A356/Al2O3/20p T7
Temper
also Duralcan W6A.20A
T7 = solution heat treated and overaged (stabilized)
Pick for dimensional stability and slightly better ductility/toughness at elevated service temperature, at some strength cost.
Values for the T7 condition
Other A356/Al2O3/20p grades and fills
A356/Al2O3/20p is listed in 4 conditions; see the grade overview at A356/Al2O3/20p.
Compare all 4 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
As fabricated | Lowest-cost condition for non-critical wear parts where stiffness and CTE, not strength, drive the design. | 125 | 190 | 1 | — |
Cooled from hot working and artificially aged | Choose when distortion from solution quenching must be avoided but some strengthening is needed. | 205 | 255 | 0.8 | — |
T7This page Solution heat treated and overaged (stabilized) | Pick for dimensional stability and slightly better ductility/toughness at elevated service temperature, at some strength cost. | 245 | 290 | 1.2 | — |
T6Default Solution heat treated and artificially aged | Standard delivery condition for structural and brake/piston applications: peak strength with maximum stiffness benefit from the alumina. | 290 | 330 | 0.7 | — |
What is A356/Al2O3/20p T7?
A356/Al2O3/20p T7 is A356/Al2O3/20p in the T7 temper — pick for dimensional stability and slightly better ductility/toughness at elevated service temperature, at some strength cost. A356/Al2O3/20p T7 has a yield strength of 245 MPa (35.5 ksi) and a tensile strength of 290 MPa (42.1 ksi) — weaker than 58% of composite grades. Elongation at break is 1.2% and the elastic modulus is 98 GPa (14.2 Msi). A356/Al2O3/20p T7 has a density of 2.94 g/cm³ (0.106 lb/in³), heavier than 91% of composite grades. T6 is the default condition FabDigit quotes; T7 is available on request or by drawing note.
Advantages
- Conducts heat well — 145 W/m·K (83.8 BTU/hr·ft·°F), better than 91% of composite grades
- Polishes to a fine finish — 55/100, better than 83% of composite grades
- Good UV / weathering resistance — 95/100, better than 78% of composite grades
Limitations
- Heavy — 2.94 g/cm³ (0.106 lb/in³), worse than 91% of composite grades
- Needs corrosion protection — 60/100, worse than 79% of composite grades
A356/Al2O3/20p T7 properties
Typical room-temperature values for A356/Al2O3/20p T7; 14 are specific to this condition. Other listed values are A356/Al2O3/20p reference data and may not represent this condition. Bars are the position among composite grades.
Physical1
A356/Al2O3/20p T7 has a density of 2.94 g/cm³ (0.106 lb/in³), heavier than 91% of composite grades.
Mechanical13
A356/Al2O3/20p T7 has a yield strength of 245 MPa (35.5 ksi) and a tensile strength of 290 MPa (42.1 ksi) — weaker than 58% of composite grades. Elongation at break is 1.2% and the elastic modulus is 98 GPa (14.2 Msi).
Thermal6
A356/Al2O3/20p T7 is rated for continuous service to 230°C (446 °F). It conducts heat at 145 W/m·K (83.8 BTU/hr·ft·°F), better than 91% of composite grades. Thermal expansion is 17.5 µm/m·K (9.72 µin/in·°F).
Electrical1
A356/Al2O3/20p T7 has an electrical resistivity of 5.2×10⁻⁸ Ω·m.
Chemical & Environmental3
Corrosion resistance is good (60/100), worse than 79% of composite grades. UV resistance is excellent.
Sustainability4
Producing a kilogram of A356/Al2O3/20p T7 takes about 210 MJ of energy and emits 14 kg of CO₂ — less than 52% of composite grades. Typical recycled content is 10%.
Manufacturability2
A356/Al2O3/20p T7's machinability is poor (22/100, worse than 73% of composite grades).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with A356/Al2O3/20p T7
Is A356/Al2O3/20p easy to machine?
