Aluminum AL25-T6 vs AL25-T7
Aluminum · AL25 temper comparison
AL25-T6 and AL25-T7 are two conditions of the same aluminum grade, AL25: T6 (solution heat treated and artificially aged) versus T7 (solution heat treated and overaged (stabilized)). The chemistry is identical, so every difference below comes from the condition. AL25-T6 is the stronger of the two: yield strength 205 MPa (29.7 ksi) against 170 MPa (24.7 ksi) for AL25-T7, about 21% more; tensile strength follows at 230 MPa (33.4 ksi) vs 195 MPa (28.3 ksi). In exchange, AL25-T7 is the more ductile: elongation 0.9% versus 0.5% for AL25-T6, and AL25-T6 is harder (110 HB vs 95 HB). AL25-T7 runs hotter in service (300°C vs 250°C continuous) and AL25-T7 conducts heat better (140 W/m·K vs 120 W/m·K).
AL25-T6Choose it when strength drives the design.
AL25-T7Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
AL25-T6 vs AL25-T7: 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)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 80 GPa11.6 Msi · Shear Modulus 30 GPa4.4 Msi · Bulk Modulus 73 GPa10.6 Msi · Poisson's Ratio 0.33 · Hardness, Rockwell B 55 HRB
Physical
Density and transition temperatures.
Same in both: Density 2.73 g/cm³0.1 lb/in³ · Melting Point (Solidus) 510°C950 °F · Liquidus Temperature 585°C1,085 °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 880 J/kg·K0.21 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 19 µm/m·K10.6 µin/in·°F · Latent Heat of Fusion 470 J/g202 BTU/lb · Min Service Temperature -50°C-58 °F
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) -0.78 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Same in both: Machinability Rating (AISI 1212 = 100 %) 55% · Castability 85 / 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 1,200 L/kg144 gal/lb · Typical Recycled Content 60%
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.
AL25-T6 vs AL25-T7 — frequently asked
Is AL25-T6 stronger than AL25-T7?
Yes. AL25-T6 has a typical yield strength of 205 MPa (29.7 ksi) against 170 MPa (24.7 ksi) for AL25-T7 — about 21% more. Tensile strength is 230 MPa (33.4 ksi) vs 195 MPa (28.3 ksi).
Which condition does FabDigit quote by default, T6 or T7?
T1 is the default AL25 condition in the FabDigit quote flow (neither T6 nor T7). 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 AL25-T6 over AL25-T7?
Pick AL25-T6 when strength drives the design. Pick AL25-T7 when the part is bent, formed or impact-loaded, or when the part sees heat.
Ready to make it?
Upload a CAD file and FabDigit prices the part in AL25-T6 and AL25-T7 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.