Aluminum 6061/Al2O3/20p-T651
Temper
also Duralcan W6A.20A
T651 = t6, stress relieved by stretching
Plate and rolled-bar version of T6 with stretch stress relief for dimensionally stable machined parts.
Values for the T651 condition
Other 6061/Al2O3/20p tempers and conditions
6061/Al2O3/20p is listed in 6 conditions; see the grade overview at 6061/Al2O3/20p.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Softest condition for maximum (still limited) formability and machining before heat treatment. | 75 | 150 | 10 | 48 HB | 38 % IACS |
As fabricated | Mill state straight from extrusion or rolling; use when the part will be solution treated and aged afterwards. | 165 | 275 | 4 | 72 HB | 35 % IACS |
Solution heat treated and naturally aged | Choose when some post-heat-treat forming or bending is needed and full T6 strength is not required. | 180 | 290 | 5 | 78 HB | 30 % IACS |
Cooled from hot working and artificially aged | Press-quenched extrusions aged without separate solution treatment — lower cost, moderate strength, less distortion. | 265 | 305 | 3 | 95 HB | 34 % IACS |
T6Default Solution heat treated and artificially aged | Standard stocked condition: peak strength, stiffness and wear resistance for extruded bar, tube and forgings. | 317 | 359 | 2.5 | 110 HB | 32 % IACS |
T651This page T6, stress relieved by stretching | Plate and rolled-bar version of T6 with stretch stress relief for dimensionally stable machined parts. | 325 | 365 | 2.5 | 112 HB | 32 % IACS |
What is 6061/Al2O3/20p-T651?
6061/Al2O3/20p-T651 is 6061/Al2O3/20p in the T651 temper — plate and rolled-bar version of T6 with stretch stress relief for dimensionally stable machined parts. 6061/Al2O3/20p-T651 has a yield strength of 325 MPa (47.1 ksi) and a tensile strength of 365 MPa (52.9 ksi) — stronger than 81% of aluminum grades. Elongation at break is 2.5% and the elastic modulus is 98 GPa (14.2 Msi). 6061/Al2O3/20p-T651 has a density of 2.9 g/cm³ (0.105 lb/in³), heavier than 98% of aluminum grades. It melts at 582°C (1,080 °F). T6 is the default condition FabDigit quotes; T651 is available on request or by drawing note.
Advantages
- Stiff — 98 GPa (14.2 Msi), better than 99% of aluminum grades
- High service temperature — 180°C (356 °F), better than 86% of aluminum grades
- High strength — 325 MPa (47.1 ksi), better than 81% of aluminum grades
Limitations
- Difficult to machine — 23/100, worse than 98% of aluminum grades
- Limited ductility — 2.5%, worse than 83% of aluminum grades
- Low fracture toughness — 17 MPa·√m (15.5 ksi·√in), worse than 83% of aluminum grades
6061/Al2O3/20p-T651 properties
Typical room-temperature values for 6061/Al2O3/20p-T651; 10 are specific to this condition. Other listed values are 6061/Al2O3/20p reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
6061/Al2O3/20p-T651 has a density of 2.9 g/cm³ (0.105 lb/in³), heavier than 98% of aluminum grades. It melts at 582°C (1,080 °F).
Mechanical16
6061/Al2O3/20p-T651 has a yield strength of 325 MPa (47.1 ksi) and a tensile strength of 365 MPa (52.9 ksi) — stronger than 81% of aluminum grades. Elongation at break is 2.5% and the elastic modulus is 98 GPa (14.2 Msi).
Thermal6
6061/Al2O3/20p-T651 is rated for continuous service to 180°C (356 °F). It conducts heat at 150 W/m·K (86.7 BTU/hr·ft·°F), better than 58% of aluminum grades. Thermal expansion is 18 µm/m·K (10 µin/in·°F).
Electrical3
6061/Al2O3/20p-T651 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 6061/Al2O3/20p-T651 takes about 215 MJ of energy and emits 13.5 kg of CO₂ — more than 93% of aluminum grades. Typical recycled content is 5%.
Manufacturability8
6061/Al2O3/20p-T651's machinability is poor (23/100, worse than 98% of aluminum grades); weldability fair (35/100); formability poor (20/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 6061/Al2O3/20p-T651
Is 6061/Al2O3/20p easy to machine?
