Aluminum 224.0-T7
Temper
AA 224.0
T7 = solution heat treated and overaged (stabilized)
Choose for sand-cast high-strength structural parts where dimensional stability and reduced SCC sensitivity matter more than peak strength.
Values for the T7 condition
Other 224.0 tempers and conditions
224.0 is listed in 2 conditions; see the grade overview at 224.0.
- T7
- T72
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
T7This page Solution heat treated and overaged (stabilized) | Choose for sand-cast high-strength structural parts where dimensional stability and reduced SCC sensitivity matter more than peak strength. | 270 | 350 | 6 | 112 HB | 38 % IACS |
T72Default Solution heat treated and overaged to a controlled (stabilized)… | Standard commercial condition for 224.0 permanent-mold castings — best combination of strength, ductility and stability; the temper most data are published for. | 275 | 380 | 10 | 123 HB | 38 % IACS |
What is 224.0-T7?
224.0-T7 is 224.0 in the T7 temper — choose for sand-cast high-strength structural parts where dimensional stability and reduced SCC sensitivity matter more than peak strength. 224.0-T7 has a yield strength of 270 MPa (39.2 ksi) and a tensile strength of 350 MPa (50.8 ksi) — stronger than 69% of aluminum grades. Elongation at break is 6% and the elastic modulus is 71 GPa (10.3 Msi). 224.0-T7 has a density of 2.81 g/cm³ (0.102 lb/in³), heavier than 86% of aluminum grades. It melts at 570°C (1,058 °F). T72 is the default condition FabDigit quotes; T7 is available on request or by drawing note.
Advantages
- Easy to machine — 78/100, better than 89% of aluminum grades
- High service temperature — 175°C (347 °F), better than 83% of aluminum grades
Limitations
- Needs corrosion protection — 36/100, worse than 81% of aluminum grades
- Difficult to weld — 25/100, worse than 76% of aluminum grades
224.0-T7 properties
Typical room-temperature values for 224.0-T7; 14 are specific to this condition. Other listed values are 224.0 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
224.0-T7 has a density of 2.81 g/cm³ (0.102 lb/in³), heavier than 86% of aluminum grades. It melts at 570°C (1,058 °F).
Mechanical12
224.0-T7 has a yield strength of 270 MPa (39.2 ksi) and a tensile strength of 350 MPa (50.8 ksi) — stronger than 69% of aluminum grades. Elongation at break is 6% and the elastic modulus is 71 GPa (10.3 Msi).
Thermal6
224.0-T7 is rated for continuous service to 175°C (347 °F). It conducts heat at 130 W/m·K (75.1 BTU/hr·ft·°F), worse than 65% of aluminum grades. Thermal expansion is 22.5 µm/m·K (12.5 µin/in·°F).
Electrical3
224.0-T7 conducts electricity at 38 % IACS, better than 61% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (36/100), worse than 81% of aluminum grades.
Sustainability4
Producing a kilogram of 224.0-T7 takes about 205 MJ of energy and emits 12.5 kg of CO₂ — more than 76% of aluminum grades. Typical recycled content is 15%.
Manufacturability7
224.0-T7's machinability is very good (78/100, better than 89% of aluminum grades); weldability poor (25/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 224.0-T7
Is 224.0 easy to machine?
Machines very well in T7/T72 with sharp PCD or polished carbide tooling, high speed and light feed; chips are short and finishes are excellent, but watch for porosity exposure on sealing faces.
Can 224.0 be welded?
Essentially not weldable by fusion processes — high Cu content makes it severely hot-crack sensitive; weld repair generally prohibited on aerospace castings, use mechanical fastening or adhesive joining.
Can 224.0 be formed, bent or molded?
Foundry-critical alloy: needs high-purity charge, degassing, grain refinement, chills and generous risering to avoid hot tearing and shrinkage; permanent-mold and controlled sand practice with HIP is common for premium castings.
What surface finishes work on 224.0?
Prefer chromate-free conversion coating plus primer/topcoat or hard anodize for wear; standard sulfuric anodize gives dark, uneven color due to Cu, and bare surfaces need protection in humid or chloride environments.
224.0 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 |
|---|---|---|
| Cuprincipal strengthening element | 4.5 – 5.5 | 5 |
| Mn | 0.2 – 0.5 | 0.35 |
| Simax — high-purity base required | ≤ 0.06 | — |
| Fe | ≤ 0.1 | — |
| Mg | ≤ 0.03 | — |
| Zn | ≤ 0.1 | — |
| Tigrain refinement; verify limits against current AA Teal Sheets | 0.1 – 0.35 | 0.2 |
| Vdispersoid former for elevated-temperature stability | 0.05 – 0.15 | 0.1 |
| Zrdispersoid former; verify against current AA Teal Sheets | 0.1 – 0.25 | 0.18 |
| Others (each) | ≤ 0.03 | — |
| Others (total) | ≤ 0.1 | — |
| Al | balance | — |
224.0-T7 — frequently asked
What is 224.0-T7 used for?
224.0-T7 is typically used for aerospace structural castings, airframe fittings and load-bearing brackets, fatigue-loaded machinery castings, gearbox and pump housings needing high strength, ordnance and missile component housings and HIP-treated high-integrity sand castings. In short: highest-strength cast aluminum; aerospace Al-Cu casting alloy; strong but non-weldable.
What is the yield strength of 224.0-T7?
224.0-T7 has a typical yield strength of 270 MPa (39.2 ksi) and a tensile strength of 350 MPa (50.8 ksi) — stronger than 69% of aluminum grades. Strength varies by condition: see the 2 listed tempers.
Is 224.0-T7 easy to machine?
Yes — machinability is rated very good (78/100, better than 89% of aluminum grades). Machines very well in T7/T72 with sharp PCD or polished carbide tooling, high speed and light feed; chips are short and finishes are excellent, but watch for porosity exposure on sealing faces.
Can 224.0-T7 be welded?
Not readily — weldability is rated poor (25/100). Essentially not weldable by fusion processes — high Cu content makes it severely hot-crack sensitive; weld repair generally prohibited on aerospace castings, use mechanical fastening or adhesive joining.
What surface finishes work on 224.0-T7?
Prefer chromate-free conversion coating plus primer/topcoat or hard anodize for wear; standard sulfuric anodize gives dark, uneven color due to Cu, and bare surfaces need protection in humid or chloride environments.
Can 224.0-T7 be formed, bent or molded?
Foundry-critical alloy: needs high-purity charge, degassing, grain refinement, chills and generous risering to avoid hot tearing and shrinkage; permanent-mold and controlled sand practice with HIP is common for premium castings.
What is the maximum service temperature of 224.0-T7?
224.0-T7 is rated for continuous use to about 175°C (347 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 224.0-T72 and 224.0-T7?
T72 is the default condition — standard commercial condition for 224.0 permanent-mold castings — best combination of strength, ductility and stability; the temper most data are published for. T7: choose for sand-cast high-strength structural parts where dimensional stability and reduced SCC sensitivity matter more than peak strength. Yield strength is 275 MPa in T72 versus 270 MPa in T7.
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)
- ASM Specialty Handbook: Aluminum and Aluminum Alloys — ASM International (1993)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
- ASTM B26/B26M — Aluminum-Alloy Sand Castings; ASTM B108/B108M — Aluminum-Alloy Permanent Mold Castings — ASTM International (2022)
- ASM Handbook Vol.13B — Corrosion: Materials — ASM International (2005)
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.