FabDigitFabDigit

Steel 34MnB5 vs 36MnB4

Steel · grade comparison

Steel 34MnB5 and 36MnB4 are both steel grades. 36MnB4 is the stronger of the two: yield strength 500 MPa (72.5 ksi) against 420 MPa (60.9 ksi) for 34MnB5, about 19% more. In exchange, 34MnB5 is the more ductile: elongation 14% versus 12% for 36MnB4. 34MnB5 runs hotter in service (400°C vs 300°C continuous). On the shop floor, 34MnB5 welds better (good vs poor) and 36MnB4 sits in a lower cost tier (budget, $) than 34MnB5 (standard, $$).

34MnB5Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

36MnB4Choose it when strength drives the design, or when cost is the deciding factor.

34MnB5 vs 36MnB4: properties

34MnB536MnB4

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

620 MPa89.9 ksi
640 MPa92.8 ksi

Yield Strength (0.2% offset)

420 MPa60.9 ksi
500 MPa72.5 ksi

Elongation at Break

14%
12%

Reduction in Area

45%
55%

Fatigue Strength (Endurance Limit)

280 MPa40.6 ksi
300 MPa43.5 ksi

Fracture Toughness (K_IC)

55 MPa·√m50.1 ksi·√in
—

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
45 J33.2 ft·lbf

Hardness, Brinell

185 HB
190 HB

Hardness, Rockwell B

89 HRB
91 HRB

Hardness, Vickers

195 HV
200 HV

Compressive Strength

—
500 MPa72.5 ksi

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Shear Strength 400 MPa58 ksi

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 Expansion (CTE, 20–100 °C)

12.5 µm/m·K6.9 µin/in·°F
12.3 µm/m·K6.8 µin/in·°F

Max Service Temperature (continuous)

400°C752 °F
300°C572 °F

Min Service Temperature

-40°C-40 °F
-30°C-22 °F

Same in both: Thermal Conductivity 44 W/m·K25.4 BTU/hr·ft·°F · Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Latent Heat of Fusion 250 J/g107 BTU/lb

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 8 % IACS · Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.6 V
-0.62 V

Corrosion Resistance

11 / 100
12 / 100

Manufacturability

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

Weldability

55 / 100
30 / 100

Formability (cold)

60 / 100
65 / 100

Polishability

55 / 100
60 / 100

Same in both: Machinability 55 / 100 · Machinability Rating (AISI 1212 = 100 %) 60% · Brazeability / Solderability 45 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

25 MJ/kg10,748 BTU/lb
24 MJ/kg10,318 BTU/lb

Embodied Carbon (primary production)

2 kg CO₂/kg
1.9 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
82 kN·m/kg

Modulus of Resilience

420 kJ/m³
595 kJ/m³

Thermal Shock Resistance Index

10
11

Same in both: Specific Stiffness (E / density) 26.8 MN·m/kg · Thermal Diffusivity 11.9 mm²/s

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 scale34MnB536MnB4

Manufacturing and finishing

Capability34MnB536MnB4
Sheet metalYes—
Default conditionCR—
Relative cost$$ Standard$ Budget
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 36MnB4 — frequently asked

Is 36MnB4 stronger than 34MnB5?

Yes. 36MnB4 has a typical yield strength of 500 MPa (72.5 ksi) against 420 MPa (60.9 ksi) for 34MnB5 — about 19% more. Tensile strength is 640 MPa (92.8 ksi) vs 620 MPa (89.9 ksi).

Which is cheaper, 34MnB5 or 36MnB4?

36MnB4 is the lower-cost material: it sits in the budget tier ($) while 34MnB5 is standard ($$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which welds better, 34MnB5 or 36MnB4?

34MnB5. Its weldability rates good (55/100) against poor (30/100) for 36MnB4.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 34MnB5 and 36MnB4 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.