Aluminum 358.0-T7
Temper
AA 358.0
T7 = solution heat treated and overaged (stabilized)
Overaged for dimensional stability and lower residual stress where elevated-temperature service or machining stability governs.
Values for the T7 condition
Other 358.0 tempers and conditions
358.0 is listed in 6 conditions; see the grade overview at 358.0.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As fabricated | Untreated castings used only as an intermediate state before solution treatment, or for non-structural parts. | 95 | 180 | 6 | 55 HB | 41 % IACS |
Cooled from hot working and artificially aged | Low-cost partial strengthening with no solution treatment; used when distortion from quenching must be avoided. | 150 | 205 | 3 | 70 HB | 42 % IACS |
T7This page Solution heat treated and overaged (stabilized) | Overaged for dimensional stability and lower residual stress where elevated-temperature service or machining stability governs. | 220 | 275 | 6 | 85 HB | 42 % IACS |
T6 variant, underaged | Underaged/controlled-age variant chosen when higher elongation and toughness matter more than peak yield strength. | 250 | 320 | 8 | 90 HB | 39 % IACS |
T6Default Solution heat treated and artificially aged | Standard supply condition: best balance of strength and ductility for structural sand, permanent-mold and investment castings. | 275 | 345 | 5 | 100 HB | 39 % IACS |
T6, heat treated by the user | Peak-aged condition for maximum strength in aerospace and highly loaded castings, at the cost of ductility and toughness. | 290 | 379 | 5 | 110 HB | 38 % IACS |
What is 358.0-T7?
358.0-T7 is 358.0 in the T7 temper — overaged for dimensional stability and lower residual stress where elevated-temperature service or machining stability governs. 358.0-T7 has a yield strength of 220 MPa (31.9 ksi) and a tensile strength of 275 MPa (39.9 ksi) — stronger than 59% of aluminum grades. Elongation at break is 6% and the elastic modulus is 72 GPa (10.4 Msi). 358.0-T7 has a density of 2.68 g/cm³ (0.0968 lb/in³), lighter than 72% of aluminum grades. It melts at 557°C (1,035 °F). T6 is the default condition FabDigit quotes; T7 is available on request or by drawing note.
Advantages
- High service temperature — 200°C (392 °F), better than 90% of aluminum grades
- Tough — resists crack growth — 32 MPa·√m (29.1 ksi·√in), better than 83% of aluminum grades
- High electrical conductivity — 42 % IACS, better than 81% of aluminum grades
Limitations
- Limited formability — 8/100, worse than 88% of aluminum grades
358.0-T7 properties
Typical room-temperature values for 358.0-T7; 22 are specific to this condition. Other listed values are 358.0 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
358.0-T7 has a density of 2.68 g/cm³ (0.0968 lb/in³), lighter than 72% of aluminum grades. It melts at 557°C (1,035 °F).
Mechanical11
358.0-T7 has a yield strength of 220 MPa (31.9 ksi) and a tensile strength of 275 MPa (39.9 ksi) — stronger than 59% of aluminum grades. Elongation at break is 6% and the elastic modulus is 72 GPa (10.4 Msi).
Thermal6
358.0-T7 is rated for continuous service to 200°C (392 °F). It conducts heat at 158 W/m·K (91.3 BTU/hr·ft·°F), better than 74% of aluminum grades. Thermal expansion is 21.5 µm/m·K (11.9 µin/in·°F).
Electrical3
358.0-T7 conducts electricity at 42 % IACS, better than 81% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (60/100), better than 62% of aluminum grades.
Sustainability4
Producing a kilogram of 358.0-T7 takes about 200 MJ of energy and emits 12.5 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 15%.
Manufacturability8
358.0-T7's machinability is good (58/100, worse than 54% of aluminum grades); weldability very good (70/100); formability not recommended (8/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 358.0-T7
Is 358.0 easy to machine?
