Aluminum 5059-H321 vs 5059-O
Aluminum · 5059 temper comparison
5059-H321 and 5059-O are two conditions of the same aluminum grade, 5059: H321 (strain hardened and stabilized, marine temper) versus O (annealed). The chemistry is identical, so every difference below comes from the condition. 5059-H321 is the stronger of the two: yield strength 300 MPa (43.5 ksi) against 165 MPa (23.9 ksi) for 5059-O, about 82% more; tensile strength follows at 400 MPa (58 ksi) vs 345 MPa (50 ksi). In exchange, 5059-O is the more ductile: elongation 24% versus 13% for 5059-H321, and 5059-H321 is harder (100 HB vs 78 HB). On the shop floor, 5059-H321 machines more easily (45 vs 35 out of 100).
5059-H321Choose it when strength drives the design, or when the part is machined in volume.
5059-OChoose it when the part is bent, formed or impact-loaded.
5059-H321 vs 5059-O: 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
Shear Strength
Fatigue Strength (Endurance Limit)
Hardness, Brinell
Same in both: Elastic (Young's) Modulus 70 GPa10.2 Msi · Shear Modulus 26.4 GPa3.8 Msi · Bulk Modulus 69 GPa10 Msi · Poisson's Ratio 0.33 · Compressive Strength 300 MPa43.5 ksi · Fracture Toughness (K_IC) 32 MPa·√m29.1 ksi·√in
Physical
Density and transition temperatures.
Same in both: Density 2.64 g/cm³0.1 lb/in³ · Melting Point (Solidus) 570°C1,058 °F · Liquidus Temperature 640°C1,184 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Same in both: Specific Heat Capacity 900 J/kg·K0.21 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 23.5 µm/m·K13.1 µin/in·°F · Latent Heat of Fusion 395 J/g170 BTU/lb · Max Service Temperature (continuous) 65°C149 °F · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Same in both: Electrical Resistivity 6.15×10⁻⁸ Ω·m2.42 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.87 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Formability (cold)
Same in both: Machinability Rating (AISI 1212 = 100 %) 30% · Weldability 85 / 100 · Castability 25 / 100 · Brazeability / Solderability 15 / 100 · Polishability 55 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 200 MJ/kg85,985 BTU/lb · Embodied Carbon (primary production) 12.5 kg CO₂/kg · Embodied Water 1,200 L/kg144 gal/lb · Typical Recycled Content 25%
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.
5059-H321 vs 5059-O — frequently asked
Is 5059-H321 stronger than 5059-O?
Yes. 5059-H321 has a typical yield strength of 300 MPa (43.5 ksi) against 165 MPa (23.9 ksi) for 5059-O — about 82% more. Tensile strength is 400 MPa (58 ksi) vs 345 MPa (50 ksi).
Which condition does FabDigit quote by default, H321 or O?
H111 is the default 5059 condition in the FabDigit quote flow (neither H321 nor O). The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.
Which is easier to machine, 5059-H321 or 5059-O?
5059-H321, by a small margin. Both rate fair for machinability — 45/100 against 35/100 for 5059-O.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 5059-H321 and 5059-O 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.