Aluminum 6008-T66
Precip hard
AA 6008 · UNS A96008 · EN AlSiMgV
T66 = t6 with improved mechanical properties
Controlled-process ageing used by European extruders when higher guaranteed strength than T6 is specified.
Values for the T66 condition
Other 6008 tempers and conditions
6008 is listed in 7 conditions; see the grade overview at 6008.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Softest condition for deep drawing or severe bending before heat treatment. | 60 | 130 | 28 | 35 HB | 55 % IACS |
Solution heat treated and naturally aged | Standard supply condition for automotive body sheet and formed profiles; strength develops later during paint bake or T6 ageing. | 115 | 215 | 24 | 60 HB | 44 % IACS |
Solution heat treated and specially under-aged for formability | For profiles/sheet that must still be bent, hemmed or roll-formed after heat treatment. | 160 | 230 | 18 | 70 HB | 47 % IACS |
Cooled from hot working and artificially aged | Economical press-quench temper for thin architectural profiles where full T6 strength is not required. | 180 | 230 | 12 | 75 HB | 48 % IACS |
T6 variant, underaged | Choose when better bending/crash ductility is needed at slightly reduced strength. | 190 | 245 | 15 | 80 HB | 49 % IACS |
T6Default Solution heat treated and artificially aged | Default stocked condition: maximum strength for structural window/curtain-wall and automotive profiles. | 235 | 270 | 12 | 90 HB | 50 % IACS |
T66This page T6 with improved mechanical properties | Controlled-process ageing used by European extruders when higher guaranteed strength than T6 is specified. | 250 | 285 | 10 | 95 HB | 51 % IACS |
What is 6008-T66?
6008-T66 is 6008 in the T66 condition — controlled-process ageing used by European extruders when higher guaranteed strength than T6 is specified. 6008-T66 has a yield strength of 250 MPa (36.3 ksi) and a tensile strength of 285 MPa (41.3 ksi) — stronger than 65% of aluminum grades. Elongation at break is 10% and the elastic modulus is 69 GPa (10 Msi). 6008-T66 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). T6 is the default condition FabDigit quotes; T66 is available on request or by drawing note.
Advantages
- High electrical conductivity — 51 % IACS, better than 90% of aluminum grades
- Conducts heat well — 193 W/m·K (111.5 BTU/hr·ft·°F), better than 89% of aluminum grades
- Polishes to a fine finish — 65/100, better than 82% of aluminum grades
6008-T66 properties
Typical room-temperature values for 6008-T66; 22 are specific to this condition. Other listed values are 6008 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
6008-T66 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
6008-T66 has a yield strength of 250 MPa (36.3 ksi) and a tensile strength of 285 MPa (41.3 ksi) — stronger than 65% of aluminum grades. Elongation at break is 10% and the elastic modulus is 69 GPa (10 Msi).
Thermal6
6008-T66 is rated for continuous service to 150°C (302 °F). It conducts heat at 193 W/m·K (111.5 BTU/hr·ft·°F), better than 89% of aluminum grades. Thermal expansion is 23.4 µm/m·K (13 µin/in·°F).
Electrical3
6008-T66 conducts electricity at 51 % IACS, better than 90% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (64/100), better than 70% of aluminum grades.
Sustainability4
Producing a kilogram of 6008-T66 takes about 210 MJ of energy and emits 12.5 kg of CO₂ — more than 88% of aluminum grades. Typical recycled content is 35%.
Manufacturability7
6008-T66's machinability is good (62/100, better than 55% of aluminum grades); weldability very good (75/100); formability fair (40/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 6008-T66
Is 6008 easy to machine?
Machines freely in T5/T6 with sharp polished-flute carbide, high speed and generous coolant; T4/O tempers are gummy and tend to build up on edges.
Can 6008 be welded?
Readily GMAW/GTAW welded with 4043 (crack resistance) or 5356 (strength/anodizing match); expect HAZ softening to near-T4 levels unless post-weld aged.
Can 6008 be formed, bent or molded?
Extrudes at high speed thanks to the V-modified chemistry; form and hem in T4/T64, avoid tight-radius bending in T6 (use ≥3t radius).
What surface finishes work on 6008?
Excellent clear and colour anodizing and powder coating; mechanical polishing and brightening are good, chemical brightening acceptable due to low Cu.
6008 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 | 0.5 – 0.9 | 0.7 |
| Feimpurity limit | ≤ 0.35 | 0.2 |
| Cu | ≤ 0.3 | 0.1 |
| Mn | ≤ 0.3 | 0.1 |
| Mg | 0.4 – 0.7 | 0.55 |
| Cr | ≤ 0.3 | 0.05 |
| Zn | ≤ 0.2 | 0.05 |
| Tigrain refiner | ≤ 0.1 | 0.02 |
| Vcharacteristic addition of 6008 | 0.05 – 0.2 | 0.1 |
| Others (each)0.15 total | ≤ 0.05 | — |
| Al | balance | — |
6008-T66 — frequently asked
What is 6008-T66 used for?
6008-T66 is typically used for window and door frames, curtain-wall mullions and transoms, architectural extrusions and trim profiles, glazing bars and thermal-break profiles, handrail and balustrade sections and solar module frames. In short: high-speed extrusion 6000 series; low-copper, anodizes cleanly; medium strength, weldable.
What is the yield strength of 6008-T66?
6008-T66 has a typical yield strength of 250 MPa (36.3 ksi) and a tensile strength of 285 MPa (41.3 ksi) — stronger than 65% of aluminum grades. Strength varies by condition: see the 7 listed tempers.
Is 6008-T66 easy to machine?
Reasonably — machinability is rated good (62/100, better than 55% of aluminum grades). Machines freely in T5/T6 with sharp polished-flute carbide, high speed and generous coolant; T4/O tempers are gummy and tend to build up on edges.
Can 6008-T66 be welded?
Yes — weldability is rated very good (75/100). Readily GMAW/GTAW welded with 4043 (crack resistance) or 5356 (strength/anodizing match); expect HAZ softening to near-T4 levels unless post-weld aged.
What surface finishes work on 6008-T66?
Excellent clear and colour anodizing and powder coating; mechanical polishing and brightening are good, chemical brightening acceptable due to low Cu.
Can 6008-T66 be formed, bent or molded?
Extrudes at high speed thanks to the V-modified chemistry; form and hem in T4/T64, avoid tight-radius bending in T6 (use ≥3t radius).
What is the maximum service temperature of 6008-T66?
6008-T66 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 6008-T6 and 6008-O?
T6 is the default condition — default stocked condition: maximum strength for structural window/curtain-wall and automotive profiles. O: softest condition for deep drawing or severe bending before heat treatment. Yield strength is 235 MPa in T6 versus 60 MPa in O.
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 Extruded rod/bar, tube and profiles — Mechanical properties — CEN (2016)
- EN 485-2 Sheet, strip and plate — Mechanical properties — CEN (2016)
- ASM Handbook Vol. 2: Properties and Selection — Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol. 13B: Corrosion — Materials — ASM International (2005)
- Architectural/automotive 6000-series extrusion alloy datasheets — European extruders (e.g. Constellium, Hydro) (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.