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Steel 36CrB4 +H vs 36CrB4 +QT

Steel · 36CrB4 temper comparison

36CrB4 +H and 36CrB4 +QT are two conditions of the same steel grade, 36CrB4: +H (supplied with specified hardenability (Jominy band), for hardening) versus +QT (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. 36CrB4 +QT is the stronger of the two: yield strength 850 MPa (123 ksi) against 400 MPa (58 ksi) for 36CrB4 +H, about 113% more; tensile strength follows at 1,050 MPa (152 ksi) vs 620 MPa (89.9 ksi). In exchange, 36CrB4 +H is the more ductile: elongation 20% versus 13% for 36CrB4 +QT, and 36CrB4 +QT is harder (320 HB vs 190 HB). 36CrB4 +QT runs hotter in service (300°C vs 180°C continuous). On the shop floor, 36CrB4 +H machines more easily (good vs fair) and 36CrB4 +H welds better (fair vs poor).

36CrB4 +HChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

36CrB4 +QTChoose it when strength drives the design, or when the part sees heat.

36CrB4 +H vs 36CrB4 +QT: properties

36CrB4 +H36CrB4 +QT

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

620 MPa89.9 ksi
1,050 MPa152 ksi

Yield Strength (0.2% offset)

400 MPa58 ksi
850 MPa123 ksi

Elongation at Break

20%
13%

Reduction in Area

48%
50%

Compressive Strength

410 MPa59.5 ksi
860 MPa125 ksi

Shear Strength

380 MPa55.1 ksi
630 MPa91.4 ksi

Fatigue Strength (Endurance Limit)

280 MPa40.6 ksi
470 MPa68.2 ksi

Charpy V-Notch Impact (RT)

15 J11.1 ft·lbf
40 J29.5 ft·lbf

Hardness, Brinell

190 HB
320 HB

Hardness, Rockwell C

54 HRC
33 HRC

Hardness, Vickers

200 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) 60 MPa·√m54.6 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 1,500°C2,732 °F

Thermal

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

Thermal Conductivity

45 W/m·K26 BTU/hr·ft·°F
43 W/m·K24.8 BTU/hr·ft·°F

Max Service Temperature (continuous)

180°C356 °F
300°C572 °F

Same in both: Specific Heat Capacity 460 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

8 % IACS
7.8 % IACS

Electrical Resistivity

2.15×10⁻⁷ Ω·m8.46 µΩ·in
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 11 / 100

Manufacturability

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

Machinability

58 / 100
45 / 100

Machinability Rating (AISI 1212 = 100 %)

58%
45%

Weldability

45 / 100
30 / 100

Formability (cold)

45 / 100
20 / 100

Same in both: Castability 30 / 100 · Brazeability / Solderability 50 / 100 · Polishability 60 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 29 MJ/kg12,468 BTU/lb · Embodied Carbon (primary production) 2.1 kg CO₂/kg · Embodied Water 55 L/kg6.6 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 scale36CrB4

36CrB4 +H vs 36CrB4 +QT — frequently asked

Is 36CrB4 +QT stronger than 36CrB4 +H?

Yes. 36CrB4 +QT has a typical yield strength of 850 MPa (123 ksi) against 400 MPa (58 ksi) for 36CrB4 +H — about 113% more. Tensile strength is 1,050 MPa (152 ksi) vs 620 MPa (89.9 ksi).

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

+QT is the default 36CrB4 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, 36CrB4 +H or 36CrB4 +QT?

36CrB4 +H. Its machinability rates good (58/100) against fair (45/100) for 36CrB4 +QT; for welding the order is 36CrB4 +H first (fair, 45/100) then 36CrB4 +QT (poor, 30/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 36CrB4 +H and 36CrB4 +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.