Use PCD or CVD-diamond tooling at moderate speed and generous feed; carbide wears out in minutes and grinding requires diamond wheels.
Can 6061/Al2O3/20p be welded?
Friction stir welding and resistance welding give the best joints; GTAW/GMAW with 4043/4047 filler works but particle clustering and porosity cut joint ductility.
Can 6061/Al2O3/20p be formed, bent or molded?
Hot extrude/forge at 400–500 °C with low strain rates; cold forming is essentially limited to gentle large-radius bends in O or T4.
What surface finishes work on 6061/Al2O3/20p?
Grind or lap with diamond abrasives; anodizing gives a mottled, less protective film, so hard chrome, electroless Ni or paint is often preferred for cosmetic or wear surfaces.
6061/Al2O3/20p 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 |
|---|---|---|
| Al2O3reinforcement, vol% (≈27 wt%); balance below is the 6061 matrix composition in wt% | 18 – 22 | 20 |
| Mgmatrix | 0.8 – 1.2 | 1 |
| Simatrix | 0.4 – 0.8 | 0.6 |
| Cumatrix | 0.15 – 0.4 | 0.28 |
| Crmatrix | 0.04 – 0.35 | 0.2 |
| Feimpurity max | ≤ 0.7 | 0.3 |
| Mnimpurity max | ≤ 0.15 | 0.05 |
| Znimpurity max | ≤ 0.25 | 0.05 |
| Tiimpurity max | ≤ 0.15 | 0.05 |
| Almatrix balance | balance | — |
6061/Al2O3/20p-T651 — frequently asked
What is 6061/Al2O3/20p-T651 used for?
6061/Al2O3/20p-T651 is typically used for structural extrusions, sporting goods, industrial rollers and wear-resistant tubing. In short: extrudable aluminum MMC; stiffer than 6061-T6; friction stir weldable.
What is the yield strength of 6061/Al2O3/20p-T651?
6061/Al2O3/20p-T651 has a typical yield strength of 325 MPa (47.1 ksi) and a tensile strength of 365 MPa (52.9 ksi) — stronger than 81% of aluminum grades. Strength varies by condition: see the 6 listed tempers.
Is 6061/Al2O3/20p-T651 easy to machine?
Not especially — machinability is rated poor (23/100, worse than 98% of aluminum grades). Use PCD or CVD-diamond tooling at moderate speed and generous feed; carbide wears out in minutes and grinding requires diamond wheels.
Can 6061/Al2O3/20p-T651 be welded?
With care — weldability is rated fair (35/100). Friction stir welding and resistance welding give the best joints; GTAW/GMAW with 4043/4047 filler works but particle clustering and porosity cut joint ductility.
What surface finishes work on 6061/Al2O3/20p-T651?
Grind or lap with diamond abrasives; anodizing gives a mottled, less protective film, so hard chrome, electroless Ni or paint is often preferred for cosmetic or wear surfaces.
Can 6061/Al2O3/20p-T651 be formed, bent or molded?
Hot extrude/forge at 400–500 °C with low strain rates; cold forming is essentially limited to gentle large-radius bends in O or T4.
What is the maximum service temperature of 6061/Al2O3/20p-T651?
6061/Al2O3/20p-T651 is rated for continuous use to about 180°C (356 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 6061/Al2O3/20p-T6 and 6061/Al2O3/20p-O?
T6 is the default condition — standard stocked condition: peak strength, stiffness and wear resistance for extruded bar, tube and forgings. O: softest condition for maximum (still limited) formability and machining before heat treatment. Yield strength is 317 MPa in T6 versus 75 MPa in O.
Sources
- Duralcan Composite Data Book — W6A series (6061/Al2O3) — Alcan / Duralcan USA (1993)
- ASM Handbook Vol.21: Composites — Discontinuously Reinforced Aluminum — ASM International (2001)
- ASM Handbook Vol.2: Properties and Selection — Nonferrous Alloys (6061) — ASM International (1990)
- ANSI H35.1 / AA Teal Sheets — Alloy and Temper Designations — The Aluminum Association (2018)
- MatWeb entries for Duralcan W6A.20A aluminium-matrix composite — MatWeb LLC (2024)
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.