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Steel 34MnB5 vs 54SiCr6

Steel · grade comparison

Steel 34MnB5 and 54SiCr6 are both steel grades. 54SiCr6 is the stronger of the two: yield strength 1,550 MPa (225 ksi) against 420 MPa (60.9 ksi) for 34MnB5, about 3.7 times as much; tensile strength follows at 1,750 MPa (254 ksi) vs 620 MPa (89.9 ksi). In exchange, 34MnB5 is the more ductile: elongation 14% versus 7% for 54SiCr6, and 54SiCr6 is harder (470 HB vs 185 HB). 34MnB5 runs hotter in service (400°C vs 250°C continuous) and 34MnB5 conducts electricity better (8 % IACS vs 6 % IACS). On the shop floor, 34MnB5 machines more easily (good vs poor), 34MnB5 welds better (good vs poor), and 54SiCr6 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.

54SiCr6Choose it when strength drives the design, or when cost is the deciding factor.

34MnB5 vs 54SiCr6: properties

34MnB554SiCr6

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

210 GPa30.5 Msi
206 GPa29.9 Msi

Shear Modulus

80 GPa11.6 Msi
79 GPa11.5 Msi

Tensile Strength (Ultimate)

620 MPa89.9 ksi
1,750 MPa254 ksi

Yield Strength (0.2% offset)

420 MPa60.9 ksi
1,550 MPa225 ksi

Elongation at Break

14%
7%

Reduction in Area

45%
25%

Shear Strength

400 MPa58 ksi
1,050 MPa152 ksi

Fatigue Strength (Endurance Limit)

280 MPa40.6 ksi
750 MPa109 ksi

Fracture Toughness (K_IC)

55 MPa·√m50.1 ksi·√in
35 MPa·√m31.9 ksi·√in

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
14 J10.3 ft·lbf

Hardness, Brinell

185 HB
470 HB

Hardness, Rockwell B

89 HRB
—

Hardness, Vickers

195 HV
500 HV

Compressive Strength

—
1,600 MPa232 ksi

Hardness, Rockwell C

—
48 HRC

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

Physical

Density and transition temperatures.

Density

7.85 g/cm³0.28 lb/in³
7.8 g/cm³0.28 lb/in³

Liquidus Temperature

1,495°C2,723 °F
1,490°C2,714 °F

Same in both: 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
42 W/m·K24.3 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

12.5 µm/m·K6.9 µin/in·°F
11.5 µm/m·K6.4 µin/in·°F

Max Service Temperature (continuous)

400°C752 °F
250°C482 °F

Min Service Temperature

-40°C-40 °F
-50°C-58 °F

Same in both: Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Latent Heat of Fusion 250 J/g107 BTU/lb

Electrical

Conductivity and insulation.

Electrical Conductivity

8 % IACS
6 % 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).

Corrosion Resistance

11 / 100
12 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V

Manufacturability

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

Machinability

55 / 100
25 / 100

Machinability Rating (AISI 1212 = 100 %)

60%
25%

Weldability

55 / 100
15 / 100

Formability (cold)

60 / 100
10 / 100

Brazeability / Solderability

45 / 100
30 / 100

Polishability

55 / 100
60 / 100

Castability

—
30 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

25 MJ/kg10,748 BTU/lb
31 MJ/kg13,328 BTU/lb

Embodied Carbon (primary production)

2 kg CO₂/kg
2.2 kg CO₂/kg

Embodied Water

40 L/kg4.8 gal/lb
55 L/kg6.6 gal/lb

Typical Recycled Content

25%
35%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

79 kN·m/kg
224 kN·m/kg

Specific Stiffness (E / density)

26.8 MN·m/kg
26.4 MN·m/kg

Modulus of Resilience

420 kJ/m³
5,831 kJ/m³

Thermal Diffusivity

11.9 mm²/s
11.5 mm²/s

Thermal Shock Resistance Index

10
31

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 scale34MnB554SiCr6

Manufacturing and finishing

Capability34MnB554SiCr6
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 54SiCr6 — frequently asked

Is 54SiCr6 stronger than 34MnB5?

Yes. 54SiCr6 has a typical yield strength of 1,550 MPa (225 ksi) against 420 MPa (60.9 ksi) for 34MnB5 — about 3.7 times as much. Tensile strength is 1,750 MPa (254 ksi) vs 620 MPa (89.9 ksi).

Which is cheaper, 34MnB5 or 54SiCr6?

54SiCr6 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 is easier to machine, 34MnB5 or 54SiCr6?

34MnB5. Its machinability rates good (55/100) against poor (25/100) for 54SiCr6; for welding the order is 34MnB5 first (good, 55/100) then 54SiCr6 (poor, 15/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 34MnB5 and 54SiCr6 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.