Steel SCM440 Annealed vs SCM440 Q&T
Steel · SCM440 temper comparison
SCM440 Annealed and SCM440 Q&T are two conditions of the same steel grade, SCM440: Annealed versus Q&T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. SCM440 Q&T is the stronger of the two: yield strength 880 MPa (128 ksi) against 415 MPa (60.2 ksi) for SCM440 Annealed, about 112% more; tensile strength follows at 1,000 MPa (145 ksi) vs 655 MPa (95 ksi). In exchange, SCM440 Annealed is the more ductile: elongation 25% versus 16% for SCM440 Q&T, and SCM440 Q&T is harder (285 HB vs 197 HB). On the shop floor, SCM440 Annealed machines more easily (good vs fair) and SCM440 Annealed welds better (50 vs 40 out of 100).
SCM440 AnnealedChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
SCM440 Q&TChoose it when strength drives the design.
SCM440 Annealed vs SCM440 Q&T: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all steel 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 steel 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
Reduction in Area
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell C
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Compressive Strength 600 MPa87 ksi
Physical
Density and transition temperatures.
Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,416°C2,581 °F · Liquidus Temperature 1,465°C2,669 °F
Thermal
How each material carries heat and how hot it can run.
Same in both: Thermal Conductivity 42.6 W/m·K24.6 BTU/hr·ft·°F · Specific Heat Capacity 473 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.3 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 247 J/g106 BTU/lb · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -40°C-40 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 7.8 % IACS · Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V · Corrosion Resistance 12 / 100
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: Brazeability / Solderability 55 / 100 · Polishability 65 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 29 MJ/kg12,468 BTU/lb · Embodied Carbon (primary production) 2.1 kg CO₂/kg · Embodied Water 55 L/kg6.6 gal/lb · Typical Recycled Content 30%
Strength versus weight
Yield strength against density for every steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
SCM440 Annealed vs SCM440 Q&T — frequently asked
Is SCM440 Q&T stronger than SCM440 Annealed?
Yes. SCM440 Q&T has a typical yield strength of 880 MPa (128 ksi) against 415 MPa (60.2 ksi) for SCM440 Annealed — about 112% more. Tensile strength is 1,000 MPa (145 ksi) vs 655 MPa (95 ksi).
Which condition does FabDigit quote by default, Annealed or Q&T?
HR is the default SCM440 condition in the FabDigit quote flow (neither Annealed nor Q&T). 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, SCM440 Annealed or SCM440 Q&T?
SCM440 Annealed. Its machinability rates good (65/100) against fair (48/100) for SCM440 Q&T; for welding the order is SCM440 Annealed first (fair, 50/100) then SCM440 Q&T (fair, 40/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in SCM440 Annealed and SCM440 Q&T 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.