Aluminum AlSi7Mg
EN AlSi7Mg · ASTM A356.0
AlSi7Mg is the hypoeutectic Al-Si-Mg foundry composition (EN AC-42000, A356.0, ZL101) supplied as LPBF powder and also used for sand, permanent-mould and low-pressure castings.
Values for the As Printed condition
AlSi7Mg tempers and conditions
AlSi7Mg is supplied in 8 conditions, soft to hard. As Printed is the default FabDigit quotes; the values on this page are for it.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As fabricated | EN AC-42000 (AlSi7Mg / A356) in the as-cast, non-heat-treated F condition — modest strength, good ductility and excellent castability. | 90 | 170 | 4 | 55 HB | 40 % IACS |
Hot isostatic pressed | Choose for fatigue- and fracture-critical aerospace parts: HIP closes internal gas/lack-of-fusion porosity and homogenises the structure, giving high ductility at annealed-level strength. | 185 | 275 | 16 | 85 HB | 38 % IACS |
Cast | Under-aged casting temper of EN AC-42000: slightly lower strength than T6 but noticeably higher elongation, toughness and fatigue crack resistance for structural castings. | 195 | 250 | 8 | 80 HB | 39 % IACS |
~300 °C / 2 h anneal after build | Standard first step for thin-wall or distortion-sensitive geometry: removes build residual stress and raises ductility at some cost in strength. | 200 | 300 | 12 | 90 HB | 36 % IACS |
T6 | Sand/permanent-mould EN AC-42000 solution treated near 540 °C, water quenched and peak-aged for maximum strength and hardness with limited ductility. | 220 | 275 | 5 | 85 HB | 39 % IACS |
As PrintedDefault as-built LPBF, no post heat treatment | Highest as-built strength from the ultrafine cellular Si network; use for non-critical or dimensionally simple parts where residual stress and anisotropy are acceptable. | 240 | 350 | 8 | 105 HB | 28 % IACS |
hot isostatic pressing followed by solution treat and artificial age | Best overall combination for qualified flight hardware: porosity-free structure with near-T6 strength and clearly improved elongation and fatigue life. | 290 | 365 | 12 | 112 HB | 39 % IACS |
Solution heat treated and artificially aged | Highest strength condition and the usual delivery state for structural brackets and housings; accept some ductility loss and quench-distortion risk. | 300 | 380 | 8 | 115 HB | 39 % IACS |
What is AlSi7Mg?
AlSi7Mg is the hypoeutectic Al-Si-Mg foundry composition (EN AC-42000, A356.0, ZL101) supplied as LPBF powder and also used for sand, permanent-mould and low-pressure castings. Engineers select it when printed parts need more ductility than AlSi10Mg at comparable cost: 240 MPa yield, 350 MPa tensile, 8 % elongation, 105 HB, 71 GPa modulus and 130 W/m·K, with T6, HIP and HIP+T6 routes available for fatigue-rated hardware. Service is limited to 120 °C, primary silicon is abrasive to tooling and anodised colour is dark grey; AlSi10Mg is the nearest alternative. AlSi7Mg has a density of 2.67 g/cm³ (0.0965 lb/in³), lighter than 78% of aluminum grades. It melts at 557°C (1,035 °F). AlSi7Mg has a yield strength of 240 MPa (34.8 ksi) and a tensile strength of 350 MPa (50.8 ksi) — stronger than 63% of aluminum grades. Elongation at break is 8% and the elastic modulus is 71 GPa (10.3 Msi).
What is AlSi7Mg used for?
- Aerospace housings and fittings
- Cast-replacement structural brackets
- Valve bodies and manifolds
- Satellite and instrument frames
- Pump and gearbox housings
- Motorsport suspension components
- Thin-wall thermal covers
Limitations
- Low electrical conductivity — 28 % IACS, worse than 82% of aluminum grades
- Limited service temperature — 120°C (248 °F), worse than 79% of aluminum grades
AlSi7Mg properties
Typical room-temperature values for AlSi7Mg-As Printed; bars are the position among aluminum grades.
Physical3
AlSi7Mg has a density of 2.67 g/cm³ (0.0965 lb/in³), lighter than 78% of aluminum grades. It melts at 557°C (1,035 °F).
Mechanical14
AlSi7Mg has a yield strength of 240 MPa (34.8 ksi) and a tensile strength of 350 MPa (50.8 ksi) — stronger than 63% of aluminum grades. Elongation at break is 8% and the elastic modulus is 71 GPa (10.3 Msi).
Thermal6
AlSi7Mg is rated for continuous service to 120°C (248 °F). It conducts heat at 130 W/m·K (75.1 BTU/hr·ft·°F), worse than 65% of aluminum grades. Thermal expansion is 21.5 µm/m·K (11.9 µin/in·°F).
Electrical3
AlSi7Mg conducts electricity at 28 % IACS, worse than 82% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (58/100), better than 57% of aluminum grades.
Sustainability4
Producing a kilogram of AlSi7Mg takes about 215 MJ of energy and emits 13 kg of CO₂ — more than 93% of aluminum grades. Typical recycled content is 10%.
Manufacturability8
AlSi7Mg's machinability is good (58/100, worse than 54% of aluminum grades); weldability very good (70/100); formability poor (20/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the aluminum family
Yield strength against density for every aluminum grade FabDigit runs. AlSi7Mg is highlighted; hover a dot for its name, or open the interactive family chart.
Working with AlSi7Mg
Is AlSi7Mg easy to machine?
Machines like a Si-bearing casting alloy: use polished-flute carbide or PCD tools, high speed, low feed and flood coolant/air-blast to stop chip welding; expect abrasive tool wear from primary Si.
