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Steel 34MnB5 vs 40CrMoV13-9

Steel · grade comparison

Steel 34MnB5 and 40CrMoV13-9 are both steel grades. 40CrMoV13-9 is the stronger of the two: yield strength 870 MPa (126 ksi) against 420 MPa (60.9 ksi) for 34MnB5, about 107% more; tensile strength follows at 1,100 MPa (160 ksi) vs 620 MPa (89.9 ksi). In exchange, 34MnB5 is the more ductile: elongation 14% versus 12% for 40CrMoV13-9, and 40CrMoV13-9 is harder (330 HB vs 185 HB). 40CrMoV13-9 runs hotter in service (500°C vs 400°C continuous) and 34MnB5 conducts heat better (44 W/m·K vs 33 W/m·K). On the shop floor, 34MnB5 machines more easily (good vs fair) and 34MnB5 welds better (good vs poor).

34MnB5Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

40CrMoV13-9Choose it when strength drives the design, or when the part sees heat.

34MnB5 vs 40CrMoV13-9: properties

34MnB540CrMoV13-9

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Shear Modulus

80 GPa11.6 Msi
81 GPa11.7 Msi

Tensile Strength (Ultimate)

620 MPa89.9 ksi
1,100 MPa160 ksi

Yield Strength (0.2% offset)

420 MPa60.9 ksi
870 MPa126 ksi

Elongation at Break

14%
12%

Shear Strength

400 MPa58 ksi
660 MPa95.7 ksi

Fatigue Strength (Endurance Limit)

280 MPa40.6 ksi
510 MPa74 ksi

Fracture Toughness (K_IC)

55 MPa·√m50.1 ksi·√in
70 MPa·√m63.7 ksi·√in

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
35 J25.8 ft·lbf

Hardness, Brinell

185 HB
330 HB

Hardness, Rockwell B

89 HRB
—

Hardness, Vickers

195 HV
345 HV

Compressive Strength

—
900 MPa131 ksi

Hardness, Rockwell C

—
33 HRC

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Reduction in Area 45%

Physical

Density and transition temperatures.

Liquidus Temperature

1,495°C2,723 °F
1,490°C2,714 °F

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F

Thermal

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

Thermal Conductivity

44 W/m·K25.4 BTU/hr·ft·°F
33 W/m·K19.1 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

12.5 µm/m·K6.9 µin/in·°F
11.8 µm/m·K6.6 µin/in·°F

Latent Heat of Fusion

250 J/g107 BTU/lb
270 J/g116 BTU/lb

Max Service Temperature (continuous)

400°C752 °F
500°C932 °F

Same in both: Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

8 % IACS
—

Electrical Resistivity

2.2×10⁻⁷ Ω·m8.66 µΩ·in
3×10⁻⁷ Ω·m11.8 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.6 V
—

Corrosion Resistance

11 / 100
15 / 100

Manufacturability

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

Machinability

55 / 100
38 / 100

Machinability Rating (AISI 1212 = 100 %)

60%
40%

Weldability

55 / 100
20 / 100

Formability (cold)

60 / 100
20 / 100

Brazeability / Solderability

45 / 100
—

Polishability

55 / 100
65 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

25 MJ/kg10,748 BTU/lb
32 MJ/kg13,758 BTU/lb

Embodied Carbon (primary production)

2 kg CO₂/kg
2.3 kg CO₂/kg

Embodied Water

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

Typical Recycled Content

25%
30%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

79 kN·m/kg
140 kN·m/kg

Modulus of Resilience

420 kJ/m³
1,802 kJ/m³

Thermal Diffusivity

11.9 mm²/s
9.1 mm²/s

Thermal Shock Resistance Index

10
15

Same in both: Specific Stiffness (E / density) 26.8 MN·m/kg

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 scale34MnB540CrMoV13-9

Manufacturing and finishing

Capability34MnB540CrMoV13-9
Sheet metalYes—
Default conditionCR—
Relative cost$$ Standard$$ Standard
Min. machined wall——
Best machined surface——
Black OxideYes—
CerakoteYes—
Chrome PlatingYes—
E-CoatingYes—
Hot-Dip GalvanizingYes—
Nickel PlatingYes—
PTFE CoatingYes—
PaintingYes—
Powder CoatingYes—
Tin PlatingYes—
Zinc PlatingYes—
Zinc-Flake (Dip-Spin) CoatingYes—
Zinc-Nickel PlatingYes—

They share 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.

34MnB5 vs 40CrMoV13-9 — frequently asked

Is 40CrMoV13-9 stronger than 34MnB5?

Yes. 40CrMoV13-9 has a typical yield strength of 870 MPa (126 ksi) against 420 MPa (60.9 ksi) for 34MnB5 — about 107% more. Tensile strength is 1,100 MPa (160 ksi) vs 620 MPa (89.9 ksi).

Which is cheaper, 34MnB5 or 40CrMoV13-9?

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

Which is easier to machine, 34MnB5 or 40CrMoV13-9?

34MnB5. Its machinability rates good (55/100) against fair (38/100) for 40CrMoV13-9; for welding the order is 34MnB5 first (good, 55/100) then 40CrMoV13-9 (poor, 20/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 34MnB5 and 40CrMoV13-9 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.