Steel SCM432-CD vs SCM432 QT 40-45 HRC
Steel · SCM432 temper comparison
SCM432-CD and SCM432 QT 40-45 HRC are two conditions of the same steel grade, SCM432: CD (cold drawn) versus QT 40-45 HRC. The chemistry is identical, so every difference below comes from the condition. SCM432 QT 40-45 HRC is the stronger of the two: yield strength 1,250 MPa (181 ksi) against 650 MPa (94.3 ksi) for SCM432-CD, about 92% more; tensile strength follows at 1,400 MPa (203 ksi) vs 780 MPa (113 ksi). SCM432 QT 40-45 HRC is harder — 400 HB against 229 HB for SCM432-CD — which matters for wear surfaces and threads. SCM432-CD runs hotter in service (300°C vs 200°C continuous). On the shop floor, SCM432-CD machines more easily (good vs poor) and SCM432 QT 40-45 HRC forms better (fair vs poor).
SCM432-CDChoose it when the part sees heat, or when the part is machined in volume.
SCM432 QT 40-45 HRCChoose it when strength drives the design, or when surface hardness matters.
SCM432-CD vs SCM432 QT 40-45 HRC: 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
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Hardness, Brinell
Hardness, Rockwell C
Hardness, Vickers
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 · Charpy V-Notch Impact (RT) 28 J20.7 ft·lbf
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
Max Service Temperature (continuous)
Same in both: 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 250 J/g107 BTU/lb · Min Service Temperature -40°C-40 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
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 55 / 100 · Polishability 65 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 28 MJ/kg12,038 BTU/lb · Embodied Carbon (primary production) 2.1 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.
SCM432-CD vs SCM432 QT 40-45 HRC — frequently asked
Is SCM432 QT 40-45 HRC stronger than SCM432-CD?
Yes. SCM432 QT 40-45 HRC has a typical yield strength of 1,250 MPa (181 ksi) against 650 MPa (94.3 ksi) for SCM432-CD — about 92% more. Tensile strength is 1,400 MPa (203 ksi) vs 780 MPa (113 ksi).
Which condition does FabDigit quote by default, CD or QT 40-45 HRC?
QT is the default SCM432 condition in the FabDigit quote flow (neither CD nor QT 40-45 HRC). 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, SCM432-CD or SCM432 QT 40-45 HRC?
SCM432-CD. Its machinability rates good (62/100) against poor (32/100) for SCM432 QT 40-45 HRC.
Ready to make it?
Upload a CAD file and FabDigit prices the part in SCM432-CD and SCM432 QT 40-45 HRC 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.