Aluminum 331.0-T5 vs 331.0-T6
Aluminum · 331.0 temper comparison
331.0-T5 and 331.0-T6 are two conditions of the same aluminum grade, 331.0: T5 (cooled from hot working and artificially aged) versus T6 (solution heat treated and artificially aged). The chemistry is identical, so every difference below comes from the condition. 331.0-T6 is the stronger of the two: yield strength 195 MPa (28.3 ksi) against 150 MPa (21.8 ksi) for 331.0-T5, about 30% more; tensile strength follows at 250 MPa (36.3 ksi) vs 205 MPa (29.7 ksi). 331.0-T6 is harder — 95 HB against 85 HB for 331.0-T5 — which matters for wear surfaces and threads. 331.0-T5 runs hotter in service (230°C vs 200°C continuous) and 331.0-T5 conducts electricity better (29 % IACS vs 26 % IACS).
331.0-T5Choose it when the part sees heat.
331.0-T6Choose it when strength drives the design, or when surface hardness matters.
331.0-T5 vs 331.0-T6: 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)
Shear Strength
Fatigue Strength (Endurance Limit)
Hardness, Brinell
Same in both: Elastic (Young's) Modulus 79 GPa11.5 Msi · Shear Modulus 30 GPa4.4 Msi · Bulk Modulus 76 GPa11 Msi · Poisson's Ratio 0.33 · Elongation at Break 1%
Physical
Density and transition temperatures.
Same in both: Density 2.72 g/cm³0.1 lb/in³ · Melting Point (Solidus) 538°C1,000 °F · Liquidus Temperature 582°C1,080 °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) 19.3 µm/m·K10.7 µin/in·°F · Latent Heat of Fusion 460 J/g198 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).
Same in both: Galvanic Potential (seawater, vs SCE) -0.8 V · Corrosion Resistance 42 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Same in both: Machinability Rating (AISI 1212 = 100 %) 40% · Weldability 35 / 100 · Formability (cold) 5 / 100 · Castability 90 / 100 · Brazeability / Solderability 20 / 100 · Polishability 40 / 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 kg CO₂/kg · Embodied Water 1,100 L/kg132 gal/lb · Typical Recycled Content 70%
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.
331.0-T5 vs 331.0-T6 — frequently asked
Is 331.0-T6 stronger than 331.0-T5?
Yes. 331.0-T6 has a typical yield strength of 195 MPa (28.3 ksi) against 150 MPa (21.8 ksi) for 331.0-T5 — about 30% more. Tensile strength is 250 MPa (36.3 ksi) vs 205 MPa (29.7 ksi).
Which condition does FabDigit quote by default, T5 or T6?
T6 is the default 331.0 condition in the FabDigit quote flow. 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.
When should I choose 331.0-T5 over 331.0-T6?
Pick 331.0-T5 when the part sees heat. Pick 331.0-T6 when strength drives the design, or when surface hardness matters.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 331.0-T5 and 331.0-T6 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.