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Steel 20MoCrS4 vs 55Cr3

Steel · grade comparison

Steel 20MoCrS4 and 55Cr3 are both steel grades. 55Cr3 is the stronger of the two: tensile strength 800 MPa (116 ksi) against 600 MPa (87 ksi) for 20MoCrS4, about 33% more. 55Cr3 is the more ductile: elongation 16% versus 10% for 20MoCrS4, and 55Cr3 is harder (225 HB vs 185 HB). 55Cr3 runs hotter in service (400°C vs 200°C continuous). On the shop floor, 20MoCrS4 machines more easily (good vs fair) and 20MoCrS4 sits in a lower cost tier (budget, $) than 55Cr3 (standard, $$).

20MoCrS4Choose it when the part is machined in volume, or when cost is the deciding factor.

55Cr3Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.

20MoCrS4 vs 55Cr3: properties

20MoCrS455Cr3

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)

600 MPa87 ksi
800 MPa116 ksi

Yield Strength (0.2% offset)

500 MPa72.5 ksi
480 MPa69.6 ksi

Elongation at Break

10%
16%

Reduction in Area

45%
40%

Compressive Strength

510 MPa74 ksi
480 MPa69.6 ksi

Shear Strength

380 MPa55.1 ksi
500 MPa72.5 ksi

Fatigue Strength (Endurance Limit)

280 MPa40.6 ksi
360 MPa52.2 ksi

Fracture Toughness (K_IC)

65 MPa·√m59.2 ksi·√in
85 MPa·√m77.4 ksi·√in

Hardness, Brinell

185 HB
225 HB

Hardness, Rockwell B

90 HRB
98 HRB

Hardness, Vickers

195 HV
236 HV

Hardness, Rockwell C

—
20 HRC

Same in both: Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Charpy V-Notch Impact (RT) 30 J22.1 ft·lbf

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.

Thermal Conductivity

42 W/m·K24.3 BTU/hr·ft·°F
44 W/m·K25.4 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

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

Latent Heat of Fusion

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

Max Service Temperature (continuous)

200°C392 °F
400°C752 °F

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

Electrical

Conductivity and insulation.

Electrical Conductivity

8 % IACS
7.8 % IACS

Same in both: 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)

-0.62 V
—

Corrosion Resistance

12 / 100
10 / 100

Manufacturability

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

Machinability

66 / 100
50 / 100

Machinability Rating (AISI 1212 = 100 %)

70%
55%

Weldability

26 / 100
25 / 100

Formability (cold)

32 / 100
45 / 100

Castability

25 / 100
—

Brazeability / Solderability

55 / 100
40 / 100

Polishability

55 / 100
60 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Carbon (primary production)

1.9 kg CO₂/kg
2 kg CO₂/kg

Embodied Water

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

Same in both: Embodied Energy (primary production) 26 MJ/kg11,178 BTU/lb · Typical Recycled Content 30%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

76 kN·m/kg
102 kN·m/kg

Specific Stiffness (E / density)

26.8 MN·m/kg
26.2 MN·m/kg

Modulus of Resilience

595 kJ/m³
559 kJ/m³

Thermal Diffusivity

11.6 mm²/s
12.1 mm²/s

Thermal Shock Resistance Index

10
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 scale55Cr320MoCrS4

Manufacturing and finishing

Capability20MoCrS455Cr3
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.

20MoCrS4 vs 55Cr3 — frequently asked

Is 55Cr3 stronger than 20MoCrS4?

Yes. 55Cr3 has a typical tensile strength of 800 MPa (116 ksi) against 600 MPa (87 ksi) for 20MoCrS4 — about 33% more.

Which is cheaper, 20MoCrS4 or 55Cr3?

20MoCrS4 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, 20MoCrS4 or 55Cr3?

20MoCrS4. Its machinability rates good (66/100) against fair (50/100) for 55Cr3.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 20MoCrS4 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.