Aluminum 2218
AA 2218 · UNS A92218 · EN AW-2218, AW 2218
2218 is a nickel-bearing Al-Cu-Mg-Ni forging alloy, heat-treatable and closely related to 2618/2A70, in which Al₂Cu together with Ni- and Fe-rich intermetallics holds strength at 150–250 °C.
Values for the T61 condition
2218 tempers and conditions
2218 is supplied in 4 conditions, soft to hard. T61 is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution heat treated and fully overaged/stabilized | Choose for pistons and hot-running parts where growth-free dimensional stability above 200 °C matters more than peak strength. | 255 | 330 | 11 | 95 HB | 40 % IACS |
Solution heat treated and overaged | Intermediate overaged temper trading some strength for better dimensional stability at elevated temperature. | 275 | 345 | 11 | 105 HB | 39 % IACS |
T61Default T6 variant, underaged | Standard high-strength temper for 2218 pistons and engine forgings; mild quench limits distortion and residual stress. | 305 | 405 | 11 | 115 HB | 38 % IACS |
Solution heat treated and artificially aged | Generic peak-aged designation; for 2218 forgings it is supplied in practice as the T61 variant. | 305 | 405 | 11 | 115 HB | 38 % IACS |
What is 2218?
2218 is a nickel-bearing Al-Cu-Mg-Ni forging alloy, heat-treatable and closely related to 2618/2A70, in which Al₂Cu together with Ni- and Fe-rich intermetallics holds strength at 150–250 °C. Default values are 305 MPa yield, 405 MPa tensile, 11 % elongation, 115 HB and 147 W/m·K with service to about 200 °C, suiting forged pistons, cylinder heads, turbocharger impellers and jet-engine rings. Corrosion resistance is modest and needs cladding or coating, fusion welding is crack-sensitive, cold formability is poor, and supply is limited to forgings and bar; 2618 is more widely stocked. 2218 has a density of 2.81 g/cm³ (0.102 lb/in³), heavier than 86% of aluminum grades. It melts at 505°C (941 °F). 2218 has a yield strength of 305 MPa (44.2 ksi) and a tensile strength of 405 MPa (58.7 ksi) — stronger than 77% of aluminum grades. Elongation at break is 11% and the elastic modulus is 74 GPa (10.7 Msi).
What is 2218 used for?
- Forged engine pistons
- Cylinder heads
- Turbocharger impellers
- Jet-engine rings
- High-temperature forged brackets
- Hot-end machined engine hardware
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
- High strength — 305 MPa (44.2 ksi), better than 77% of aluminum grades
Limitations
- Needs corrosion protection — 33/100, worse than 91% of aluminum grades
- Difficult to weld — 22/100, worse than 83% of aluminum grades
2218 properties
Typical room-temperature values for 2218-T61; bars are the position among aluminum grades.
Physical3
2218 has a density of 2.81 g/cm³ (0.102 lb/in³), heavier than 86% of aluminum grades. It melts at 505°C (941 °F).
Mechanical11
2218 has a yield strength of 305 MPa (44.2 ksi) and a tensile strength of 405 MPa (58.7 ksi) — stronger than 77% of aluminum grades. Elongation at break is 11% and the elastic modulus is 74 GPa (10.7 Msi).
Thermal6
2218 is rated for continuous service to 200°C (392 °F). It conducts heat at 147 W/m·K (84.9 BTU/hr·ft·°F), better than 55% of aluminum grades. Thermal expansion is 22.4 µm/m·K (12.4 µin/in·°F).
Electrical3
2218 conducts electricity at 38 % IACS, better than 61% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is poor (33/100), worse than 91% of aluminum grades.
Sustainability4
Producing a kilogram of 2218 takes about 205 MJ of energy and emits 12.5 kg of CO₂ — more than 76% of aluminum grades. Typical recycled content is 20%.
Manufacturability6
2218's machinability is very good (72/100, better than 80% of aluminum grades); weldability poor (22/100); formability poor (28/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the aluminum family
Yield strength against density for every aluminum grade FabDigit runs. 2218 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 2218
Is 2218 easy to machine?
Machines well in T61/T72 with sharp carbide tools and flood coolant, but Ni/Fe intermetallics are abrasive — expect faster edge wear than 6061; chips break cleanly at moderate feeds.
Can 2218 be welded?
