Aluminum 6081-T651
Temper
AA 6081 · EN AW-6081, AW 6081
T651 = t6, stress relieved by stretching
Pick for machined plate/bar parts where dimensional stability after stock removal matters.
Values for the T651 condition
Other 6081 tempers and conditions
6081 is listed in 7 conditions; see the grade overview at 6081.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Pick for maximum formability before subsequent solution treatment and ageing. | 65 | 130 | 24 | 30 HB | 50 % IACS |
Solution heat treated and naturally aged | Pick when parts must still be bent, stretched or roll-formed after solution treatment, then optionally aged to T6. | 115 | 215 | 18 | 62 HB | 38 % IACS |
Solution heat treated and overaged (stabilized) | Rarely stocked; choose when thermal/dimensional stability and lower notch sensitivity outweigh peak strength. | 225 | 265 | 13 | 82 HB | 45 % IACS |
Cooled from hot working and artificially aged | Pick for thin-wall press-quenched profiles where slightly lower strength than T6 is acceptable and distortion must be minimised. | 230 | 275 | 9 | 85 HB | 43 % IACS |
T651This page T6, stress relieved by stretching | Pick for machined plate/bar parts where dimensional stability after stock removal matters. | 270 | 305 | 10 | 94 HB | 42 % IACS |
T6, stress relieved by stretching, minor straightening | Extruded rod/bar/profile version of T651 for straight, low-residual-stress machining stock. | 270 | 305 | 10 | 94 HB | 42 % IACS |
Solution heat treated and artificially aged | Default structural condition: highest strength with good corrosion resistance and anodizing quality. | 275 | 310 | 11 | 95 HB | 42 % IACS |
What is 6081-T651?
6081-T651 is 6081 in the T651 temper — pick for machined plate/bar parts where dimensional stability after stock removal matters. 6081-T651 has a yield strength of 270 MPa (39.2 ksi) and a tensile strength of 305 MPa (44.2 ksi) — stronger than 69% of aluminum grades. Elongation at break is 10% and the elastic modulus is 69 GPa (10 Msi). 6081-T651 has a density of 2.7 g/cm³ (0.0975 lb/in³), lighter than 59% of aluminum grades. It melts at 585°C (1,085 °F).
Advantages
- Conducts heat well — 170 W/m·K (98.2 BTU/hr·ft·°F), better than 82% of aluminum grades
- Polishes to a fine finish — 65/100, better than 82% of aluminum grades
- High electrical conductivity — 42 % IACS, better than 81% of aluminum grades
6081-T651 properties
Typical room-temperature values for 6081-T651; 20 are specific to this condition. Other listed values are 6081 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
6081-T651 has a density of 2.7 g/cm³ (0.0975 lb/in³), lighter than 59% of aluminum grades. It melts at 585°C (1,085 °F).
Mechanical13
6081-T651 has a yield strength of 270 MPa (39.2 ksi) and a tensile strength of 305 MPa (44.2 ksi) — stronger than 69% of aluminum grades. Elongation at break is 10% and the elastic modulus is 69 GPa (10 Msi).
Thermal6
6081-T651 is rated for continuous service to 150°C (302 °F). It conducts heat at 170 W/m·K (98.2 BTU/hr·ft·°F), better than 82% of aluminum grades. Thermal expansion is 23.4 µm/m·K (13 µin/in·°F).
Electrical3
6081-T651 conducts electricity at 42 % IACS, better than 81% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (66/100), better than 73% of aluminum grades.
Sustainability4
Producing a kilogram of 6081-T651 takes about 200 MJ of energy and emits 12.5 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 35%.
Manufacturability8
6081-T651's machinability is good (63/100, better than 58% of aluminum grades); weldability very good (78/100); formability fair (40/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 6081-T651
Is 6081 easy to machine?
Machines cleanly in T5/T6 with polished-flute carbide, high speed and >0.1 mm/tooth feed plus coolant to avoid built-up edge; avoid machining in O/T4 (gummy).
Can 6081 be welded?
Good MIG/TIG and friction-stir weldability with ER5356 (strength/marine) or ER4043 (crack resistance); HAZ drops to roughly T4 strength unless post-weld aged.
Can 6081 be formed, bent or molded?
Extrudes faster than 6082 thanks to low Mn/Cr; do tight bends in O or T4 and age afterwards, T6 tolerates only generous bend radii.
What surface finishes work on 6081?
Takes clear and colour anodizing well and accepts chromate-free pretreatment, powder coat and paint; use a chemical bright dip for decorative work as Si/Mn slightly grey the finish.
6081 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 |
|---|---|---|
| Simain strengthening partner with Mg (Mg2Si) | 0.7 – 1.1 | 0.9 |
| Fe | ≤ 0.5 | 0.25 |
| Cukept low for corrosion resistance | ≤ 0.1 | 0.03 |
| Mngrain-structure control | 0.1 – 0.45 | 0.25 |
| Mg | 0.6 – 1 | 0.8 |
| Cr | ≤ 0.1 | 0.03 |
| Zn | ≤ 0.2 | 0.05 |
| Ti | ≤ 0.15 | 0.02 |
| Others (each)total others 0.15 max | ≤ 0.05 | — |
| Al | balance | — |
6081-T651 — frequently asked
What is 6081-T651 used for?
6081-T651 is typically used for rail car structural profiles, automotive structural extrusions, architectural extrusions, scaffolding tubes and planks, general load-bearing profiles and welded frame assemblies. In short: extrusion grade like 6005A.
What is the yield strength of 6081-T651?
6081-T651 has a typical yield strength of 270 MPa (39.2 ksi) and a tensile strength of 305 MPa (44.2 ksi) — stronger than 69% of aluminum grades. Strength varies by condition: see the 7 listed tempers.
Is 6081-T651 easy to machine?
Reasonably — machinability is rated good (63/100, better than 58% of aluminum grades). Machines cleanly in T5/T6 with polished-flute carbide, high speed and >0.1 mm/tooth feed plus coolant to avoid built-up edge; avoid machining in O/T4 (gummy).
Can 6081-T651 be welded?
Yes — weldability is rated very good (78/100). Good MIG/TIG and friction-stir weldability with ER5356 (strength/marine) or ER4043 (crack resistance); HAZ drops to roughly T4 strength unless post-weld aged.
What surface finishes work on 6081-T651?
Takes clear and colour anodizing well and accepts chromate-free pretreatment, powder coat and paint; use a chemical bright dip for decorative work as Si/Mn slightly grey the finish.
Can 6081-T651 be formed, bent or molded?
Extrudes faster than 6082 thanks to low Mn/Cr; do tight bends in O or T4 and age afterwards, T6 tolerates only generous bend radii.
What is the maximum service temperature of 6081-T651?
6081-T651 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.
Can FabDigit make parts in 6081-T651?
Yes — 6081-T651 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 of wrought products — CEN (2019)
- EN 755-2 Aluminium and aluminium alloys — extruded rod/bar, tube and profiles: mechanical properties — CEN (2016)
- International Alloy Designations and Chemical Composition Limits for Wrought Aluminum (Teal Sheets) — The Aluminum Association (2018)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- EN 1999-1-1 Eurocode 9: Design of aluminium structures — CEN (2007)
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.