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Steel SCCrM3-QT vs SCCrM3-SR

Steel · SCCrM3 temper comparison

SCCrM3-QT and SCCrM3-SR are two conditions of the same steel grade, SCCrM3: QT (quenched and tempered) versus SR (stress relieved). The chemistry is identical, so every difference below comes from the condition. SCCrM3-QT is the stronger of the two: yield strength 720 MPa (104 ksi) against 480 MPa (69.6 ksi) for SCCrM3-SR, about 50% more; tensile strength follows at 900 MPa (131 ksi) vs 760 MPa (110 ksi). In exchange, SCCrM3-SR is the more ductile: elongation 10% versus 9% for SCCrM3-QT, and SCCrM3-QT is harder (270 HB vs 225 HB).

SCCrM3-QTChoose it when strength drives the design.

SCCrM3-SRChoose it when the part is bent, formed or impact-loaded.

SCCrM3-QT vs SCCrM3-SR: properties

SCCrM3-QTSCCrM3-SR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

900 MPa131 ksi
760 MPa110 ksi

Yield Strength (0.2% offset)

720 MPa104 ksi
480 MPa69.6 ksi

Elongation at Break

9%
10%

Reduction in Area

25%
22%

Compressive Strength

720 MPa104 ksi
480 MPa69.6 ksi

Shear Strength

540 MPa78.3 ksi
460 MPa66.7 ksi

Fatigue Strength (Endurance Limit)

370 MPa53.7 ksi
310 MPa45 ksi

Fracture Toughness (K_IC)

70 MPa·√m63.7 ksi·√in
55 MPa·√m50.1 ksi·√in

Charpy V-Notch Impact (RT)

25 J18.4 ft·lbf
18 J13.3 ft·lbf

Hardness, Brinell

270 HB
225 HB

Hardness, Rockwell C

27 HRC
20 HRC

Hardness, Vickers

285 HV
236 HV

Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,495°C2,723 °F

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

42 W/m·K24.3 BTU/hr·ft·°F
43 W/m·K24.8 BTU/hr·ft·°F

Max Service Temperature (continuous)

450°C842 °F
425°C797 °F

Same in both: Specific Heat Capacity 460 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 250 J/g107 BTU/lb · Min Service Temperature -30°C-22 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

2.2×10⁻⁷ Ω·m8.66 µΩ·in
2.15×10⁻⁷ Ω·m8.46 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Corrosion Resistance 13 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

40 / 100
42 / 100

Machinability Rating (AISI 1212 = 100 %)

45%
48%

Weldability

40 / 100
45 / 100

Formability (cold)

10 / 100
12 / 100

Same in both: Castability 65 / 100 · Brazeability / Solderability 45 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 1.9 kg CO₂/kg · Embodied Water 45 L/kg5.4 gal/lb · Typical Recycled Content 80%

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.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scaleSCCrM3

SCCrM3-QT vs SCCrM3-SR — frequently asked

Is SCCrM3-QT stronger than SCCrM3-SR?

Yes. SCCrM3-QT has a typical yield strength of 720 MPa (104 ksi) against 480 MPa (69.6 ksi) for SCCrM3-SR — about 50% more. Tensile strength is 900 MPa (131 ksi) vs 760 MPa (110 ksi).

Which condition does FabDigit quote by default, QT or SR?

QT is the default SCCrM3 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 welds better, SCCrM3-QT or SCCrM3-SR?

SCCrM3-SR. Its weldability rates fair (45/100) against fair (40/100) for SCCrM3-QT.

Ready to make it?

Upload a CAD file and FabDigit prices the part in SCCrM3-QT and SCCrM3-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.