Machines well with sharp PCD or polished carbide tooling, high speed and flood coolant; the hard eutectic Si is abrasive so HSS tool life is short.
Can 358.0 be welded?
GTAW/GMAW with 4043 or 4047 filler is routine for repair, but the joint must be re-solution treated and aged to recover T6 properties; beryllium fume extraction is mandatory.
Can 358.0 be formed, bent or molded?
A casting alloy only — excellent fluidity and pressure tightness in sand, permanent-mold and investment casting; use chills and directional solidification, HIP for aerospace class-A parts.
What surface finishes work on 358.0?
Takes sulfuric and hard-coat anodizing for protection (dark grey cosmetic due to Si), chromate/trivalent conversion coating and primer-paint systems; bright decorative anodizing is not practical.
358.0 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 | 7.6 – 8.6 | 8.1 |
| Mg | 0.4 – 0.6 | 0.5 |
| BeBeryllium addition — melting/welding fume requires dedicated extraction and PPE | 0.1 – 0.3 | 0.18 |
| Tigrain refinement | 0.1 – 0.2 | 0.15 |
| Feimpurity limit | ≤ 0.2 | — |
| Cuimpurity limit | ≤ 0.2 | — |
| Mnimpurity limit | ≤ 0.2 | — |
| Znimpurity limit | ≤ 0.1 | — |
| Others (each) | ≤ 0.05 | — |
| Others (total) | ≤ 0.15 | — |
| Al | balance | — |
358.0-T7 — frequently asked
What is 358.0-T7 used for?
358.0-T7 is typically used for general-purpose sand castings, permanent-mold pump and valve bodies, pressure-tight manifold and housing castings, aerospace brackets and fittings in T6, investment-cast structural components and gearbox cases and covers. In short: heat-treatable Al-Si-Mg casting alloy; good castability, moderate strength; beryllium-bearing; fume control needed.
What is the yield strength of 358.0-T7?
358.0-T7 has a typical yield strength of 220 MPa (31.9 ksi) and a tensile strength of 275 MPa (39.9 ksi) — stronger than 59% of aluminum grades. Strength varies by condition: see the 6 listed tempers.
Is 358.0-T7 easy to machine?
Reasonably — machinability is rated good (58/100, worse than 54% of aluminum grades). Machines well with sharp PCD or polished carbide tooling, high speed and flood coolant; the hard eutectic Si is abrasive so HSS tool life is short.
Can 358.0-T7 be welded?
Yes — weldability is rated very good (70/100). GTAW/GMAW with 4043 or 4047 filler is routine for repair, but the joint must be re-solution treated and aged to recover T6 properties; beryllium fume extraction is mandatory.
What surface finishes work on 358.0-T7?
Takes sulfuric and hard-coat anodizing for protection (dark grey cosmetic due to Si), chromate/trivalent conversion coating and primer-paint systems; bright decorative anodizing is not practical.
Can 358.0-T7 be formed, bent or molded?
A casting alloy only — excellent fluidity and pressure tightness in sand, permanent-mold and investment casting; use chills and directional solidification, HIP for aerospace class-A parts.
What is the maximum service temperature of 358.0-T7?
358.0-T7 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 358.0-T6 and 358.0-F?
T6 is the default condition — standard supply condition: best balance of strength and ductility for structural sand, permanent-mold and investment castings. F: untreated castings used only as an intermediate state before solution treatment, or for non-structural parts. Yield strength is 275 MPa in T6 versus 95 MPa in F.
Sources
- Registration Record of International Alloy Designations and Chemical Composition Limits for Aluminum Alloys in the Form of Castings and Ingot (Pink Sheets) — The Aluminum Association (2019)
- ASTM B26/B26M — Aluminum-Alloy Sand Castings — ASTM International (2018)
- ASTM B108/B108M — Aluminum-Alloy Permanent Mold Castings — ASTM International (2019)
- 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)
- ASM Handbook Vol. 19 — Fatigue and Fracture — ASM International (1996)
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.