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Steel 36MnB4 +C vs 36MnB4 +QT

Steel · 36MnB4 temper comparison

36MnB4 +C and 36MnB4 +QT are two conditions of the same steel grade, 36MnB4: +C (cold drawn) versus +QT (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. 36MnB4 +QT is the stronger of the two: yield strength 980 MPa (142 ksi) against 650 MPa (94.3 ksi) for 36MnB4 +C, about 51% more; tensile strength follows at 1,200 MPa (174 ksi) vs 780 MPa (113 ksi). 36MnB4 +QT is the more ductile: elongation 11% versus 9% for 36MnB4 +C, and 36MnB4 +QT is harder (355 HB vs 235 HB). 36MnB4 +QT runs hotter in service (350°C vs 300°C continuous). On the shop floor, 36MnB4 +C machines more easily (good vs fair) and 36MnB4 +C welds better (30 vs 20 out of 100).

36MnB4 +CChoose it when the part is machined in volume, or when it will be welded.

36MnB4 +QTChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.

36MnB4 +C vs 36MnB4 +QT: properties

36MnB4 +C36MnB4 +QT

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

780 MPa113 ksi
1,200 MPa174 ksi

Yield Strength (0.2% offset)

650 MPa94.3 ksi
980 MPa142 ksi

Elongation at Break

9%
11%

Reduction in Area

42%
45%

Compressive Strength

500 MPa72.5 ksi
1,000 MPa145 ksi

Shear Strength

400 MPa58 ksi
730 MPa106 ksi

Fatigue Strength (Endurance Limit)

350 MPa50.8 ksi
520 MPa75.4 ksi

Charpy V-Notch Impact (RT)

45 J33.2 ft·lbf
35 J25.8 ft·lbf

Hardness, Brinell

235 HB
355 HB

Hardness, Rockwell B

99 HRB
91 HRB

Hardness, Vickers

247 HV
375 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

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
350°C662 °F

Same in both: Thermal Conductivity 44 W/m·K25.4 BTU/hr·ft·°F · Specific Heat Capacity 470 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.

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) -0.62 V · Corrosion Resistance 12 / 100

Manufacturability

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

Machinability

57 / 100
38 / 100

Machinability Rating (AISI 1212 = 100 %)

62%
40%

Weldability

30 / 100
20 / 100

Formability (cold)

40 / 100
15 / 100

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

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 24 MJ/kg10,318 BTU/lb · Embodied Carbon (primary production) 1.9 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 scale36MnB4

36MnB4 +C vs 36MnB4 +QT — frequently asked

Is 36MnB4 +QT stronger than 36MnB4 +C?

Yes. 36MnB4 +QT has a typical yield strength of 980 MPa (142 ksi) against 650 MPa (94.3 ksi) for 36MnB4 +C — about 51% more. Tensile strength is 1,200 MPa (174 ksi) vs 780 MPa (113 ksi).

Which condition does FabDigit quote by default, +C or +QT?

+AC+C is the default 36MnB4 condition in the FabDigit quote flow (neither +C nor +QT). 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, 36MnB4 +C or 36MnB4 +QT?

36MnB4 +C. Its machinability rates good (57/100) against fair (38/100) for 36MnB4 +QT; for welding the order is 36MnB4 +C first (poor, 30/100) then 36MnB4 +QT (poor, 20/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 36MnB4 +C and 36MnB4 +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.