Steel SCr415-A vs SCr415-QT
Steel · SCr415 temper comparison
SCr415-A and SCr415-QT are two conditions of the same steel grade, SCr415: A (solution annealed) versus QT (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. SCr415-QT is the stronger of the two: yield strength 760 MPa (110 ksi) against 340 MPa (49.3 ksi) for SCr415-A, about 124% more; tensile strength follows at 1,000 MPa (145 ksi) vs 540 MPa (78.3 ksi). In exchange, SCr415-A is the more ductile: elongation 26% versus 13% for SCr415-QT, and SCr415-QT is harder (300 HB vs 160 HB). SCr415-A runs hotter in service (350°C vs 200°C continuous). On the shop floor, SCr415-A machines more easily (good vs fair) and SCr415-A welds better (good vs poor).
SCr415-AChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
SCr415-QTChoose it when strength drives the design.
SCr415-A vs SCr415-QT: 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
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Same in both: Elastic (Young's) Modulus 206 GPa29.9 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Compressive Strength 340 MPa49.3 ksi · Shear Strength 330 MPa47.9 ksi · Hardness, Rockwell B 84 HRB
Physical
Density and transition temperatures.
Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °F · Liquidus Temperature 1,500°C2,732 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 44 W/m·K25.4 BTU/hr·ft·°F · Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.9 µm/m·K6.6 µin/in·°F · Latent Heat of Fusion 260 J/g112 BTU/lb · 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) -0.62 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 65 / 100 · Polishability 60 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 27 MJ/kg11,608 BTU/lb · Embodied Carbon (primary production) 2 kg CO₂/kg · Embodied Water 45 L/kg5.4 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.
SCr415-A vs SCr415-QT — frequently asked
Is SCr415-QT stronger than SCr415-A?
Yes. SCr415-QT has a typical yield strength of 760 MPa (110 ksi) against 340 MPa (49.3 ksi) for SCr415-A — about 124% more. Tensile strength is 1,000 MPa (145 ksi) vs 540 MPa (78.3 ksi).
Which condition does FabDigit quote by default, A or QT?
A is the default SCr415 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, SCr415-A or SCr415-QT?
SCr415-A. Its machinability rates good (60/100) against fair (40/100) for SCr415-QT; for welding the order is SCr415-A first (good, 60/100) then SCr415-QT (poor, 30/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in SCr415-A and SCr415-QT 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.