Aluminum 2A16-T851
Temper
GB 2A16
T851 = t8, stress relieved by stretching
Choose for thick plate and machined structural parts where low residual stress and higher yield strength matter.
Values for the T851 condition
Other 2A16 tempers and conditions
2A16 is listed in 6 conditions; see the grade overview at 2A16.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Softest condition for cold forming, deep drawing and machining before heat treatment. | 80 | 185 | 20 | 48 HB | 44 % IACS |
As fabricated | Mill stock intended for subsequent forging and full solution + ageing treatment; properties not guaranteed. | 140 | 250 | 14 | 70 HB | 40 % IACS |
Solution heat treated and naturally aged | Pick when parts must be formed or riveted after solution treatment and only moderate strength is needed. | 185 | 340 | 16 | 90 HB | 28 % IACS |
T6, heat treated by the user | Used for parts formed or welded in the soft state and then given a full heat treatment cycle. | 260 | 395 | 10 | 108 HB | 30 % IACS |
T6Default Solution heat treated and artificially aged | Standard supply condition: peak strength plus the best retention of strength at 200–250 °C. | 265 | 400 | 10 | 110 HB | 30 % IACS |
T851This page T8, stress relieved by stretching | Choose for thick plate and machined structural parts where low residual stress and higher yield strength matter. | 320 | 425 | 8 | 120 HB | 32 % IACS |
What is 2A16-T851?
2A16-T851 is 2A16 in the T851 temper — choose for thick plate and machined structural parts where low residual stress and higher yield strength matter. 2A16-T851 has a yield strength of 320 MPa (46.4 ksi) and a tensile strength of 425 MPa (61.6 ksi) — stronger than 80% of aluminum grades. Elongation at break is 8% and the elastic modulus is 72 GPa (10.4 Msi). 2A16-T851 has a density of 2.84 g/cm³ (0.103 lb/in³), heavier than 93% of aluminum grades. It melts at 540°C (1,004 °F). T6 is the default condition FabDigit quotes; T851 is available on request or by drawing note.
Advantages
- High service temperature — 250°C (482 °F), better than 97% of aluminum grades
- Easy to machine — 73/100, better than 85% of aluminum grades
- Tough — resists crack growth — 32 MPa·√m (29.1 ksi·√in), better than 83% of aluminum grades
- High strength — 320 MPa (46.4 ksi), better than 80% of aluminum grades
Limitations
- Needs corrosion protection — 33/100, worse than 91% of aluminum grades
2A16-T851 properties
Typical room-temperature values for 2A16-T851; 10 are specific to this condition. Other listed values are 2A16 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
2A16-T851 has a density of 2.84 g/cm³ (0.103 lb/in³), heavier than 93% of aluminum grades. It melts at 540°C (1,004 °F).
Mechanical13
2A16-T851 has a yield strength of 320 MPa (46.4 ksi) and a tensile strength of 425 MPa (61.6 ksi) — stronger than 80% of aluminum grades. Elongation at break is 8% and the elastic modulus is 72 GPa (10.4 Msi).
Thermal6
2A16-T851 is rated for continuous service to 250°C (482 °F). It conducts heat at 125 W/m·K (72.2 BTU/hr·ft·°F), worse than 72% of aluminum grades. Thermal expansion is 22.6 µm/m·K (12.6 µin/in·°F).
Electrical3
2A16-T851 conducts electricity at 32 % IACS, worse than 63% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is poor (33/100), worse than 91% of aluminum grades.
Sustainability4
Producing a kilogram of 2A16-T851 takes about 210 MJ of energy and emits 12.5 kg of CO₂ — more than 88% of aluminum grades. Typical recycled content is 8%.
Manufacturability7
2A16-T851's machinability is very good (73/100, better than 85% of aluminum grades); weldability very good (72/100); formability fair (35/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 2A16-T851
Is 2A16 easy to machine?
Machines cleanly in T6/T851 with sharp carbide tools, high speed and flood coolant; gummy and prone to built-up edge in the O temper.
Can 2A16 be welded?
One of the better-welding 2000-series alloys — TIG/MIG or FSW with ER2319-type filler; expect ~60 % joint efficiency as-welded unless re-solution treated and aged.
Can 2A16 be formed, bent or molded?
Form in O or freshly quenched T4 condition; T6/T851 stock has limited bend ductility (min bend radius ≥3–4 t) and should be hot formed at 300–400 °C if severe.
What surface finishes work on 2A16?
Chromic or sulfuric anodize plus primer/paint, or alclad sheet, is normally specified; conversion coating (chromate/Cr-free) before painting is standard because bare surfaces pit readily.
2A16 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 |
|---|---|---|
| Cumain strengthening element (Al₂Cu) | 6 – 7 | 6.5 |
| Mngrain/recrystallisation control, heat resistance | 0.4 – 0.8 | 0.6 |
| Tigrain refinement, weld cracking resistance | 0.1 – 0.2 | 0.15 |
| Siimpurity limit | ≤ 0.3 | — |
| Feimpurity limit | ≤ 0.3 | — |
| Mgkept low (2A17 is the Mg-bearing variant) | ≤ 0.05 | — |
| Znimpurity limit | ≤ 0.1 | — |
| Niimpurity limit | ≤ 0.1 | — |
| Other (each)others total ≤0.15 | ≤ 0.05 | — |
| Al | balance | — |
2A16-T851 — frequently asked
What is 2A16-T851 used for?
2A16-T851 is typically used for elevated-temperature structural parts, engine nacelle components, welded structural assemblies above 150 °C, heat-resistant sheet and plate skins, forged high-temperature fittings and machined brackets near hot zones. In short: most weldable 2000-series grade; 250 °C service capability; 2219-class heat resistance.
What is the yield strength of 2A16-T851?
2A16-T851 has a typical yield strength of 320 MPa (46.4 ksi) and a tensile strength of 425 MPa (61.6 ksi) — stronger than 80% of aluminum grades. Strength varies by condition: see the 6 listed tempers.
Is 2A16-T851 easy to machine?
Yes — machinability is rated very good (73/100, better than 85% of aluminum grades). Machines cleanly in T6/T851 with sharp carbide tools, high speed and flood coolant; gummy and prone to built-up edge in the O temper.
Can 2A16-T851 be welded?
Yes — weldability is rated very good (72/100). One of the better-welding 2000-series alloys — TIG/MIG or FSW with ER2319-type filler; expect ~60 % joint efficiency as-welded unless re-solution treated and aged.
What surface finishes work on 2A16-T851?
Chromic or sulfuric anodize plus primer/paint, or alclad sheet, is normally specified; conversion coating (chromate/Cr-free) before painting is standard because bare surfaces pit readily.
Can 2A16-T851 be formed, bent or molded?
Form in O or freshly quenched T4 condition; T6/T851 stock has limited bend ductility (min bend radius ≥3–4 t) and should be hot formed at 300–400 °C if severe.
What is the maximum service temperature of 2A16-T851?
2A16-T851 is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 2A16-T6 and 2A16-O?
T6 is the default condition — standard supply condition: peak strength plus the best retention of strength at 200–250 °C. O: softest condition for cold forming, deep drawing and machining before heat treatment. Yield strength is 265 MPa in T6 versus 80 MPa in O.
Sources
- ASM Handbook Vol.2: Properties and Selection — Nonferrous Alloys (2219 data used as analogue) — ASM International (1990)
- MMPDS-17 aluminium 2219 property tables (analogue) — Battelle/FAA (2022)
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.