Aluminum 2025-O (Annealed)
Temper
AA 2025 · UNS A92025
Softest condition for maximum workability, straightening or re-forging before heat treatment.
Values for the O condition
Other 2025 tempers and conditions
2025 is listed in 4 conditions; see the grade overview at 2025.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
OThis page Annealed | Softest condition for maximum workability, straightening or re-forging before heat treatment. | 95 | 205 | 24 | 55 HB | 47 % IACS |
As fabricated | As-forged stock with no controlled thermal treatment — bought for subsequent solution treating and aging. | 140 | 260 | 20 | 70 HB | 45 % IACS |
Solution heat treated and naturally aged | Intermediate temper used when forgings must be straightened, coined or machined before final artificial aging. | 215 | 370 | 22 | 100 HB | 34 % IACS |
T6Default Solution heat treated and artificially aged | Standard delivery condition for 2025 forgings — full strength for propeller blades and structural forgings. | 255 | 400 | 19 | 110 HB | 40 % IACS |
What is 2025-O?
2025-O is 2025 in the O temper — softest condition for maximum workability, straightening or re-forging before heat treatment. 2025-O has a yield strength of 95 MPa (13.8 ksi) and a tensile strength of 205 MPa (29.7 ksi) — weaker than 86% of aluminum grades. Elongation at break is 24% and the elastic modulus is 72 GPa (10.4 Msi). 2025-O has a density of 2.81 g/cm³ (0.102 lb/in³), heavier than 86% of aluminum grades. It melts at 520°C (968 °F). T6 is the default condition FabDigit quotes; O is available on request or by drawing note.
Advantages
- Ductile — tolerates forming and impact — 24%, better than 92% of aluminum grades
- High electrical conductivity — 47 % IACS, better than 88% of aluminum grades
- Conducts heat well — 180 W/m·K (104 BTU/hr·ft·°F), better than 86% of aluminum grades
- Forms and bends easily — 70/100, better than 83% of aluminum grades
Limitations
- Low strength — 95 MPa (13.8 ksi), worse than 86% of aluminum grades
- Difficult to machine — 40/100, worse than 81% of aluminum grades
- Difficult to weld — 25/100, worse than 76% of aluminum grades
- Needs corrosion protection — 40/100, worse than 75% of aluminum grades
2025-O properties
Typical room-temperature values for 2025-O; 10 are specific to this condition. Other listed values are 2025 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
2025-O has a density of 2.81 g/cm³ (0.102 lb/in³), heavier than 86% of aluminum grades. It melts at 520°C (968 °F).
Mechanical11
2025-O has a yield strength of 95 MPa (13.8 ksi) and a tensile strength of 205 MPa (29.7 ksi) — weaker than 86% of aluminum grades. Elongation at break is 24% and the elastic modulus is 72 GPa (10.4 Msi).
Thermal6
2025-O is rated for continuous service to 150°C (302 °F). It conducts heat at 180 W/m·K (104 BTU/hr·ft·°F), better than 86% of aluminum grades. Thermal expansion is 22.7 µm/m·K (12.6 µin/in·°F).
Electrical3
2025-O conducts electricity at 47 % IACS, better than 88% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (40/100), worse than 75% of aluminum grades.
Sustainability4
Producing a kilogram of 2025-O takes about 205 MJ of energy and emits 12.5 kg of CO₂ — more than 76% of aluminum grades. Typical recycled content is 10%.
Manufacturability7
2025-O's machinability is fair (40/100, worse than 81% of aluminum grades); weldability poor (25/100); formability very good (70/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 2025-O
Is 2025 easy to machine?
Machines cleanly in T6 with sharp carbide tooling, high speeds and flood coolant; annealed/F material is gummy and needs positive-rake tools.
Can 2025 be welded?
Not recommended for arc welding (hot-cracking, loss of T6 properties) — join by riveting or bolting; resistance spot welding possible with qualified schedules.
Can 2025 be formed, bent or molded?
Excellent hot forgeability at roughly 420–460 °C, which is the alloy's reason for existence; cold forming should be done in O or T4 and followed by heat treatment.
What surface finishes work on 2025?
Anodize or chromate-convert plus prime for corrosion protection; shot peening improves fatigue life of forged blade sections.
2025 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 – 1.2 | 0.8 |
| Feimpurity limit | ≤ 1 | — |
| Cuprincipal strengthening element | 3.9 – 5 | 4.5 |
| Mn | 0.4 – 1.2 | 0.8 |
| Mg | ≤ 0.05 | — |
| Cr | ≤ 0.1 | — |
| Zn | ≤ 0.25 | — |
| Others (each) | ≤ 0.05 | — |
| Others (total) | ≤ 0.15 | — |
| Al | balance | — |
2025-O — frequently asked
What is 2025-O used for?
2025-O is typically used for propeller blades, forged aircraft components, forged airframe fittings, rotating forged blade sections, legacy aero-engine accessory forgings and machined-from-forging structural parts. In short: easy-forging 2000-series alloy; propeller-blade legacy grade; moderate strength, good ductility.
What is the yield strength of 2025-O?
2025-O has a typical yield strength of 95 MPa (13.8 ksi) and a tensile strength of 205 MPa (29.7 ksi) — weaker than 86% of aluminum grades. Strength varies by condition: see the 4 listed tempers.
Is 2025-O easy to machine?
Not especially — machinability is rated fair (40/100, worse than 81% of aluminum grades). Machines cleanly in T6 with sharp carbide tooling, high speeds and flood coolant; annealed/F material is gummy and needs positive-rake tools.
Can 2025-O be welded?
Not readily — weldability is rated poor (25/100). Not recommended for arc welding (hot-cracking, loss of T6 properties) — join by riveting or bolting; resistance spot welding possible with qualified schedules.
What surface finishes work on 2025-O?
Anodize or chromate-convert plus prime for corrosion protection; shot peening improves fatigue life of forged blade sections.
Can 2025-O be formed, bent or molded?
Excellent hot forgeability at roughly 420–460 °C, which is the alloy's reason for existence; cold forming should be done in O or T4 and followed by heat treatment.
What is the maximum service temperature of 2025-O?
2025-O 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 2025-T6 and 2025-O?
T6 is the default condition — standard delivery condition for 2025 forgings — full strength for propeller blades and structural forgings. O: softest condition for maximum workability, straightening or re-forging before heat treatment. Yield strength is 255 MPa in T6 versus 95 MPa in O.
Sources
- 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 and Special-Purpose Materials — ASM International (1990)
- Aluminum Standards and Data — The Aluminum Association (2017)
- Properties and Physical Metallurgy of Aluminum Alloys (J.E. Hatch, ed.) — ASM International (1984)
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.