Aluminum 308.0-F (As fabricated)
Temper · default condition
AA 308.0 · UNS A03080 · BS LM21
Standard commercial condition: permanent-mold cast and used as-cast for general-purpose machined castings.
Values for the F condition
Other 308.0 tempers and conditions
308.0 is listed in 2 conditions; see the grade overview at 308.0.
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
F | Choose for larger or low-volume sand-cast parts; slower solidification gives coarser structure and 10–20% lower strength than chill casting. | 105 | 170 | 1 | 65 HB | 32 % IACS |
FDefaultThis page As fabricated | Standard commercial condition: permanent-mold cast and used as-cast for general-purpose machined castings. | 110 | 195 | 2 | 70 HB | 33 % IACS |
What is 308.0-F?
308.0-F is 308.0 in the F temper — standard commercial condition: permanent-mold cast and used as-cast for general-purpose machined castings. 308.0-F has a yield strength of 110 MPa (16 ksi) and a tensile strength of 195 MPa (28.3 ksi) — weaker than 81% of aluminum grades. Elongation at break is 2% and the elastic modulus is 71 GPa (10.3 Msi). 308.0-F has a density of 2.79 g/cm³ (0.101 lb/in³), heavier than 77% of aluminum grades. It melts at 521°C (970 °F).
Advantages
- High service temperature — 200°C (392 °F), better than 90% of aluminum grades
- Easy to machine — 72/100, better than 80% of aluminum grades
Limitations
- Hard to polish — 40/100, worse than 91% of aluminum grades
- Limited ductility — 2%, worse than 87% of aluminum grades
- Low fracture toughness — 17 MPa·√m (15.5 ksi·√in), worse than 83% of aluminum grades
- Low strength — 110 MPa (16 ksi), worse than 81% of aluminum grades
- Needs corrosion protection — 38/100, worse than 79% of aluminum grades
308.0-F properties
Typical room-temperature values for 308.0-F; 10 are specific to this condition. Other listed values are 308.0 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
308.0-F has a density of 2.79 g/cm³ (0.101 lb/in³), heavier than 77% of aluminum grades. It melts at 521°C (970 °F).
Mechanical13
308.0-F has a yield strength of 110 MPa (16 ksi) and a tensile strength of 195 MPa (28.3 ksi) — weaker than 81% of aluminum grades. Elongation at break is 2% and the elastic modulus is 71 GPa (10.3 Msi).
Thermal6
308.0-F is rated for continuous service to 200°C (392 °F). It conducts heat at 142 W/m·K (82 BTU/hr·ft·°F), better than 51% of aluminum grades. Thermal expansion is 21.5 µm/m·K (11.9 µin/in·°F).
Electrical3
308.0-F conducts electricity at 33 % IACS, worse than 57% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (38/100), worse than 79% of aluminum grades.
Sustainability4
Producing a kilogram of 308.0-F takes about 200 MJ of energy and emits 12 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 80%.
Manufacturability7
308.0-F's machinability is very good (72/100, better than 80% of aluminum grades); weldability poor (30/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 308.0-F
Is 308.0 easy to machine?
Machines freely with sharp PCD or coated carbide tooling; the eutectic Si is abrasive, so use high speed, moderate feed and flood coolant for good surface finish.
Can 308.0 be welded?
Poor fusion weldability — the 4–5% Cu promotes hot cracking; repairs are usually made with 4043/4145 filler under strict preheat control or by mechanical fastening.
Can 308.0 be formed, bent or molded?
Permanent-mold (gravity chill) casting alloy with excellent fluidity and low hot-tear tendency; also castable in sand. Not a wrought alloy — no cold forming.
What surface finishes work on 308.0?
Anodizing gives dark, non-decorative films; prefer chromate/conversion coating plus paint or powder coat, or electroless nickel for wear and corrosion protection.
308.0 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 | 5 – 6 | 5.5 |
| Cu | 4 – 5 | 4.5 |
| Fe | ≤ 1 | — |
| Mn | ≤ 0.5 | — |
| Mg | ≤ 0.1 | — |
| Zn | ≤ 1 | — |
| Ti | ≤ 0.25 | — |
| Others (each)each | ≤ 0.05 | — |
| Others (total)total | ≤ 0.35 | — |
| Al | balance | — |
308.0-F — frequently asked
What is 308.0-F used for?
308.0-F is typically used for general castings, housings and brackets. In short: free-machining cast aluminum; high-fluidity permanent-mold alloy; low-cost general-purpose casting.
What is the yield strength of 308.0-F?
308.0-F has a typical yield strength of 110 MPa (16 ksi) and a tensile strength of 195 MPa (28.3 ksi) — weaker than 81% of aluminum grades. Strength varies by condition: see the 2 listed tempers.
Is 308.0-F easy to machine?
Yes — machinability is rated very good (72/100, better than 80% of aluminum grades). Machines freely with sharp PCD or coated carbide tooling; the eutectic Si is abrasive, so use high speed, moderate feed and flood coolant for good surface finish.
Can 308.0-F be welded?
Not readily — weldability is rated poor (30/100). Poor fusion weldability — the 4–5% Cu promotes hot cracking; repairs are usually made with 4043/4145 filler under strict preheat control or by mechanical fastening.
What surface finishes work on 308.0-F?
Anodizing gives dark, non-decorative films; prefer chromate/conversion coating plus paint or powder coat, or electroless nickel for wear and corrosion protection.
Can 308.0-F be formed, bent or molded?
Permanent-mold (gravity chill) casting alloy with excellent fluidity and low hot-tear tendency; also castable in sand. Not a wrought alloy — no cold forming.
What is the maximum service temperature of 308.0-F?
308.0-F is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 308.0-F and 308.0 F-SAND?
F is the default condition — standard commercial condition: permanent-mold cast and used as-cast for general-purpose machined castings. F-SAND: choose for larger or low-volume sand-cast parts; slower solidification gives coarser structure and 10–20% lower strength than chill casting. Yield strength is 110 MPa in F versus 105 MPa in F-SAND.
Sources
- Registration Record of Aluminum Association Alloy Designations and Chemical Composition Limits for Aluminum Alloys in the Form of Castings and Ingot (Pink Sheets) — The Aluminum Association (2018)
- ASTM B108 / B26 — Aluminum-Alloy Permanent Mold and Sand Castings — ASTM International (2021)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
- ASM Specialty Handbook: Aluminum and Aluminum Alloys — ASM International (1993)
- BS 1490 LM21 — Aluminium and aluminium alloy ingots and castings — BSI (1988)
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.