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Steel 23MnB3 vs 55Cr3

Steel · grade comparison

Steel 23MnB3 and 55Cr3 are both steel grades. 23MnB3 is the stronger of the two: yield strength 920 MPa (133 ksi) against 480 MPa (69.6 ksi) for 55Cr3, about 92% more; tensile strength follows at 1,050 MPa (152 ksi) vs 800 MPa (116 ksi). In exchange, 55Cr3 is the more ductile: elongation 16% versus 13% for 23MnB3, and 23MnB3 is harder (320 HB vs 225 HB). 55Cr3 runs hotter in service (400°C vs 350°C continuous). On the shop floor, 23MnB3 welds better (fair vs poor) and 23MnB3 sits in a lower cost tier (budget, $) than 55Cr3 (standard, $$).

23MnB3Choose it when strength drives the design, or when it will be welded.

55Cr3Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

23MnB3 vs 55Cr3: properties

23MnB355Cr3

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
79.5 GPa11.5 Msi

Tensile Strength (Ultimate)

1,050 MPa152 ksi
800 MPa116 ksi

Yield Strength (0.2% offset)

920 MPa133 ksi
480 MPa69.6 ksi

Elongation at Break

13%
16%

Reduction in Area

52%
40%

Compressive Strength

950 MPa138 ksi
480 MPa69.6 ksi

Shear Strength

640 MPa92.8 ksi
500 MPa72.5 ksi

Fatigue Strength (Endurance Limit)

480 MPa69.6 ksi
360 MPa52.2 ksi

Fracture Toughness (K_IC)

70 MPa·√m63.7 ksi·√in
85 MPa·√m77.4 ksi·√in

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

320 HB
225 HB

Hardness, Rockwell C

34 HRC
20 HRC

Hardness, Vickers

335 HV
236 HV

Hardness, Rockwell B

—
98 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
1,420°C2,588 °F

Liquidus Temperature

1,500°C2,732 °F
1,490°C2,714 °F

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

Thermal

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

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

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

Max Service Temperature (continuous)

350°C662 °F
400°C752 °F

Same in both: Thermal Conductivity 44 W/m·K25.4 BTU/hr·ft·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

8.6 % IACS
7.8 % IACS

Electrical Resistivity

2×10⁻⁷ Ω·m7.87 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)

-0.6 V
—

Same in both: Corrosion Resistance 10 / 100

Manufacturability

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

Machinability

42 / 100
50 / 100

Machinability Rating (AISI 1212 = 100 %)

45%
55%

Weldability

40 / 100
25 / 100

Formability (cold)

30 / 100
45 / 100

Brazeability / Solderability

55 / 100
40 / 100

Same in both: Polishability 60 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

30 MJ/kg12,898 BTU/lb
26 MJ/kg11,178 BTU/lb

Embodied Carbon (primary production)

2.2 kg CO₂/kg
2 kg CO₂/kg

Embodied Water

60 L/kg7.2 gal/lb
45 L/kg5.4 gal/lb

Same in both: Typical Recycled Content 30%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

134 kN·m/kg
102 kN·m/kg

Specific Stiffness (E / density)

26.8 MN·m/kg
26.2 MN·m/kg

Modulus of Resilience

2,015 kJ/m³
559 kJ/m³

Thermal Diffusivity

11.9 mm²/s
12.1 mm²/s

Thermal Shock Resistance Index

18
14

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 scale55Cr323MnB3

Manufacturing and finishing

Capability23MnB355Cr3
CNC machining—Yes
Sheet metal—Yes
Default condition—Annealed
Relative cost$ Budget$$ Standard
Min. machined wall—0.8 mm
Best machined surface—Ra 1.6 µm
AlCrN—Yes
AlTiN—Yes
Black Oxide—Yes
CVD Al2O3—Yes
CVD TiCN—Yes
CVD TiN—Yes
Cerakote—Yes
Chrome Plating—Yes
CrN—Yes
DLC—Yes
E-Coating—Yes
HVOF Coating—Yes
Hot-Dip Galvanizing—Yes
MoS2—Yes
Multilayer CVD—Yes
Nickel Plating—Yes
PTFE Coating—Yes
Painting—Yes

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

23MnB3 vs 55Cr3 — frequently asked

Is 23MnB3 stronger than 55Cr3?

Yes. 23MnB3 has a typical yield strength of 920 MPa (133 ksi) against 480 MPa (69.6 ksi) for 55Cr3 — about 92% more. Tensile strength is 1,050 MPa (152 ksi) vs 800 MPa (116 ksi).

Which is cheaper, 23MnB3 or 55Cr3?

23MnB3 is the lower-cost material: it sits in the budget tier ($) while 55Cr3 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, 23MnB3 or 55Cr3?

55Cr3, by a small margin. Both rate fair for machinability — 50/100 against 42/100 for 23MnB3; for welding the order is 23MnB3 first (fair, 40/100) then 55Cr3 (poor, 25/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 23MnB3 and 55Cr3 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.