Aluminum EN AC-48000-T6
Temper · default condition
EN AC-48000 · JIS AC8A · GB ZL109
T6 = solution heat treated and artificially aged
Default condition for highly loaded diesel and turbo-petrol pistons where maximum room- and elevated-temperature strength is required.
Values for the T6 condition
Other EN AC-48000 tempers and conditions
EN AC-48000 is listed in 4 conditions; see the grade overview at EN AC-48000.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As fabricated | Cheapest condition for non-critical or low-load castings that will not see high thermal loading. | 130 | 180 | 1.5 | 85 HB | 29 % IACS |
Cooled from hot working and artificially aged | Pick when dimensional stability and low distortion matter more than peak strength — no quench, so pistons keep tight tolerances. | 190 | 215 | 1 | 100 HB | 35 % IACS |
Solution heat treated and overaged (stabilized) | Choose for parts running continuously above ~230 °C where thermal growth and hardness drop in service must be avoided; trades ~10–15% strength for stability. | 215 | 250 | 1.2 | 105 HB | 28 % IACS |
T6DefaultThis page Solution heat treated and artificially aged | Default condition for highly loaded diesel and turbo-petrol pistons where maximum room- and elevated-temperature strength is required. | 255 | 295 | 1 | 115 HB | 33 % IACS |
What is EN AC-48000-T6?
EN AC-48000-T6 is EN AC-48000 in the T6 temper — default condition for highly loaded diesel and turbo-petrol pistons where maximum room- and elevated-temperature strength is required. EN AC-48000-T6 has a yield strength of 255 MPa (37 ksi) and a tensile strength of 295 MPa (42.8 ksi) — stronger than 67% of aluminum grades. Elongation at break is 1% and the elastic modulus is 82 GPa (11.9 Msi). EN AC-48000-T6 has a density of 2.7 g/cm³ (0.0975 lb/in³), lighter than 59% of aluminum grades. It melts at 510°C (950 °F).
Advantages
- Stiff — 82 GPa (11.9 Msi), better than 97% of aluminum grades
- High service temperature — 250°C (482 °F), better than 97% of aluminum grades
Limitations
- Low fracture toughness — 14 MPa·√m (12.7 ksi·√in), worse than 97% of aluminum grades
- Limited ductility — 1%, worse than 95% of aluminum grades
- Limited formability — 5/100, worse than 94% of aluminum grades
- Hard to polish — 40/100, worse than 91% of aluminum grades
- Difficult to weld — 25/100, worse than 76% of aluminum grades
EN AC-48000-T6 properties
Typical room-temperature values for EN AC-48000-T6; 40 are specific to this condition. Other listed values are EN AC-48000 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
EN AC-48000-T6 has a density of 2.7 g/cm³ (0.0975 lb/in³), lighter than 59% of aluminum grades. It melts at 510°C (950 °F).
Mechanical14
EN AC-48000-T6 has a yield strength of 255 MPa (37 ksi) and a tensile strength of 295 MPa (42.8 ksi) — stronger than 67% of aluminum grades. Elongation at break is 1% and the elastic modulus is 82 GPa (11.9 Msi).
Thermal6
EN AC-48000-T6 is rated for continuous service to 250°C (482 °F). It conducts heat at 135 W/m·K (78 BTU/hr·ft·°F), worse than 58% of aluminum grades. Thermal expansion is 19.5 µm/m·K (10.8 µin/in·°F).
Electrical3
EN AC-48000-T6 conducts electricity at 33 % IACS, worse than 57% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (42/100), worse than 69% of aluminum grades.
Sustainability4
Producing a kilogram of EN AC-48000-T6 takes about 205 MJ of energy and emits 12.5 kg of CO₂ — more than 76% of aluminum grades. Typical recycled content is 65%.
Manufacturability8
EN AC-48000-T6's machinability is fair (48/100, worse than 68% of aluminum grades); weldability poor (25/100); formability not recommended (5/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with EN AC-48000-T6
Is EN AC-48000 easy to machine?
Use PCD or fine-grain carbide with high speed and light feed — the eutectic/primary silicon is highly abrasive; chips are short and coolant-friendly, and ring grooves are typically finish-turned after ageing.