Highly abrasive — use PCD or CVD-diamond tooling, high speed/low feed, flood coolant; carbide tools wear in minutes.
Can A356/Al2O3/20p be welded?
Fusion welding is problematic (particle clustering, Al4C3-free but oxide segregation); prefer mechanical joining, adhesive bonding or friction stir welding with MMC-rated tools.
Can A356/Al2O3/20p be formed, bent or molded?
Cast by stir/rheocasting into sand, permanent-mould or squeeze-cast tooling; keep melt stirred and avoid long holding to prevent particle settling; not cold formable.
What surface finishes work on A356/Al2O3/20p?
Anodizing gives a patchy film over exposed Al2O3 particles; chromate/Ni-plating and painting work well, honing/lapping preferred over high-gloss polishing.
A356/Al2O3/20p 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 |
|---|---|---|
| Al2O3 particulatevol % of composite (≈27 wt %); typical mean particle size 10–20 µm | 18 – 22 | 20 |
| Simatrix A356 basis | 6.5 – 7.5 | 7 |
| Mgmatrix; also aids particle wetting | 0.25 – 0.45 | 0.35 |
| Fematrix impurity limit | ≤ 0.2 | 0.12 |
| Tigrain refiner | ≤ 0.2 | 0.12 |
| Mn | ≤ 0.1 | 0.03 |
| Zn | ≤ 0.1 | 0.03 |
| Cu | ≤ 0.2 | 0.05 |
| Almatrix balance | balance | — |
A356/Al2O3/20p T7 — frequently asked
What is A356/Al2O3/20p T7 used for?
A356/Al2O3/20p T7 is typically used for automotive brake components, engine pistons, wear-resistant castings and pump housings. In short: wear-resistant cast aluminum; higher modulus than A356; needs diamond tooling.
What is the yield strength of A356/Al2O3/20p T7?
A356/Al2O3/20p T7 has a typical yield strength of 245 MPa (35.5 ksi) and a tensile strength of 290 MPa (42.1 ksi) — weaker than 58% of composite grades. Strength varies by condition: see the 4 listed tempers.
Is A356/Al2O3/20p T7 easy to machine?
Not especially — machinability is rated poor (22/100, worse than 73% of composite grades). Highly abrasive — use PCD or CVD-diamond tooling, high speed/low feed, flood coolant; carbide tools wear in minutes.
Can A356/Al2O3/20p T7 be welded?
Fusion welding is problematic (particle clustering, Al4C3-free but oxide segregation); prefer mechanical joining, adhesive bonding or friction stir welding with MMC-rated tools.
What surface finishes work on A356/Al2O3/20p T7?
Anodizing gives a patchy film over exposed Al2O3 particles; chromate/Ni-plating and painting work well, honing/lapping preferred over high-gloss polishing.
Can A356/Al2O3/20p T7 be formed, bent or molded?
Cast by stir/rheocasting into sand, permanent-mould or squeeze-cast tooling; keep melt stirred and avoid long holding to prevent particle settling; not cold formable.
What is the maximum service temperature of A356/Al2O3/20p T7?
A356/Al2O3/20p T7 is rated for continuous use to about 230°C (446 °F), and briefly to 300°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between A356/Al2O3/20p T6 and A356/Al2O3/20p F?
T6 is the default condition — standard delivery condition for structural and brake/piston applications: peak strength with maximum stiffness benefit from the alumina. F: lowest-cost condition for non-critical wear parts where stiffness and CTE, not strength, drive the design. Yield strength is 290 MPa in T6 versus 125 MPa in F.
Sources
- Duralcan Aluminum Matrix Composites — cast composite property data (F3A/W6A series) — Alcan/Duralcan (1995)
- ASM Handbook Vol. 21: Composites — Discontinuously Reinforced Aluminum — ASM International (2001)
- ASM Handbook Vol. 2: Properties and Selection — Nonferrous Alloys (A356 matrix data) — ASM International (1990)
- GB/T 1173 (A356 / ZL101A matrix basis) — SAC (2013)
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.