Aluminum LM25-F vs LM25-T6
Aluminum · LM25 temper comparison
LM25-F and LM25-T6 are two conditions of the same aluminum grade, LM25: F (as fabricated) versus T6 (solution heat treated and artificially aged). The chemistry is identical, so every difference below comes from the condition. LM25-T6 is the stronger of the two: yield strength 215 MPa (31.2 ksi) against 85 MPa (12.3 ksi) for LM25-F, about 153% more; tensile strength follows at 250 MPa (36.3 ksi) vs 150 MPa (21.8 ksi). LM25-T6 is harder — 95 HB against 60 HB for LM25-F — which matters for wear surfaces and threads. On the shop floor, LM25-T6 machines more easily (65 vs 55 out of 100).
LM25-T6Choose it when strength drives the design, or when surface hardness matters.
LM25-F vs LM25-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)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Same in both: Elastic (Young's) Modulus 71 GPa10.3 Msi · Shear Modulus 26.5 GPa3.8 Msi · Bulk Modulus 70 GPa10.2 Msi · Poisson's Ratio 0.33 · Elongation at Break 3% · Fracture Toughness (K_IC) 22 MPa·√m20 ksi·√in · Hardness, Vickers 100 HV
Physical
Density and transition temperatures.
Same in both: Density 2.68 g/cm³0.1 lb/in³ · Melting Point (Solidus) 555°C1,031 °F · Liquidus Temperature 615°C1,139 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Same in both: Specific Heat Capacity 963 J/kg·K0.23 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 22 µm/m·K12.2 µin/in·°F · Latent Heat of Fusion 389 J/g167 BTU/lb · Max Service Temperature (continuous) 150°C302 °F · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Same in both: Electrical Resistivity 4.4×10⁻⁸ Ω·m1.73 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.83 V · Corrosion Resistance 65 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Same in both: Machinability Rating (AISI 1212 = 100 %) 70% · Weldability 75 / 100 · Formability (cold) 10 / 100 · Castability 95 / 100 · Brazeability / Solderability 35 / 100 · Polishability 45 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 190 MJ/kg81,685 BTU/lb · Embodied Carbon (primary production) 12 kg CO₂/kg · Embodied Water 1,200 L/kg144 gal/lb · Typical Recycled Content 50%
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.
LM25-F vs LM25-T6 — frequently asked
Is LM25-T6 stronger than LM25-F?
Yes. LM25-T6 has a typical yield strength of 215 MPa (31.2 ksi) against 85 MPa (12.3 ksi) for LM25-F — about 153% more. Tensile strength is 250 MPa (36.3 ksi) vs 150 MPa (21.8 ksi).
Which condition does FabDigit quote by default, F or T6?
T6 is the default LM25 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.
Which is easier to machine, LM25-F or LM25-T6?
LM25-T6, by a small margin. Both rate good for machinability — 65/100 against 55/100 for LM25-F.
Ready to make it?
Upload a CAD file and FabDigit prices the part in LM25-F and LM25-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.