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Steel 15B35 vs 15MnVB

Steel · grade comparison

Steel 15B35 and 15MnVB are both steel grades. 15B35 is the stronger of the two: yield strength 620 MPa (89.9 ksi) against 390 MPa (56.6 ksi) for 15MnVB, about 59% more; tensile strength follows at 730 MPa (106 ksi) vs 620 MPa (89.9 ksi). In exchange, 15MnVB is the more ductile: elongation 22% versus 13% for 15B35, and 15B35 is harder (217 HB vs 187 HB). 15MnVB runs hotter in service (400°C vs 350°C continuous) and 15B35 conducts electricity better (9.5 % IACS vs 7.8 % IACS). On the shop floor, 15MnVB welds better (50 vs 40 out of 100).

15B35Choose it when strength drives the design.

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

15B35 vs 15MnVB: properties

15B3515MnVB

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

205 GPa29.7 Msi
210 GPa30.5 Msi

Shear Modulus

80 GPa11.6 Msi
81 GPa11.7 Msi

Tensile Strength (Ultimate)

730 MPa106 ksi
620 MPa89.9 ksi

Yield Strength (0.2% offset)

620 MPa89.9 ksi
390 MPa56.6 ksi

Elongation at Break

13%
22%

Reduction in Area

40%
55%

Compressive Strength

620 MPa89.9 ksi
—

Shear Strength

440 MPa63.8 ksi
400 MPa58 ksi

Fatigue Strength (Endurance Limit)

330 MPa47.9 ksi
285 MPa41.3 ksi

Charpy V-Notch Impact (RT)

25 J18.4 ft·lbf
70 J51.6 ft·lbf

Hardness, Brinell

217 HB
187 HB

Hardness, Rockwell B

96 HRB
91 HRB

Same in both: Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,425°C2,597 °F
1,460°C2,660 °F

Liquidus Temperature

1,495°C2,723 °F
1,510°C2,750 °F

Same in both: Density 7.85 g/cm³0.28 lb/in³

Thermal

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

Thermal Conductivity

46 W/m·K26.6 BTU/hr·ft·°F
44 W/m·K25.4 BTU/hr·ft·°F

Specific Heat Capacity

475 J/kg·K0.11 BTU/lb·°F
470 J/kg·K0.11 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

11.9 µm/m·K6.6 µin/in·°F
12.3 µm/m·K6.8 µin/in·°F

Latent Heat of Fusion

247 J/g106 BTU/lb
250 J/g107 BTU/lb

Max Service Temperature (continuous)

350°C662 °F
400°C752 °F

Min Service Temperature

-30°C-22 °F
-40°C-40 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

9.5 % IACS
7.8 % IACS

Electrical Resistivity

1.8×10⁻⁷ Ω·m7.09 µΩ·in
2.2×10⁻⁷ Ω·m8.66 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.61 V
-0.62 V

Same in both: Corrosion Resistance 10 / 100

Manufacturability

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

Machinability Rating (AISI 1212 = 100 %)

65%
60%

Weldability

40 / 100
50 / 100

Castability

—
25 / 100

Same in both: Machinability 55 / 100 · Formability (cold) 55 / 100 · Brazeability / Solderability 60 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

25 MJ/kg10,748 BTU/lb
28 MJ/kg12,038 BTU/lb

Embodied Carbon (primary production)

1.9 kg CO₂/kg
2.1 kg CO₂/kg

Embodied Water

40 L/kg4.8 gal/lb
45 L/kg5.4 gal/lb

Typical Recycled Content

30%
25%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

93 kN·m/kg
79 kN·m/kg

Specific Stiffness (E / density)

26.1 MN·m/kg
26.8 MN·m/kg

Modulus of Resilience

938 kJ/m³
362 kJ/m³

Thermal Diffusivity

12.3 mm²/s
11.9 mm²/s

Thermal Shock Resistance Index

14
11

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 scale15B3515MnVB

Manufacturing and finishing

Capability15B3515MnVB
Default condition——
Relative cost$ Budget$ Budget
Min. machined wall——
Best machined surface——

Both take the same 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.

15B35 vs 15MnVB — frequently asked

Is 15B35 stronger than 15MnVB?

Yes. 15B35 has a typical yield strength of 620 MPa (89.9 ksi) against 390 MPa (56.6 ksi) for 15MnVB — about 59% more. Tensile strength is 730 MPa (106 ksi) vs 620 MPa (89.9 ksi).

Which is cheaper, 15B35 or 15MnVB?

Both sit in the same relative cost tier ($, budget); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which welds better, 15B35 or 15MnVB?

15MnVB. Its weldability rates fair (50/100) against fair (40/100) for 15B35.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 15B35 and 15MnVB 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.