Steel 20Cr2Ni4-CD vs 20Cr2Ni4 QT-30-34HRC
Steel · 20Cr2Ni4 temper comparison
20Cr2Ni4-CD and 20Cr2Ni4 QT-30-34HRC are two conditions of the same steel grade, 20Cr2Ni4: CD (cold drawn) versus QT-30-34HRC. The chemistry is identical, so every difference below comes from the condition. 20Cr2Ni4 QT-30-34HRC is the stronger of the two: yield strength 860 MPa (125 ksi) against 800 MPa (116 ksi) for 20Cr2Ni4-CD, about 8% more; tensile strength follows at 1,000 MPa (145 ksi) vs 950 MPa (138 ksi). 20Cr2Ni4 QT-30-34HRC is the more ductile: elongation 16% versus 11% for 20Cr2Ni4-CD, and 20Cr2Ni4 QT-30-34HRC is harder (302 HB vs 275 HB). 20Cr2Ni4 QT-30-34HRC runs hotter in service (450°C vs 350°C continuous). On the shop floor, 20Cr2Ni4-CD machines more easily (fair vs poor).
20Cr2Ni4-CDChoose it when the part is machined in volume.
20Cr2Ni4 QT-30-34HRCChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.
20Cr2Ni4-CD vs 20Cr2Ni4 QT-30-34HRC: 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.
20Cr2Ni4-CD20Cr2Ni4 QT-30-34HRC
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)
Charpy V-Notch Impact (RT)
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 165 GPa23.9 Msi · Poisson's Ratio 0.29 · Shear Strength 590 MPa85.6 ksi
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 1,490°C2,714 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 33 W/m·K19.1 BTU/hr·ft·°F · Specific Heat Capacity 465 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.6 µm/m·K6.4 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -60°C-76 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Resistivity 2.6×10⁻⁷ Ω·m10.2 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) 36 MJ/kg15,477 BTU/lb · Embodied Carbon (primary production) 2.7 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.
20Cr2Ni4-CD vs 20Cr2Ni4 QT-30-34HRC — frequently asked
Is 20Cr2Ni4 QT-30-34HRC stronger than 20Cr2Ni4-CD?
Yes. 20Cr2Ni4 QT-30-34HRC has a typical yield strength of 860 MPa (125 ksi) against 800 MPa (116 ksi) for 20Cr2Ni4-CD — about 8% more. Tensile strength is 1,000 MPa (145 ksi) vs 950 MPa (138 ksi).
Which condition does FabDigit quote by default, CD or QT-30-34HRC?
A is the default 20Cr2Ni4 condition in the FabDigit quote flow (neither CD nor QT-30-34HRC). 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, 20Cr2Ni4-CD or 20Cr2Ni4 QT-30-34HRC?
20Cr2Ni4-CD. Its machinability rates fair (46/100) against poor (34/100) for 20Cr2Ni4 QT-30-34HRC.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 20Cr2Ni4-CD and 20Cr2Ni4 QT-30-34HRC 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.