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Steel SCr445-CD vs SCr445-QT

Steel · SCr445 temper comparison

SCr445-CD and SCr445-QT are two conditions of the same steel grade, SCr445: CD (cold drawn) versus QT (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. SCr445-QT is the stronger of the two: yield strength 860 MPa (125 ksi) against 750 MPa (109 ksi) for SCr445-CD, about 15% more; tensile strength follows at 1,030 MPa (149 ksi) vs 900 MPa (131 ksi). SCr445-QT is the more ductile: elongation 14% versus 10% for SCr445-CD, and SCr445-QT is harder (302 HB vs 262 HB). SCr445-QT runs hotter in service (350°C vs 300°C continuous).

SCr445-QTChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.

SCr445-CD vs SCr445-QT: properties

SCr445-CDSCr445-QT

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

900 MPa131 ksi
1,030 MPa149 ksi

Yield Strength (0.2% offset)

750 MPa109 ksi
860 MPa125 ksi

Elongation at Break

10%
14%

Reduction in Area

35%
45%

Compressive Strength

770 MPa112 ksi
880 MPa128 ksi

Shear Strength

540 MPa78.3 ksi
620 MPa89.9 ksi

Fatigue Strength (Endurance Limit)

400 MPa58 ksi
480 MPa69.6 ksi

Fracture Toughness (K_IC)

55 MPa·√m50.1 ksi·√in
60 MPa·√m54.6 ksi·√in

Charpy V-Notch Impact (RT)

25 J18.4 ft·lbf
45 J33.2 ft·lbf

Hardness, Brinell

262 HB
302 HB

Hardness, Rockwell C

26 HRC
32 HRC

Hardness, Vickers

275 HV
318 HV

Same in both: Elastic (Young's) Modulus 207 GPa30 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 7.83 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °F · Liquidus Temperature 1,490°C2,714 °F

Thermal

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

Max Service Temperature (continuous)

300°C572 °F
350°C662 °F

Same in both: Thermal Conductivity 42 W/m·K24.3 BTU/hr·ft·°F · Specific Heat Capacity 475 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.2 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -25°C-13 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 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

50 / 100
42 / 100

Machinability Rating (AISI 1212 = 100 %)

55%
45%

Weldability

22 / 100
25 / 100

Formability (cold)

15 / 100
20 / 100

Same in both: Brazeability / Solderability 45 / 100 · Polishability 60 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 30 MJ/kg12,898 BTU/lb · Embodied Carbon (primary production) 2.1 kg CO₂/kg · Embodied Water 60 L/kg7.2 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.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scaleSCr445

SCr445-CD vs SCr445-QT — frequently asked

Is SCr445-QT stronger than SCr445-CD?

Yes. SCr445-QT has a typical yield strength of 860 MPa (125 ksi) against 750 MPa (109 ksi) for SCr445-CD — about 15% more. Tensile strength is 1,030 MPa (149 ksi) vs 900 MPa (131 ksi).

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

QT is the default SCr445 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, SCr445-CD or SCr445-QT?

SCr445-CD, by a small margin. Both rate fair for machinability — 50/100 against 42/100 for SCr445-QT.

Ready to make it?

Upload a CAD file and FabDigit prices the part in SCr445-CD and SCr445-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.