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Steel 15B37-A vs 15B37-N

Steel · 15B37 temper comparison

15B37-A and 15B37-N are two conditions of the same steel grade, 15B37: A (solution annealed) versus N (normalized). The chemistry is identical, so every difference below comes from the condition. 15B37-N is the stronger of the two: yield strength 430 MPa (62.4 ksi) against 340 MPa (49.3 ksi) for 15B37-A, about 26% more; tensile strength follows at 700 MPa (102 ksi) vs 570 MPa (82.7 ksi). In exchange, 15B37-A is the more ductile: elongation 28% versus 20% for 15B37-N, and 15B37-N is harder (201 HB vs 163 HB). 15B37-N runs hotter in service (400°C vs 300°C continuous) and 15B37-N conducts electricity better (9 % IACS vs 8 % IACS).

15B37-AChoose it when the part is bent, formed or impact-loaded.

15B37-NChoose it when strength drives the design, or when the part sees heat.

15B37-A vs 15B37-N: properties

15B37-A15B37-N

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

570 MPa82.7 ksi
700 MPa102 ksi

Yield Strength (0.2% offset)

340 MPa49.3 ksi
430 MPa62.4 ksi

Elongation at Break

28%
20%

Reduction in Area

58%
45%

Shear Strength

660 MPa95.7 ksi
420 MPa60.9 ksi

Fatigue Strength (Endurance Limit)

480 MPa69.6 ksi
320 MPa46.4 ksi

Fracture Toughness (K_IC)

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

Charpy V-Notch Impact (RT)

45 J33.2 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

163 HB
201 HB

Hardness, Rockwell C

35 HRC
14 HRC

Hardness, Vickers

345 HV
211 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

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

Max Service Temperature (continuous)

300°C572 °F
400°C752 °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

8 % IACS
9 % IACS

Electrical Resistivity

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

62 / 100
55 / 100

Machinability Rating (AISI 1212 = 100 %)

70%
60%

Weldability

35 / 100
42 / 100

Formability (cold)

70 / 100
55 / 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-A vs 15B37-N — frequently asked

Is 15B37-N stronger than 15B37-A?

Yes. 15B37-N has a typical yield strength of 430 MPa (62.4 ksi) against 340 MPa (49.3 ksi) for 15B37-A — about 26% more. Tensile strength is 700 MPa (102 ksi) vs 570 MPa (82.7 ksi).

Which condition does FabDigit quote by default, A or N?

QT32-38 is the default 15B37 condition in the FabDigit quote flow (neither A nor N). 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-A or 15B37-N?

15B37-A, by a small margin. Both rate good for machinability — 62/100 against 55/100 for 15B37-N; for welding the order is 15B37-N first (fair, 42/100) then 15B37-A (fair, 35/100).

Ready to make it?

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