Can AlSi7Mg be welded?
Readily laser- or TIG-welded and AM-repairable, best with 4043/4047 filler; avoid autogenous welding of thick sections in T6 as the HAZ softens and requires re-solution/age.
Can AlSi7Mg be formed, bent or molded?
Not a formable alloy — geometry comes from the build; design self-supporting angles >45°, keep walls ≥0.4 mm and stress-relieve on the plate before cutting off supports to limit distortion.
Manufacturability
The process limits FabDigit's quote engine applies to AlSi7Mg. Design inside these and the part quotes instantly; outside them it routes to an engineer.
3D printing
| Technologies | DMLS |
|---|---|
| Layer height | 20 – 60 µmdefault 30 µm |
| Minimum wall / feature | 0.5 / 0.3 mm |
| Build envelope | 250 × 250 × 325 mm |
| Supports | Yes |
| Anisotropy | Mild |
| Mandatory post-processing | heat treatment |
AlSi7Mg 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 | 6.5 – 7.5 | 7 |
| Mg0.55–0.6 typical for AM powder | 0.45 – 0.7 | 0.6 |
| Ti | 0.04 – 0.2 | 0.12 |
| FeF357/AM powder often ≤0.12 | ≤ 0.2 | 0.1 |
| Cu | ≤ 0.05 | 0.01 |
| Mn | ≤ 0.1 | 0.01 |
| Zn | ≤ 0.07 | 0.01 |
| Be0.04–0.07 in A357; F357 is beryllium-free and is the grade normally used for AM | ≤ 0.07 | 0 |
| Opowder oxygen pickup limit | ≤ 0.05 | 0.02 |
| Others (each/total)0.05 each / 0.15 total | ≤ 0.15 | |
| Al | balance |
What surface finishes work on AlSi7Mg?
Blast/tumble or machine off the as-built roughness (Ra 8–15 µm), then chemical conversion (chromate-free Ti/Zr) or hard/Type II anodise; anodised colour is dark grey, and shot-peening plus HIP is the usual route to fatigue-rated surfaces.
Surface treatments FabDigit runs on aluminum parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Metal Finish
Equivalent designations
Standards and trade names that resolve to Aluminum AlSi7Mg in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- A356.0
- EN / DIN / Werkstoff-Nr.
- AlSi7Mg0.6AC-42000G-AlSi7MgAlSi7Mg0.3
- Similar grades
- ZL101
How much does AlSi7Mg cost?
AlSi7Mg is a premium-cost aluminum ($$$), pricier than about 57% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
AlSi7Mg — frequently asked
What is AlSi7Mg used for?
AlSi7Mg is typically used for aerospace housings and fittings, cast-replacement structural brackets, valve bodies and manifolds, satellite and instrument frames, pump and gearbox housings and motorsport suspension components. In short: castable LPBF aluminum alloy.
What is the yield strength of AlSi7Mg?
AlSi7Mg has a typical yield strength of 240 MPa (34.8 ksi) and a tensile strength of 350 MPa (50.8 ksi) — stronger than 63% of aluminum grades. Strength varies by condition: see the 8 listed tempers.
Is AlSi7Mg easy to machine?
Reasonably — machinability is rated good (58/100, worse than 54% of aluminum grades). Machines like a Si-bearing casting alloy: use polished-flute carbide or PCD tools, high speed, low feed and flood coolant/air-blast to stop chip welding; expect abrasive tool wear from primary Si.
Can AlSi7Mg be welded?
Yes — weldability is rated very good (70/100). Readily laser- or TIG-welded and AM-repairable, best with 4043/4047 filler; avoid autogenous welding of thick sections in T6 as the HAZ softens and requires re-solution/age.
What surface finishes work on AlSi7Mg?
Blast/tumble or machine off the as-built roughness (Ra 8–15 µm), then chemical conversion (chromate-free Ti/Zr) or hard/Type II anodise; anodised colour is dark grey, and shot-peening plus HIP is the usual route to fatigue-rated surfaces.
Can AlSi7Mg be formed, bent or molded?
Not a formable alloy — geometry comes from the build; design self-supporting angles >45°, keep walls ≥0.4 mm and stress-relieve on the plate before cutting off supports to limit distortion.
What is the maximum service temperature of AlSi7Mg?
AlSi7Mg is rated for continuous use to about 120°C (248 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between AlSi7Mg As Printed and AlSi7Mg-F?
As Printed is the default condition — highest as-built strength from the ultrafine cellular Si network; use for non-critical or dimensionally simple parts where residual stress and anisotropy are acceptable. F: eN AC-42000 (AlSi7Mg / A356) in the as-cast, non-heat-treated F condition — modest strength, good ductility and excellent castability. Yield strength is 240 MPa in As Printed versus 90 MPa in F.
How much does AlSi7Mg cost?
AlSi7Mg is a premium-cost aluminum ($$$), pricier than about 57% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Can FabDigit make parts in AlSi7Mg?
Yes — AlSi7Mg is available for 3D printing with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM F3318 — Additive Manufacturing of Aluminium Alloy AlSi7Mg0.6 (F357) via Laser PBF — ASTM International (2018)
- AMS 4289 / AMS 2771 — A357 casting alloy and heat treatment of aluminium castings — SAE International (2019)
- EN 1706 (EN AC-42200 AlSi7Mg0.6) — CEN (2020)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- LPBF AlSi7Mg0.6 / F357 powder and material datasheets — EOS / SLM Solutions / Constellium-Aheadd class producers (2023)
- Al-Si-Mg additive manufacturing property compilations — MMPDS-supporting AM literature and NIST AM Bench reports (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.