Aluminum 355 vs 851.0
Aluminum · grade comparison
Aluminum 355 and 851.0 are both aluminum grades. 355 is the stronger of the two: yield strength 180 MPa (26.1 ksi) against 76 MPa (11 ksi) for 851.0, about 137% more; tensile strength follows at 250 MPa (36.3 ksi) vs 140 MPa (20.3 ksi). In exchange, 851.0 is the more ductile: elongation 5% versus 3% for 355, and 355 is harder (85 HB vs 45 HB). 355 is lighter (2.71 g/cm³ vs 2.83 g/cm³ for 851.0) and 355 runs hotter in service (175°C vs 150°C continuous). On the shop floor, 851.0 machines more easily (excellent vs good), 355 welds better (good vs poor), and 355 sits in a lower cost tier (budget, $) than 851.0 (premium, $$$).
355Choose it when strength drives the design, or when weight is the constraint.
851.0Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
355 vs 851.0: 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.
Bulk Modulus
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Hardness, Brinell
Compressive Strength
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 71 GPa10.3 Msi · Shear Modulus 26.5 GPa3.8 Msi · Poisson's Ratio 0.33
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
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
Max Service Temperature (continuous)
Min Service Temperature
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Same in both: Corrosion Resistance 45 / 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
Polishability
Same in both: Brazeability / Solderability 25 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Typical Recycled Content
Same in both: Embodied Carbon (primary production) 12 kg CO₂/kg · Embodied Water 1,100 L/kg132 gal/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 | 355 | 851.0 |
|---|---|---|
| CNC machining | Yes | — |
| Default condition | — | — |
| Relative cost | $ Budget | $$$ Premium |
| 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.
355 vs 851.0 — frequently asked
Is 355 stronger than 851.0?
Yes. 355 has a typical yield strength of 180 MPa (26.1 ksi) against 76 MPa (11 ksi) for 851.0 — about 137% more. Tensile strength is 250 MPa (36.3 ksi) vs 140 MPa (20.3 ksi).
Which is cheaper, 355 or 851.0?
355 is the lower-cost material: it sits in the budget tier ($) while 851.0 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, 355 or 851.0?
851.0. Its machinability rates excellent (88/100) against good (62/100) for 355; for welding the order is 355 first (good, 55/100) then 851.0 (poor, 20/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 355 and 851.0 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.