Aluminum 356 vs AL4
Aluminum · grade comparison
Aluminum 356 and AL4 are both aluminum grades. 356 is the stronger of the two: tensile strength 262 MPa (38 ksi) against 240 MPa (34.8 ksi) for AL4, about 9% more. 356 is the more ductile: elongation 5% versus 4% for AL4, and 356 is harder (80 HB vs 75 HB). On the shop floor, 356 machines more easily (very good vs good) and 356 sits in a lower cost tier (budget, $) than AL4 (standard, $$).
356Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.
356 vs AL4: 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.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Shear Strength
Hardness, Brinell
Same in both: Elastic (Young's) Modulus 72.4 GPa10.5 Msi · Shear Modulus 27 GPa3.9 Msi · Bulk Modulus 71 GPa10.3 Msi · Poisson's Ratio 0.33 · Fatigue Strength (Endurance Limit) 90 MPa13.1 ksi · Fracture Toughness (K_IC) 20 MPa·√m18.2 ksi·√in · Charpy V-Notch Impact (RT) 5 J3.7 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.
Same in both: Thermal Conductivity 151 W/m·K87.2 BTU/hr·ft·°F · 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 · Max Service Temperature (continuous) 150°C302 °F · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 39 % IACS · Electrical Resistivity 4.4×10⁻⁸ Ω·m1.73 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.83 V · Corrosion Resistance 62 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Castability
Brazeability / Solderability
Same in both: Polishability 45 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
Same in both: Embodied Energy (primary production) 200 MJ/kg85,985 BTU/lb
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 | 356 | AL4 |
|---|---|---|
| CNC machining | Yes | — |
| Default condition | — | — |
| Relative cost | $ Budget | $$ Standard |
| Min. machined wall | 0.5 mm | — |
| Best machined surface | Ra 0.8 µm | — |
| Anodizing Type II | Yes | — |
| Cerakote | Yes | — |
| Chem Film (Alodine) | Yes | — |
| DLC | Yes | — |
| E-Coating | Yes | — |
| Electropolishing | Yes | — |
| Hard Anodize Type III w/ PTFE | Yes | — |
| Hard Anodizing Type III | Yes | — |
| Nickel Plating | Yes | — |
| PTFE Coating | Yes | — |
| Painting | Yes | — |
| Powder Coating | Yes | — |
They share 4 finishes: Electroless Nickel (EN), Epoxy Coating, Gold Plating, Silver Plating.
356 vs AL4 — frequently asked
Is 356 stronger than AL4?
Yes. 356 has a typical tensile strength of 262 MPa (38 ksi) against 240 MPa (34.8 ksi) for AL4 — about 9% more.
Which is cheaper, 356 or AL4?
356 is the lower-cost material: it sits in the budget tier ($) while AL4 is standard ($$). 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, 356 or AL4?
356. Its machinability rates very good (70/100) against good (58/100) for AL4.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 356 and AL4 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.