Aluminum AlSi12 Stress Relieved vs AlSi12-T6
Aluminum · AlSi12 temper comparison
AlSi12 Stress Relieved and AlSi12-T6 are two conditions of the same aluminum grade, AlSi12: Stress Relieved versus T6 (solution heat treated and artificially aged). The chemistry is identical, so every difference below comes from the condition. AlSi12 Stress Relieved is the stronger of the two: yield strength 180 MPa (26.1 ksi) against 150 MPa (21.8 ksi) for AlSi12-T6, about 20% more; tensile strength follows at 300 MPa (43.5 ksi) vs 265 MPa (38.4 ksi). In exchange, AlSi12-T6 is the more ductile: elongation 12% versus 9% for AlSi12 Stress Relieved, and AlSi12 Stress Relieved is harder (78 HB vs 70 HB).
AlSi12 Stress RelievedChoose it when strength drives the design.
AlSi12-T6Choose it when the part is bent, formed or impact-loaded.
AlSi12 Stress Relieved vs AlSi12-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.
AlSi12 Stress RelievedAlSi12-T6
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Fatigue Strength (Endurance Limit)
Hardness, Brinell
Hardness, Vickers
Same in both: Shear Modulus 27 GPa3.9 Msi · Bulk Modulus 74 GPa10.7 Msi · Poisson's Ratio 0.33 · Compressive Strength 420 MPa60.9 ksi · Shear Strength 240 MPa34.8 ksi · Fracture Toughness (K_IC) 17 MPa·√m15.5 ksi·√in · Charpy V-Notch Impact (RT) 4 J3 ft·lbf
Physical
Density and transition temperatures.
Same in both: Density 2.67 g/cm³0.1 lb/in³ · Melting Point (Solidus) 574°C1,065 °F · Liquidus Temperature 585°C1,085 °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) 20.4 µm/m·K11.3 µin/in·°F · Latent Heat of Fusion 510 J/g219 BTU/lb · Max Service Temperature (continuous) 150°C302 °F · 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) -0.83 V · Corrosion Resistance 55 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Same in both: Weldability 80 / 100 · Formability (cold) 15 / 100 · Castability 95 / 100 · Brazeability / Solderability 35 / 100 · Polishability 55 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 215 MJ/kg92,433 BTU/lb · Embodied Carbon (primary production) 13 kg CO₂/kg · Embodied Water 1,200 L/kg144 gal/lb · Typical Recycled Content 10%
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.
AlSi12 Stress Relieved vs AlSi12-T6 — frequently asked
Is AlSi12 Stress Relieved stronger than AlSi12-T6?
Yes. AlSi12 Stress Relieved has a typical yield strength of 180 MPa (26.1 ksi) against 150 MPa (21.8 ksi) for AlSi12-T6 — about 20% more. Tensile strength is 300 MPa (43.5 ksi) vs 265 MPa (38.4 ksi).
Which condition does FabDigit quote by default, Stress Relieved or T6?
As Printed is the default AlSi12 condition in the FabDigit quote flow (neither Stress Relieved nor T6). 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 AlSi12 Stress Relieved over AlSi12-T6?
Pick AlSi12 Stress Relieved when strength drives the design. Pick AlSi12-T6 when the part is bent, formed or impact-loaded.
Ready to make it?
Upload a CAD file and FabDigit prices the part in AlSi12 Stress Relieved and AlSi12-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.