Aluminum ZL105A-T7
Temper
ASTM A355.0
T7 = solution heat treated and overaged (stabilized)
Choose for dimensional stability and reduced residual stress at elevated service temperature, accepting lower strength.
Values for the T7 condition
Other ZL105A tempers and conditions
ZL105A is listed in 7 conditions; see the grade overview at ZL105A.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As fabricated | Lowest cost condition for lightly loaded or dimensionally sensitive parts where no heat-treat distortion is acceptable. | 90 | 165 | 2 | 65 HB | 42 % IACS |
Cooled from hot working and naturally aged | Simple aging of the as-cast part for a modest strength gain without solution treatment or quench distortion. | 135 | 205 | 1.5 | 72 HB | 41 % IACS |
T7This page Solution heat treated and overaged (stabilized) | Choose for dimensional stability and reduced residual stress at elevated service temperature, accepting lower strength. | 200 | 250 | 4 | 78 HB | 42 % IACS |
T6Default Solution heat treated and artificially aged | The default general-purpose condition — best balance of strength, hardness and ductility for structural castings (equivalent to C355.0-T6). | 225 | 290 | 3 | 88 HB | 39 % IACS |
Cooled from hot working and artificially aged | The condition specified in GB/T 1173 for ZL105A — highest guaranteed strength for Chinese-standard castings. | 225 | 290 | 2 | 85 HB | 40 % IACS |
T6 variant, underaged | Pick when peak strength is needed from chill-cast or premium-quality castings and some ductility can be traded away. | 250 | 310 | 3 | 95 HB | 39 % IACS |
T6, heat treated by the user | Aerospace premium-quality practice giving the highest guaranteed properties from well-fed, low-porosity castings. | 270 | 315 | 2.5 | 100 HB | 38 % IACS |
What is ZL105A-T7?
ZL105A-T7 is ZL105A in the T7 temper — choose for dimensional stability and reduced residual stress at elevated service temperature, accepting lower strength. ZL105A-T7 has a yield strength of 200 MPa (29 ksi) and a tensile strength of 250 MPa (36.3 ksi) — stronger than 53% of aluminum grades. Elongation at break is 4% and the elastic modulus is 71 GPa (10.3 Msi). ZL105A-T7 has a density of 2.71 g/cm³ (0.0979 lb/in³), heavier than 51% of aluminum grades. It melts at 546°C (1,015 °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
- High electrical conductivity — 42 % IACS, better than 81% of aluminum grades
- Tough — resists crack growth — 31 MPa·√m (28.2 ksi·√in), better than 80% of aluminum grades
ZL105A-T7 properties
Typical room-temperature values for ZL105A-T7; 19 are specific to this condition. Other listed values are ZL105A reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
ZL105A-T7 has a density of 2.71 g/cm³ (0.0979 lb/in³), heavier than 51% of aluminum grades. It melts at 546°C (1,015 °F).
Mechanical12
ZL105A-T7 has a yield strength of 200 MPa (29 ksi) and a tensile strength of 250 MPa (36.3 ksi) — stronger than 53% of aluminum grades. Elongation at break is 4% and the elastic modulus is 71 GPa (10.3 Msi).
Thermal6
ZL105A-T7 is rated for continuous service to 200°C (392 °F). It conducts heat at 159 W/m·K (91.9 BTU/hr·ft·°F), better than 74% of aluminum grades. Thermal expansion is 22.3 µm/m·K (12.4 µin/in·°F).
Electrical3
ZL105A-T7 conducts electricity at 42 % IACS, better than 81% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (48/100), worse than 58% of aluminum grades.
Sustainability4
Producing a kilogram of ZL105A-T7 takes about 200 MJ of energy and emits 12.5 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 35%.
Manufacturability7
ZL105A-T7's machinability is very good (70/100, better than 72% 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 ZL105A-T7
Is ZL105A easy to machine?
Machines well with PCD or polished carbide, high speed and low feed; eutectic silicon is abrasive, so use flood coolant and expect tool wear higher than 6061.
Can ZL105A be welded?
TIG/MIG repairable with ER4043 or ER4145 filler; the Cu content raises hot-cracking risk and welded areas should be re-solution treated and aged to restore T6 properties.
Can ZL105A be formed, bent or molded?
Excellent fluidity and pressure tightness in sand, permanent-mold and low-pressure casting; use chills and good risering, Sr/Na modification and Ti-B grain refinement, and control hydrogen to avoid porosity.
What surface finishes work on ZL105A?
Takes protective sulphuric or hard anodize (dark grey, non-decorative), chromate/trivalent conversion coating, and powder or wet paint; shot-peening improves fatigue on machined surfaces.
ZL105A 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 |
|---|---|---|
| SiGB/T 1173 ZAlSi5Cu1MgA | 4.5 – 5.5 | 5 |
| Cu | 1 – 1.5 | 1.25 |
| Mgnarrower than ZL105 (0.4–0.6) | 0.4 – 0.55 | 0.48 |
| Feimpurity limit, high-purity grade | ≤ 0.2 | — |
| Mnimpurity | ≤ 0.1 | — |
| Tiimpurity / grain refiner residue | ≤ 0.15 | — |
| Znimpurity | ≤ 0.1 | — |
| others eachimpurity | ≤ 0.05 | — |
| others totalimpurity total | ≤ 0.5 | — |
| Al | balance | — |
ZL105A-T7 — frequently asked
What is ZL105A-T7 used for?
ZL105A-T7 is typically used for aerospace fittings, high-strength pump castings, gearbox and transmission housings, hydraulic valve bodies, airframe brackets and compressor housings. In short: high-purity ZL105 upgrade; best machinability in the family; aerospace-grade cleanliness.
What is the yield strength of ZL105A-T7?
ZL105A-T7 has a typical yield strength of 200 MPa (29 ksi) and a tensile strength of 250 MPa (36.3 ksi) — stronger than 53% of aluminum grades. Strength varies by condition: see the 7 listed tempers.
Is ZL105A-T7 easy to machine?
Yes — machinability is rated very good (70/100, better than 72% of aluminum grades). Machines well with PCD or polished carbide, high speed and low feed; eutectic silicon is abrasive, so use flood coolant and expect tool wear higher than 6061.
Can ZL105A-T7 be welded?
Yes — weldability is rated good (55/100). TIG/MIG repairable with ER4043 or ER4145 filler; the Cu content raises hot-cracking risk and welded areas should be re-solution treated and aged to restore T6 properties.
What surface finishes work on ZL105A-T7?
Takes protective sulphuric or hard anodize (dark grey, non-decorative), chromate/trivalent conversion coating, and powder or wet paint; shot-peening improves fatigue on machined surfaces.
Can ZL105A-T7 be formed, bent or molded?
Excellent fluidity and pressure tightness in sand, permanent-mold and low-pressure casting; use chills and good risering, Sr/Na modification and Ti-B grain refinement, and control hydrogen to avoid porosity.
What is the maximum service temperature of ZL105A-T7?
ZL105A-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 ZL105A-T6 and ZL105A-F?
T6 is the default condition — the default general-purpose condition — best balance of strength, hardness and ductility for structural castings (equivalent to C355.0-T6). F: lowest cost condition for lightly loaded or dimensionally sensitive parts where no heat-treat distortion is acceptable. Yield strength is 225 MPa in T6 versus 90 MPa in F.
Sources
- ASTM B26/B26M and B108/B108M (355.0, C355.0 castings) — ASTM International (2022)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol.15 — Casting — ASM International (2008)
- Aluminum Association Registration Record (Pink Sheets) — cast alloy limits — The Aluminum Association (2018)
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.