Aluminum 8281 · temper
Aluminum 8281-O
Properties of the O condition, compared with the other 8281 tempers.
Pick for deep drawing, deadfold foil, laminating and any severe forming operation.
What is 8281-O?
8281-O is 8281 in the O temper — pick for deep drawing, deadfold foil, laminating and any severe forming operation. 8281-O has a yield strength of 35 MPa (5.08 ksi) and a tensile strength of 90 MPa (13.1 ksi) — weaker than 96% of aluminum grades. Elongation at break is 22% and the elastic modulus is 69 GPa (10 Msi). 8281-O has a density of 2.71 g/cm³ (0.0979 lb/in³), heavier than 51% of aluminum grades. It melts at 645°C (1,193 °F).
Advantages
- Forms and bends easily — 92/100, better than 94% of aluminum grades
- Conducts heat well — 210 W/m·K (121.3 BTU/hr·ft·°F), better than 93% of aluminum grades
- High electrical conductivity — 56 % IACS, better than 93% of aluminum grades
- Ductile — tolerates forming and impact — 22%, better than 91% of aluminum grades
Limitations
- Low strength — 35 MPa (5.08 ksi), worse than 96% of aluminum grades
- Difficult to machine — 28/100, worse than 94% of aluminum grades
8281-O properties
Typical room-temperature values for 8281-O — 11 properties are specific to this condition; the rest are grade-level values shared by every 8281 temper. Each bar shows where the value sits among the aluminum grades in FabDigit's library — further right is higher.
Physical3
8281-O has a density of 2.71 g/cm³ (0.0979 lb/in³), heavier than 51% of aluminum grades. It melts at 645°C (1,193 °F).
Mechanical10
8281-O has a yield strength of 35 MPa (5.08 ksi) and a tensile strength of 90 MPa (13.1 ksi) — weaker than 96% of aluminum grades. Elongation at break is 22% and the elastic modulus is 69 GPa (10 Msi).
Thermal6
8281-O is rated for continuous service to 150°C (302 °F). It conducts heat at 210 W/m·K (121.3 BTU/hr·ft·°F), better than 93% of aluminum grades. Thermal expansion is 23.6 µm/m·K (13.1 µin/in·°F).
Electrical3
8281-O conducts electricity at 56 % IACS, better than 93% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (58/100), better than 57% of aluminum grades.
Sustainability4
Producing a kilogram of 8281-O takes about 200 MJ of energy and emits 12 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 30%.
Manufacturability6
8281-O's machinability is poor (28/100, worse than 94% of aluminum grades); weldability very good (70/100); formability excellent (92/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 8281 tempers and conditions
8281 is also supplied in 8 other conditions. The full side-by-side table is on the 8281 overview.
- H19Highest-strength condition, used for thin hard foil/strip and tensioned coil applications; almost no formability left.160 MPa yield · 50 HB
- OPick for deep drawing, deadfold foil, laminating and any severe forming operation.35 MPa yield · 23 HB
Working with 8281-O
Is 8281 easy to machine?
Rarely machined — thin gauge; if machined use sharp polished-flute carbide, high speed, low feed and flood lubricant to avoid smearing in O temper.
Can 8281 be welded?
Non-heat-treatable, so no HAZ strength loss beyond loss of cold work; resistance/ultrasonic/laser welding or 1xxx–4xxx filler TIG works, but thin foil is usually joined by adhesive or seaming.
Can 8281 be formed, bent or molded?
Excellent cold formability in O/H22 (deep draw, deadfold, embossing); H18/H19 strip will crack on tight bends — form only along the rolling direction or re-anneal.
What surface finishes work on 8281?
Takes conversion coating, lacquer and laminating adhesives well; anodizing gives a grey, non-decorative film — degrease rolling oil thoroughly before coating.
8281 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.
| Element | Spec limit (wt %) |
|---|---|
| AlBalance; 8281 is a registered 8xxx-series composition — the individual Fe/Si/Cu/other limits per the AA 'Teal Sheets' / EN 573-3 registration are not reproduced here because they could not be verified | balance |
8281-O — frequently asked
What is 8281-O used for?
8281-O is typically used for bushings, sleeve bearings and wear inserts. In short: cast Sn-bearing bearing alloy.
What is the yield strength of 8281-O?
8281-O has a typical yield strength of 35 MPa (5.08 ksi) and a tensile strength of 90 MPa (13.1 ksi) — weaker than 96% of aluminum grades. Strength varies by condition: see the 9 listed tempers.
Is 8281-O easy to machine?
Not especially — machinability is rated poor (28/100, worse than 94% of aluminum grades). Rarely machined — thin gauge; if machined use sharp polished-flute carbide, high speed, low feed and flood lubricant to avoid smearing in O temper.
Can 8281-O be welded?
Yes — weldability is rated very good (70/100). Non-heat-treatable, so no HAZ strength loss beyond loss of cold work; resistance/ultrasonic/laser welding or 1xxx–4xxx filler TIG works, but thin foil is usually joined by adhesive or seaming.
What surface finishes work on 8281-O?
Takes conversion coating, lacquer and laminating adhesives well; anodizing gives a grey, non-decorative film — degrease rolling oil thoroughly before coating.
Can 8281-O be formed, bent or molded?
Excellent cold formability in O/H22 (deep draw, deadfold, embossing); H18/H19 strip will crack on tight bends — form only along the rolling direction or re-anneal.
What is the maximum service temperature of 8281-O?
8281-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.
Can FabDigit make parts in 8281-O?
Yes — 8281-O is available for sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- International Alloy Designations and Chemical Composition Limits for Wrought Aluminum Alloys (Teal Sheets) — The Aluminum Association (2018)
- EN 573-3 Aluminium and aluminium alloys — Chemical composition and form of wrought products — CEN (2019)
- EN 546-2 Aluminium and aluminium alloys — Foil — Mechanical properties — CEN (2007)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
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.