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Steel 15B37-N vs 15B37 QT32-38

Steel · 15B37 temper comparison

15B37-N and 15B37 QT32-38 are two conditions of the same steel grade, 15B37: N (normalized) versus QT32-38 (Q&T 32–38 HRC). The chemistry is identical, so every difference below comes from the condition. 15B37 QT32-38 is the stronger of the two: yield strength 980 MPa (142 ksi) against 430 MPa (62.4 ksi) for 15B37-N, about 128% more; tensile strength follows at 1,100 MPa (160 ksi) vs 700 MPa (102 ksi). In exchange, 15B37-N is the more ductile: elongation 20% versus 14% for 15B37 QT32-38, and 15B37 QT32-38 is harder (331 HB vs 201 HB). 15B37-N runs hotter in service (400°C vs 300°C continuous) and 15B37-N conducts electricity better (9 % IACS vs 8 % IACS). On the shop floor, 15B37-N machines more easily (good vs fair).

15B37-NChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

15B37 QT32-38Choose it when strength drives the design.

15B37-N vs 15B37 QT32-38: properties

15B37-N15B37 QT32-38

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

700 MPa102 ksi
1,100 MPa160 ksi

Yield Strength (0.2% offset)

430 MPa62.4 ksi
980 MPa142 ksi

Elongation at Break

20%
14%

Reduction in Area

45%
48%

Shear Strength

420 MPa60.9 ksi
660 MPa95.7 ksi

Fatigue Strength (Endurance Limit)

320 MPa46.4 ksi
480 MPa69.6 ksi

Fracture Toughness (K_IC)

60 MPa·√m54.6 ksi·√in
70 MPa·√m63.7 ksi·√in

Charpy V-Notch Impact (RT)

30 J22.1 ft·lbf
40 J29.5 ft·lbf

Hardness, Brinell

201 HB
331 HB

Hardness, Rockwell C

14 HRC
35 HRC

Hardness, Vickers

211 HV
345 HV

Same in both: Elastic (Young's) Modulus 205 GPa29.7 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 1,495°C2,723 °F

Thermal

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

Thermal Conductivity

47 W/m·K27.2 BTU/hr·ft·°F
44 W/m·K25.4 BTU/hr·ft·°F

Max Service Temperature (continuous)

400°C752 °F
300°C572 °F

Same in both: Specific Heat Capacity 475 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.2 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.

Electrical Conductivity

9 % IACS
8 % IACS

Electrical Resistivity

1.9×10⁻⁷ Ω·m7.48 µΩ·in
2.1×10⁻⁷ Ω·m8.27 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V · Corrosion Resistance 10 / 100

Manufacturability

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

Machinability

55 / 100
45 / 100

Machinability Rating (AISI 1212 = 100 %)

60%
50%

Weldability

42 / 100
35 / 100

Formability (cold)

55 / 100
45 / 100

Same in both: Brazeability / Solderability 55 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 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 scale15B37

15B37-N vs 15B37 QT32-38 — frequently asked

Is 15B37 QT32-38 stronger than 15B37-N?

Yes. 15B37 QT32-38 has a typical yield strength of 980 MPa (142 ksi) against 430 MPa (62.4 ksi) for 15B37-N — about 128% more. Tensile strength is 1,100 MPa (160 ksi) vs 700 MPa (102 ksi).

Which condition does FabDigit quote by default, N or QT32-38?

QT32-38 is the default 15B37 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, 15B37-N or 15B37 QT32-38?

15B37-N. Its machinability rates good (55/100) against fair (45/100) for 15B37 QT32-38; for welding the order is 15B37-N first (fair, 42/100) then 15B37 QT32-38 (fair, 35/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 15B37-N and 15B37 QT32-38 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.