Aluminum AlMgSc-O vs AlMgSc-SR
Aluminum · AlMgSc temper comparison
AlMgSc-O and AlMgSc-SR are two conditions of the same aluminum grade, AlMgSc: O (annealed) versus SR (stress relieved). The chemistry is identical, so every difference below comes from the condition. AlMgSc-SR is the stronger of the two: yield strength 400 MPa (58 ksi) against 200 MPa (29 ksi) for AlMgSc-O, about 100% more; tensile strength follows at 470 MPa (68.2 ksi) vs 330 MPa (47.9 ksi). In exchange, AlMgSc-O is the more ductile: elongation 21% versus 14% for AlMgSc-SR, and AlMgSc-SR is harder (126 HB vs 80 HB). AlMgSc-O runs hotter in service (200°C vs 150°C continuous) and AlMgSc-O conducts heat better (130 W/m·K vs 105 W/m·K).
AlMgSc-OChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
AlMgSc-SRChoose it when strength drives the design.
AlMgSc-O vs AlMgSc-SR: 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.
Elastic (Young's) Modulus
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Shear Modulus 26.5 GPa3.8 Msi · Bulk Modulus 69 GPa10 Msi · Poisson's Ratio 0.33
Physical
Density and transition temperatures.
Same in both: Density 2.67 g/cm³0.1 lb/in³ · Melting Point (Solidus) 585°C1,085 °F · Liquidus Temperature 645°C1,193 °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 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 390 J/g168 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).
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
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Same in both: Castability 50 / 100 · Brazeability / Solderability 30 / 100 · Polishability 60 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 260 MJ/kg111,780 BTU/lb · Embodied Carbon (primary production) 24 kg CO₂/kg · Embodied Water 1,200 L/kg144 gal/lb · Typical Recycled Content 5%
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.
AlMgSc-O vs AlMgSc-SR — frequently asked
Is AlMgSc-SR stronger than AlMgSc-O?
Yes. AlMgSc-SR has a typical yield strength of 400 MPa (58 ksi) against 200 MPa (29 ksi) for AlMgSc-O — about 100% more. Tensile strength is 470 MPa (68.2 ksi) vs 330 MPa (47.9 ksi).
Which condition does FabDigit quote by default, O or SR?
T5 is the default AlMgSc condition in the FabDigit quote flow (neither O nor SR). 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, AlMgSc-O or AlMgSc-SR?
AlMgSc-SR. Its machinability rates good (57/100) against fair (50/100) for AlMgSc-O.
Ready to make it?
Upload a CAD file and FabDigit prices the part in AlMgSc-O and AlMgSc-SR 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.