Aluminum 712-T6
Temper
AA 712 · UNS A07120 · EN AlZn5Mg · also ZG61A
T6 = solution heat treated and artificially aged
Rarely supplied — 712.0 is specified as a self-aging alloy, so full solution treatment plus quench is normally avoided because it removes the alloy's main advantage and risks distortion; use only against a customer-specific spec with qualification testing.
Values for the T6 condition
Other 712 tempers and conditions
712 is listed in 4 conditions; see the grade overview at 712.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Cooled from hot working and naturally aged | Self-aging Al-Zn-Mg sand casting alloy 712.0 in the as-cast, naturally aged T1 condition — develops near-T5 strength without solution treatment, with good machinability and dimensional stability. | 170 | 240 | 4 | 75 HB | 35 % IACS |
As fabricated | Standard supply condition: strength develops by self-aging over ~2–4 weeks at room temperature, no solution treatment or quench needed. | 172 | 240 | 5 | 75 HB | 40 % IACS |
Cooled from hot working and artificially aged | Choose when the natural-aging waiting period is unacceptable or dimensional stability before machining is required; a short low-temperature age gives essentially the naturally aged property level. | 175 | 240 | 4 | 78 HB | 39 % IACS |
T6This page Solution heat treated and artificially aged | Rarely supplied — 712.0 is specified as a self-aging alloy, so full solution treatment plus quench is normally avoided because it removes the alloy's main advantage and risks distortion; use only against a customer-specific spec with qualification testing. | 215 | 275 | 3 | 90 HB | 38 % IACS |
What is 712-T6?
712-T6 is 712 in the T6 temper — rarely supplied — 712.0 is specified as a self-aging alloy, so full solution treatment plus quench is normally avoided because it removes the alloy's main advantage and risks distortion; use only against a customer-specific spec with qualification testing. 712-T6 has a yield strength of 215 MPa (31.2 ksi) and a tensile strength of 275 MPa (39.9 ksi) — stronger than 58% of aluminum grades. Elongation at break is 3% and the elastic modulus is 71 GPa (10.3 Msi). 712-T6 has a density of 2.81 g/cm³ (0.102 lb/in³), heavier than 86% of aluminum grades. It melts at 600°C (1,112 °F).
Advantages
- Easy to machine — 75/100, better than 86% of aluminum grades
Limitations
- Limited ductility — 3%, worse than 79% of aluminum grades
712-T6 properties
Typical room-temperature values for 712-T6; 21 are specific to this condition. Other listed values are 712 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
712-T6 has a density of 2.81 g/cm³ (0.102 lb/in³), heavier than 86% of aluminum grades. It melts at 600°C (1,112 °F).
Mechanical10
712-T6 has a yield strength of 215 MPa (31.2 ksi) and a tensile strength of 275 MPa (39.9 ksi) — stronger than 58% of aluminum grades. Elongation at break is 3% and the elastic modulus is 71 GPa (10.3 Msi).
Thermal6
712-T6 is rated for continuous service to 150°C (302 °F). It conducts heat at 152 W/m·K (87.8 BTU/hr·ft·°F), better than 66% of aluminum grades. Thermal expansion is 23.6 µm/m·K (13.1 µin/in·°F).
Electrical3
712-T6 conducts electricity at 38 % IACS, better than 61% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (54/100), worse than 55% of aluminum grades.
Sustainability4
Producing a kilogram of 712-T6 takes about 195 MJ of energy and emits 12 kg of CO₂ — less than 86% of aluminum grades. Typical recycled content is 50%.
Manufacturability6
712-T6's machinability is very good (75/100, better than 86% of aluminum grades); weldability good (55/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 712-T6
Is 712 easy to machine?
Machines well with sharp carbide or PCD tooling, high speed and light feed; free-flowing chips, good surface finish, and it holds size well because no quench stresses are present.
Can 712 be welded?
Fair-to-good with GTAW/GMAW using 5356 or 5183 filler; the Zn–Mg matrix re-ages naturally so strength recovers near the weld, but keep heat input low to limit hot cracking and porosity.
Can 712 be formed, bent or molded?
Sand casting is the practical route — fluidity is only moderate and the alloy is hot-tear sensitive, so use generous fillets, directional solidification and chills; avoid permanent-mould/die casting.
What surface finishes work on 712?
Anodizes well (clear or hard coat) and takes chromate/conversion coatings and paint; polish to a moderate lustre only, since sand-cast porosity limits mirror finishes.
712 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 | ≤ 0.3 | — |
| Fe | ≤ 0.5 | — |
| Cu | ≤ 0.25 | — |
| Mn | ≤ 0.1 | — |
| Mg | 0.5 – 0.65 | 0.58 |
| Cr | 0.4 – 0.6 | 0.5 |
| Zn | 5 – 6.5 | 5.8 |
| Tigrain refiner | 0.15 – 0.25 | 0.2 |
| Others (each)0.20 total max | ≤ 0.05 | — |
| Al | balance | — |
712-T6 — frequently asked
What is 712-T6 used for?
712-T6 is typically used for decorative castings, hardware and light brackets. In short: cast Al-Zn-Mg.
What is the yield strength of 712-T6?
712-T6 has a typical yield strength of 215 MPa (31.2 ksi) and a tensile strength of 275 MPa (39.9 ksi) — stronger than 58% of aluminum grades. Strength varies by condition: see the 4 listed tempers.
Is 712-T6 easy to machine?
Yes — machinability is rated very good (75/100, better than 86% of aluminum grades). Machines well with sharp carbide or PCD tooling, high speed and light feed; free-flowing chips, good surface finish, and it holds size well because no quench stresses are present.
Can 712-T6 be welded?
Yes — weldability is rated good (55/100). Fair-to-good with GTAW/GMAW using 5356 or 5183 filler; the Zn–Mg matrix re-ages naturally so strength recovers near the weld, but keep heat input low to limit hot cracking and porosity.
What surface finishes work on 712-T6?
Anodizes well (clear or hard coat) and takes chromate/conversion coatings and paint; polish to a moderate lustre only, since sand-cast porosity limits mirror finishes.
Can 712-T6 be formed, bent or molded?
Sand casting is the practical route — fluidity is only moderate and the alloy is hot-tear sensitive, so use generous fillets, directional solidification and chills; avoid permanent-mould/die casting.
What is the maximum service temperature of 712-T6?
712-T6 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 712-T6?
Yes — 712-T6 is available for CNC machining; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- Designations and Chemical Composition Limits for Aluminum Alloys in the Form of Castings and Ingot (Pink Sheets) — The Aluminum Association (2018)
- ASTM B26/B26M — Aluminum-Alloy Sand Castings — ASTM (2018)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Specialty Handbook: Aluminum and Aluminum Alloys — ASM International (1993)
- ASM Handbook Vol.15 — Casting — ASM International (2008)
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.