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Steel 15B62-N vs 15B62 QT 40-45 HRC

Steel · 15B62 temper comparison

15B62-N and 15B62 QT 40-45 HRC are two conditions of the same steel grade, 15B62: N (normalized) versus QT 40-45 HRC. The chemistry is identical, so every difference below comes from the condition. 15B62 QT 40-45 HRC is the stronger of the two: yield strength 1,250 MPa (181 ksi) against 570 MPa (82.7 ksi) for 15B62-N, about 119% more; tensile strength follows at 1,400 MPa (203 ksi) vs 1,000 MPa (145 ksi). 15B62 QT 40-45 HRC is harder — 400 HB against 290 HB for 15B62-N — which matters for wear surfaces and threads. On the shop floor, 15B62 QT 40-45 HRC forms better (30 vs 18 out of 100).

15B62 QT 40-45 HRCChoose it when strength drives the design, or when surface hardness matters.

15B62-N vs 15B62 QT 40-45 HRC: properties

15B62-N15B62 QT 40-45 HRC

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

1,000 MPa145 ksi
1,400 MPa203 ksi

Yield Strength (0.2% offset)

570 MPa82.7 ksi
1,250 MPa181 ksi

Elongation at Break

11%
10%

Reduction in Area

28%
38%

Shear Strength

640 MPa92.8 ksi
860 MPa125 ksi

Fatigue Strength (Endurance Limit)

440 MPa63.8 ksi
600 MPa87 ksi

Fracture Toughness (K_IC)

55 MPa·√m50.1 ksi·√in
62 MPa·√m56.4 ksi·√in

Charpy V-Notch Impact (RT)

14 J10.3 ft·lbf
20 J14.8 ft·lbf

Hardness, Brinell

290 HB
400 HB

Hardness, Rockwell B

103 HRB
100 HRB

Hardness, Vickers

305 HV
425 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 1,480°C2,696 °F

Thermal

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

Thermal Conductivity

44 W/m·K25.4 BTU/hr·ft·°F
45 W/m·K26 BTU/hr·ft·°F

Same in both: Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.5 µm/m·K6.4 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 300°C572 °F · Min Service Temperature -30°C-22 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

2.15×10⁻⁷ Ω·m8.46 µΩ·in
2.1×10⁻⁷ Ω·m8.27 µΩ·in

Same in both: Electrical Conductivity 8 % IACS

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V · Corrosion Resistance 10 / 100

Manufacturability

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

Machinability

38 / 100
42 / 100

Machinability Rating (AISI 1212 = 100 %)

50%
30%

Weldability

18 / 100
20 / 100

Formability (cold)

18 / 100
30 / 100

Same in both: Brazeability / Solderability 40 / 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 45 L/kg5.4 gal/lb · Typical Recycled Content 35%

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 scale15B62

15B62-N vs 15B62 QT 40-45 HRC — frequently asked

Is 15B62 QT 40-45 HRC stronger than 15B62-N?

Yes. 15B62 QT 40-45 HRC has a typical yield strength of 1,250 MPa (181 ksi) against 570 MPa (82.7 ksi) for 15B62-N — about 119% more. Tensile strength is 1,400 MPa (203 ksi) vs 1,000 MPa (145 ksi).

Which condition does FabDigit quote by default, N or QT 40-45 HRC?

HR is the default 15B62 condition in the FabDigit quote flow (neither N nor QT 40-45 HRC). 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.

When should I choose 15B62-N over 15B62 QT 40-45 HRC?

Pick 15B62 QT 40-45 HRC when strength drives the design, or when surface hardness matters.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 15B62-N and 15B62 QT 40-45 HRC 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.