Aluminum AlSi12 vs AlSi7Mg
Aluminum · grade comparison
Aluminum AlSi12 and AlSi7Mg are both aluminum grades. AlSi12 is the stronger of the two: tensile strength 400 MPa (58 ksi) against 350 MPa (50.8 ksi) for AlSi7Mg, about 14% more. In exchange, AlSi7Mg is the more ductile: elongation 8% versus 5% for AlSi12. On the shop floor, AlSi12 welds better (80 vs 70 out of 100).
AlSi12Choose it when strength drives the design, or when it will be welded.
AlSi7MgChoose it when the part is bent, formed or impact-loaded.
AlSi12 vs AlSi7Mg: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all aluminum grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all aluminum grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Shear Modulus
Bulk Modulus
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Shear Strength
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Same in both: Poisson's Ratio 0.33 · Fatigue Strength (Endurance Limit) 100 MPa14.5 ksi · Hardness, Brinell 105 HB · Hardness, Vickers 115 HV
Physical
Density and transition temperatures.
Melting Point (Solidus)
Liquidus Temperature
Same in both: Density 2.67 g/cm³0.1 lb/in³
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Same in both: Max Service Temperature (continuous) 120°C248 °F · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.83 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Castability
Brazeability / Solderability
Polishability
Machinability Rating (AISI 1212 = 100 %)
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 215 MJ/kg92,433 BTU/lb · Embodied Carbon (primary production) 13 kg CO₂/kg · Embodied Water 1,200 L/kg144 gal/lb · Typical Recycled Content 10%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
Strength versus weight
Yield strength against density for every aluminum grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | AlSi12 | AlSi7Mg |
|---|---|---|
| Default condition | As Printed | As Printed |
| Relative cost | $$$ Premium | $$$ Premium |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Both are offered for 3D printing. Both take the same 6 finishes: Anodized (Aluminum AM), Electroless Nickel (EN), Epoxy Coating, Gold Plating, Plated (Metal AM), Silver Plating.
AlSi12 vs AlSi7Mg — frequently asked
Is AlSi12 stronger than AlSi7Mg?
Yes. AlSi12 has a typical tensile strength of 400 MPa (58 ksi) against 350 MPa (50.8 ksi) for AlSi7Mg — about 14% more.
Which is cheaper, AlSi12 or AlSi7Mg?
Both sit in the same relative cost tier ($$$, premium); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, AlSi12 or AlSi7Mg?
AlSi7Mg. Its machinability rates good (58/100) against fair (50/100) for AlSi12; for welding the order is AlSi12 first (very good, 80/100) then AlSi7Mg (very good, 70/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in AlSi12 and AlSi7Mg side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.
Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.