Not recommended for fusion welding (hot-cracking of the Al-Cu-Ni system); join by mechanical fasteners or resistance/friction-stir methods with qualified procedures.
Can 2218 be formed, bent or molded?
A forging alloy — hot forge/upset around 400–455 °C; cold forming in aged tempers is very limited, form only in F or freshly solution-treated condition.
Manufacturability
The process limits FabDigit applies to 2218. Every 2218 part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
CNC machining
| Machinability | Good72 / 100 |
|---|---|
| ISO material group | N.1 |
| Cutting speed (rough / finish) | 350 / 420 m/min |
| Minimum wall | 0.5 mm |
| Minimum internal radius | 1 mm |
| Drill depth limit | 8× diameter |
| Best surface (machined / polished) | Ra 0.8 / — |
| Hardenable after machining | No |
Sheet metal
| Formability | Fair28 / 100 |
|---|---|
| Weldability | Poor22 / 100 |
2218 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 | ≤ 0.9 | 0.4 |
| Feforms Al-Fe-Ni intermetallics that give hot strength | ≤ 1 | 0.6 |
| Cu | 3.5 – 4.5 | 4 |
| Mn | ≤ 0.2 | 0.05 |
| Mg | 1.2 – 1.8 | 1.5 |
| Cr | ≤ 0.1 | |
| Nikey elevated-temperature addition | 1.7 – 2.3 | 2 |
| Zn | ≤ 0.25 | |
| Others (each) | ≤ 0.05 | |
| Others (total) | ≤ 0.15 | |
| Al | balance |
What surface finishes work on 2218?
Hard anodize or chromate/organic coating for corrosion and wear protection; decorative anodizing yields a dull grey-brown tone, and polishing reveals coarse intermetallic streaks.
Surface treatments FabDigit runs on aluminum parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Passivation
Conversion Coating
PVD Coating
Equivalent designations
Standards and trade names that resolve to Aluminum 2218 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- A92218
- Aluminum Association
- AA2218
- EN / DIN / Werkstoff-Nr.
- AW-2218AW 2218
How much does 2218 cost?
2218 is a premium-cost aluminum ($$$), cheaper than about 59% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
2218 — frequently asked
What is 2218 used for?
2218 is typically used for forged engine pistons, cylinder heads, turbocharger impellers, jet-engine rings, high-temperature forged brackets and hot-end machined engine hardware. In short: engine pistons; heat-resistant.
What is the yield strength of 2218?
2218 has a typical yield strength of 305 MPa (44.2 ksi) and a tensile strength of 405 MPa (58.7 ksi) — stronger than 77% of aluminum grades. Strength varies by condition: see the 4 listed tempers.
Is 2218 easy to machine?
Yes — machinability is rated very good (72/100, better than 80% of aluminum grades). Machines well in T61/T72 with sharp carbide tools and flood coolant, but Ni/Fe intermetallics are abrasive — expect faster edge wear than 6061; chips break cleanly at moderate feeds.
Can 2218 be welded?
Not readily — weldability is rated poor (22/100). Not recommended for fusion welding (hot-cracking of the Al-Cu-Ni system); join by mechanical fasteners or resistance/friction-stir methods with qualified procedures.
What surface finishes work on 2218?
Hard anodize or chromate/organic coating for corrosion and wear protection; decorative anodizing yields a dull grey-brown tone, and polishing reveals coarse intermetallic streaks.
Can 2218 be formed, bent or molded?
A forging alloy — hot forge/upset around 400–455 °C; cold forming in aged tempers is very limited, form only in F or freshly solution-treated condition.
What is the maximum service temperature of 2218?
2218 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 2218-T61 and 2218-T72?
T61 is the default condition — standard high-strength temper for 2218 pistons and engine forgings; mild quench limits distortion and residual stress. T72: choose for pistons and hot-running parts where growth-free dimensional stability above 200 °C matters more than peak strength. Yield strength is 305 MPa in T61 versus 255 MPa in T72.
How much does 2218 cost?
2218 is a premium-cost aluminum ($$$), cheaper than about 59% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Can FabDigit make parts in 2218?
Yes — 2218 is available for CNC machining and sheet metal; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
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: Properties and Physical Metallurgy — ASM International (1984)
- EN 573-3 Aluminium and aluminium alloys — Chemical composition — CEN (2019)
- Aluminium alloy property tables (2000-series elevated-temperature forging alloys) — MatWeb / ASM Alloy Center (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.