Can EN AC-48000 be welded?
Effectively non-weldable for structural repair: Cu+Mg cause hot cracking and the low solidus limits heat input; friction-stir or laser repair with 4047 filler only under qualified procedures.
Can EN AC-48000 be formed, bent or molded?
Excellent gravity-die, squeeze and low-pressure casting fluidity; use Sr/Na modification plus P for primary Si control, controlled die temperature and directional solidification to avoid shrinkage porosity in the crown.
What surface finishes work on EN AC-48000?
Hard anodizing of crown and top ring groove or ferrous ring-carrier insertion is common; decorative anodizing is grey and blotchy because of the silicon, so shot blast, tin/graphite skirt coatings or phosphate are preferred.
EN AC-48000 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 |
|---|---|---|
| Sinear-eutectic; modified/refined for fine eutectic structure | 10.5 – 13.5 | 12 |
| Cu | 0.8 – 1.5 | 1.1 |
| MgMg2Si precipitation hardening | 0.8 – 1.5 | 1.1 |
| Niforms thermally stable aluminides for hot strength | 0.7 – 1.3 | 1 |
| Feimpurity limit | ≤ 0.7 | 0.4 |
| Mn | ≤ 0.35 | 0.15 |
| Zn | ≤ 0.35 | 0.1 |
| Tigrain refinement | ≤ 0.25 | 0.1 |
| Pb | ≤ 0.1 | — |
| Sn | ≤ 0.05 | — |
| Others (each)total 0.15 max | ≤ 0.05 | — |
| Al | balance | — |
EN AC-48000-T6 — frequently asked
What is EN AC-48000-T6 used for?
EN AC-48000-T6 is typically used for pistons, engine components and high-temperature parts. In short: standard piston casting alloy; low expansion, 250 °C capable; hardest of the Al-Si12 group.
What is the yield strength of EN AC-48000-T6?
EN AC-48000-T6 has a typical yield strength of 255 MPa (37 ksi) and a tensile strength of 295 MPa (42.8 ksi) — stronger than 67% of aluminum grades. Strength varies by condition: see the 4 listed tempers.
Is EN AC-48000-T6 easy to machine?
Reasonably — machinability is rated fair (48/100, worse than 68% of aluminum grades). Use PCD or fine-grain carbide with high speed and light feed — the eutectic/primary silicon is highly abrasive; chips are short and coolant-friendly, and ring grooves are typically finish-turned after ageing.
Can EN AC-48000-T6 be welded?
Not readily — weldability is rated poor (25/100). Effectively non-weldable for structural repair: Cu+Mg cause hot cracking and the low solidus limits heat input; friction-stir or laser repair with 4047 filler only under qualified procedures.
What surface finishes work on EN AC-48000-T6?
Hard anodizing of crown and top ring groove or ferrous ring-carrier insertion is common; decorative anodizing is grey and blotchy because of the silicon, so shot blast, tin/graphite skirt coatings or phosphate are preferred.
Can EN AC-48000-T6 be formed, bent or molded?
Excellent gravity-die, squeeze and low-pressure casting fluidity; use Sr/Na modification plus P for primary Si control, controlled die temperature and directional solidification to avoid shrinkage porosity in the crown.
What is the maximum service temperature of EN AC-48000-T6?
EN AC-48000-T6 is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between EN AC-48000-T6 and EN AC-48000-F?
T6 is the default condition — default condition for highly loaded diesel and turbo-petrol pistons where maximum room- and elevated-temperature strength is required. F: cheapest condition for non-critical or low-load castings that will not see high thermal loading. Yield strength is 255 MPa in T6 versus 130 MPa in F.
Sources
- EN 1706 — Aluminium and aluminium alloys: castings, chemical composition and mechanical properties — CEN (2020)
- GB/T 1173 (ZL109) — SAC (2013)
- JIS H 5202 Aluminium alloy castings (AC8A) — JSA (2010)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys (332.0/A332.0 piston alloys) — ASM International (1990)
- ASM Handbook Vol. 15 — Casting — ASM International (2008)
- Piston alloy datasheets (Al-Si12CuNiMg / AC8A class) — Foundry & piston producers (2022)
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.