellow clear film and takes hard coat well; chromate/chromate-free conversion coatings and paint are common on structural welded assemblies to combat exfoliation.
7020 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 | ≤ 0.35 | 0.15 |
| Fe | ≤ 0.4 | 0.25 |
| Cukept low for weldability | ≤ 0.2 | 0.1 |
| Mn | 0.05 – 0.5 | 0.25 |
| Mg | 1 – 1.4 | 1.2 |
| Cr | 0.1 – 0.35 | 0.2 |
| Zn | 4 – 5 | 4.5 |
| ZrZr+Ti 0.08–0.25 | 0.08 – 0.2 | 0.14 |
| Ti | ≤ 0.2 | 0.05 |
| Others (each)total 0.15 max | ≤ 0.05 | — |
| Al | balance | — |
7020-T6511 — frequently asked
What is 7020-T6511 used for?
7020-T6511 is typically used for bridges, cranes and military vehicles. In short: weldable structural 7000 series.
What is the yield strength of 7020-T6511?
7020-T6511 has a typical yield strength of 345 MPa (50 ksi) and a tensile strength of 385 MPa (55.8 ksi) — stronger than 83% of aluminum grades. Strength varies by condition: see the 10 listed tempers.
Is 7020-T6511 easy to machine?
Reasonably — machinability is rated good (57/100, worse than 55% of aluminum grades). Machines well in T6/T651 with sharp carbide tools, high speed and flood coolant; softer T4/O tempers tend to smear and build up on the edge.
Can 7020-T6511 be welded?
Yes — weldability is rated very good (76/100). The most weldable 7000-series alloy — MIG/TIG with 5356 or 5183 filler, HAZ recovers most strength by natural re-aging over 2–4 weeks; avoid restraint and pre-heat to limit SCC in the HAZ.
What surface finishes work on 7020-T6511?
Anodizes to a slightly grey/yellow clear film and takes hard coat well; chromate/chromate-free conversion coatings and paint are common on structural welded assemblies to combat exfoliation.
Can 7020-T6511 be formed, bent or molded?
Form in O or T4; T6 bends need generous radii (≥3–4 t) as ductility is limited; hot forming above ~350 °C degrades the temper.
What is the maximum service temperature of 7020-T6511?
7020-T6511 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 7020-T6511?
Yes — 7020-T6511 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
- EN 573-3 Aluminium and aluminium alloys — chemical composition — CEN (2019)
- EN 485-2 Aluminium sheet, strip and plate — mechanical properties — CEN (2018)
- EN 755-2 Aluminium extruded rod/bar, tube and profiles — mechanical properties — CEN (2016)
- EN 515 Aluminium wrought products — temper designations — CEN (2017)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol. 13B / Vol. 19 — Corrosion and Fatigue of Aluminium Alloys — ASM International (2005)
- EN AW-7020 (AlZn4.5Mg1) plate and extrusion datasheets — European aluminium producers (2023)
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.