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Steel 34CrNiMo6-CR vs 34CrNiMo6 Q&T

Steel · 34CrNiMo6 temper comparison

34CrNiMo6-CR and 34CrNiMo6 Q&T are two conditions of the same steel grade, 34CrNiMo6: CR (cold rolled) versus Q&T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. 34CrNiMo6 Q&T is the stronger of the two: yield strength 870 MPa (126 ksi) against 780 MPa (113 ksi) for 34CrNiMo6-CR, about 12% more; tensile strength follows at 1,080 MPa (157 ksi) vs 950 MPa (138 ksi). 34CrNiMo6 Q&T is the more ductile: elongation 14% versus 8% for 34CrNiMo6-CR, and 34CrNiMo6 Q&T is harder (320 HB vs 285 HB). 34CrNiMo6 Q&T runs hotter in service (400°C vs 300°C continuous).

34CrNiMo6 Q&TChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.

34CrNiMo6-CR vs 34CrNiMo6 Q&T: properties

34CrNiMo6-CR34CrNiMo6 Q&T

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

950 MPa138 ksi
1,080 MPa157 ksi

Yield Strength (0.2% offset)

780 MPa113 ksi
870 MPa126 ksi

Elongation at Break

8%
14%

Reduction in Area

40%
52%

Compressive Strength

780 MPa113 ksi
870 MPa126 ksi

Shear Strength

570 MPa82.7 ksi
650 MPa94.3 ksi

Fatigue Strength (Endurance Limit)

430 MPa62.4 ksi
500 MPa72.5 ksi

Charpy V-Notch Impact (RT)

30 J22.1 ft·lbf
60 J44.3 ft·lbf

Hardness, Brinell

285 HB
320 HB

Hardness, Rockwell C

30 HRC
34 HRC

Hardness, Vickers

300 HV
335 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Fracture Toughness (K_IC) 90 MPa·√m81.9 ksi·√in

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 1,490°C2,714 °F

Thermal

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

Max Service Temperature (continuous)

300°C572 °F
400°C752 °F

Same in both: Thermal Conductivity 42 W/m·K24.3 BTU/hr·ft·°F · Specific Heat Capacity 465 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.

Same in both: Electrical Conductivity 7.5 % IACS · Electrical Resistivity 2.3×10⁻⁷ Ω·m9.06 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%

Formability (cold)

25 / 100
30 / 100

Same in both: Weldability 30 / 100 · Brazeability / Solderability 50 / 100 · Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 32 MJ/kg13,758 BTU/lb · Embodied Carbon (primary production) 2.3 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 scale34CrNiMo6

34CrNiMo6-CR vs 34CrNiMo6 Q&T — frequently asked

Is 34CrNiMo6 Q&T stronger than 34CrNiMo6-CR?

Yes. 34CrNiMo6 Q&T has a typical yield strength of 870 MPa (126 ksi) against 780 MPa (113 ksi) for 34CrNiMo6-CR — about 12% more. Tensile strength is 1,080 MPa (157 ksi) vs 950 MPa (138 ksi).

Which condition does FabDigit quote by default, CR or Q&T?

HR is the default 34CrNiMo6 condition in the FabDigit quote flow (neither CR nor Q&T). 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, 34CrNiMo6-CR or 34CrNiMo6 Q&T?

34CrNiMo6-CR, by a small margin. Both rate fair for machinability — 50/100 against 42/100 for 34CrNiMo6 Q&T.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 34CrNiMo6-CR and 34CrNiMo6 Q&T 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.