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Steel 15B35 vs 20MnTiB

Steel · grade comparison

Steel 15B35 and 20MnTiB are both steel grades. 15B35 is the stronger of the two: yield strength 620 MPa (89.9 ksi) against 380 MPa (55.1 ksi) for 20MnTiB, about 63% more; tensile strength follows at 730 MPa (106 ksi) vs 620 MPa (89.9 ksi). In exchange, 20MnTiB is the more ductile: elongation 22% versus 13% for 15B35, and 15B35 is harder (217 HB vs 170 HB). 15B35 conducts electricity better (9.5 % IACS vs 8 % IACS).

15B35Choose it when strength drives the design.

20MnTiBChoose it when the part is bent, formed or impact-loaded.

15B35 vs 20MnTiB: properties

15B3520MnTiB

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

Bulk Modulus

160 GPa23.2 Msi
165 GPa23.9 Msi

Tensile Strength (Ultimate)

730 MPa106 ksi
620 MPa89.9 ksi

Yield Strength (0.2% offset)

620 MPa89.9 ksi
380 MPa55.1 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
280 MPa40.6 ksi

Charpy V-Notch Impact (RT)

25 J18.4 ft·lbf
70 J51.6 ft·lbf

Hardness, Brinell

217 HB
170 HB

Hardness, Rockwell B

96 HRB
87 HRB

Same in both: Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Liquidus Temperature

1,495°C2,723 °F
1,500°C2,732 °F

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °F

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 µm/m·K6.7 µin/in·°F

Latent Heat of Fusion

247 J/g106 BTU/lb
270 J/g116 BTU/lb

Min Service Temperature

-30°C-22 °F
-40°C-40 °F

Same in both: Max Service Temperature (continuous) 350°C662 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

9.5 % IACS
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

Corrosion Resistance

10 / 100
12 / 100

Manufacturability

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

Machinability Rating (AISI 1212 = 100 %)

65%
60%

Castability

—
35 / 100

Same in both: Machinability 55 / 100 · Weldability 40 / 100 · Formability (cold) 55 / 100 · Brazeability / Solderability 60 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Carbon (primary production)

1.9 kg CO₂/kg
2 kg CO₂/kg

Embodied Water

40 L/kg4.8 gal/lb
60 L/kg7.2 gal/lb

Typical Recycled Content

30%
25%

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

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
344 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 scale15B3520MnTiB

Manufacturing and finishing

Capability15B3520MnTiB
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 20MnTiB — frequently asked

Is 15B35 stronger than 20MnTiB?

Yes. 15B35 has a typical yield strength of 620 MPa (89.9 ksi) against 380 MPa (55.1 ksi) for 20MnTiB — about 63% more. Tensile strength is 730 MPa (106 ksi) vs 620 MPa (89.9 ksi).

Which is cheaper, 15B35 or 20MnTiB?

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.

When should I choose 15B35 over 20MnTiB?

Pick 15B35 when strength drives the design. Pick 20MnTiB when the part is bent, formed or impact-loaded.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 15B35 and 20MnTiB 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.