Aluminum AlSi7Mg vs EN AC-42100
Aluminum · grade comparison
Aluminum AlSi7Mg and EN AC-42100 are both aluminum grades. AlSi7Mg is the stronger of the two: tensile strength 350 MPa (50.8 ksi) against 295 MPa (42.8 ksi) for EN AC-42100, about 19% more. AlSi7Mg is the more ductile: elongation 8% versus 6% for EN AC-42100, and AlSi7Mg is harder (105 HB vs 95 HB). EN AC-42100 runs hotter in service (150°C vs 120°C continuous) and EN AC-42100 conducts heat better (151 W/m·K vs 130 W/m·K). On the shop floor, EN AC-42100 machines more easily (very good vs good) and EN AC-42100 sits in a lower cost tier (standard, $$) than AlSi7Mg (premium, $$$).
AlSi7MgChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.
EN AC-42100Choose it when the part sees heat, or when the part is machined in volume.
AlSi7Mg vs EN AC-42100: 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
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Hardness, Brinell
Hardness, Vickers
Same in both: Poisson's Ratio 0.33 · Charpy V-Notch Impact (RT) 6 J4.4 ft·lbf
Physical
Density and transition temperatures.
Density
Same in both: Melting Point (Solidus) 557°C1,035 °F · Liquidus Temperature 613°C1,135 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Max Service Temperature (continuous)
Same in both: Specific Heat Capacity 963 J/kg·K0.23 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 21.5 µm/m·K11.9 µin/in·°F · Latent Heat of Fusion 389 J/g167 BTU/lb · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Corrosion Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Castability
Polishability
Same in both: Brazeability / Solderability 30 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
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 | AlSi7Mg | EN AC-42100 |
|---|---|---|
| 3D printing | Yes | — |
| Default condition | As Printed | — |
| Relative cost | $$$ Premium | $$ Standard |
| Min. machined wall | — | — |
| Best machined surface | — | — |
| Anodized (Aluminum AM) | Yes | — |
| Plated (Metal AM) | Yes | — |
They share 4 finishes: Electroless Nickel (EN), Epoxy Coating, Gold Plating, Silver Plating.
AlSi7Mg vs EN AC-42100 — frequently asked
Is AlSi7Mg stronger than EN AC-42100?
Yes. AlSi7Mg has a typical tensile strength of 350 MPa (50.8 ksi) against 295 MPa (42.8 ksi) for EN AC-42100 — about 19% more.
Which is cheaper, AlSi7Mg or EN AC-42100?
EN AC-42100 is the lower-cost material: it sits in the standard tier ($$) while AlSi7Mg is premium ($$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
Which is easier to machine, AlSi7Mg or EN AC-42100?
EN AC-42100. Its machinability rates very good (70/100) against good (58/100) for AlSi7Mg; for welding the order is EN AC-42100 first (very good, 75/100) then AlSi7Mg (very good, 70/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in AlSi7Mg and EN AC-42100 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.