Aluminum 5154 vs 5251
Aluminum · grade comparison
Aluminum 5154 and 5251 are both aluminum grades, both corrosion resistant al. 5154 is the stronger of the two: yield strength 205 MPa (29.7 ksi) against 150 MPa (21.8 ksi) for 5251, about 37% more; tensile strength follows at 270 MPa (39.2 ksi) vs 210 MPa (30.5 ksi). 5154 is the more ductile: elongation 15% versus 10% for 5251, and 5154 is harder (67 HB vs 57 HB). 5251 runs hotter in service (120°C vs 65°C continuous) and 5251 conducts heat better (155 W/m·K vs 125 W/m·K).
5154Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.
5251Choose it when the part sees heat.
5154 vs 5251: 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
Shear Strength
Fatigue Strength (Endurance Limit)
Hardness, Brinell
Hardness, Vickers
Same in both: 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
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Min Service Temperature
Same in both: Specific Heat Capacity 900 J/kg·K0.21 BTU/lb·°F · Latent Heat of Fusion 395 J/g170 BTU/lb
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) -0.86 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Formability (cold)
Brazeability / Solderability
Polishability
Same in both: Machinability 45 / 100 · Machinability Rating (AISI 1212 = 100 %) 35% · Weldability 88 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Typical Recycled Content
Same in both: Embodied Carbon (primary production) 12.5 kg CO₂/kg · Embodied Water 1,200 L/kg144 gal/lb
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Same in both: Thermal Shock Resistance Index 20
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 | 5154 | 5251 |
|---|---|---|
| Default condition | — | — |
| Relative cost | $ Budget | $ Budget |
| Min. machined wall | 0.5 mm | 0.5 mm |
| Best machined surface | Ra 0.8 µm | Ra 0.8 µm |
Both are offered for CNC machining and Sheet metal. Both take the same 16 finishes: Anodizing Type II, Cerakote, Chem Film (Alodine), DLC, E-Coating, Electroless Nickel (EN), Electropolishing, Epoxy Coating, Gold Plating, Hard Anodize Type III w/ PTFE, Hard Anodizing Type III, Nickel Plating and 4 more.
5154 vs 5251 — frequently asked
Is 5154 stronger than 5251?
Yes. 5154 has a typical yield strength of 205 MPa (29.7 ksi) against 150 MPa (21.8 ksi) for 5251 — about 37% more. Tensile strength is 270 MPa (39.2 ksi) vs 210 MPa (30.5 ksi).
Which is cheaper, 5154 or 5251?
Both sit in the same relative cost tier ($, budget); the part price will be decided by machining time, tolerance and quantity rather than by the material.
When should I choose 5154 over 5251?
Pick 5154 when strength drives the design, or when the part is bent, formed or impact-loaded. Pick 5251 when the part sees heat.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 5154 and 5251 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.