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Steel 30CrMo4 vs 55Cr3

Steel · grade comparison

Steel 30CrMo4 and 55Cr3 are both steel grades. 30CrMo4 is the stronger of the two: yield strength 660 MPa (95.7 ksi) against 480 MPa (69.6 ksi) for 55Cr3, about 38% more; tensile strength follows at 900 MPa (131 ksi) vs 800 MPa (116 ksi). 30CrMo4 is harder — 270 HB against 225 HB for 55Cr3 — which matters for wear surfaces and threads. 55Cr3 runs hotter in service (400°C vs 350°C continuous). On the shop floor, 30CrMo4 welds better (good vs poor), 55Cr3 forms better (45 vs 35 out of 100), and 30CrMo4 sits in a lower cost tier (budget, $) than 55Cr3 (standard, $$).

30CrMo4Choose it when strength drives the design, or when surface hardness matters.

55Cr3Choose it when the part sees heat.

30CrMo4 vs 55Cr3: properties

30CrMo455Cr3

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)

900 MPa131 ksi
800 MPa116 ksi

Yield Strength (0.2% offset)

660 MPa95.7 ksi
480 MPa69.6 ksi

Elongation at Break

15%
16%

Reduction in Area

52%
40%

Compressive Strength

710 MPa103 ksi
480 MPa69.6 ksi

Shear Strength

560 MPa81.2 ksi
500 MPa72.5 ksi

Fatigue Strength (Endurance Limit)

440 MPa63.8 ksi
360 MPa52.2 ksi

Fracture Toughness (K_IC)

90 MPa·√m81.9 ksi·√in
85 MPa·√m77.4 ksi·√in

Charpy V-Notch Impact (RT)

55 J40.6 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

270 HB
225 HB

Hardness, Rockwell C

28 HRC
20 HRC

Hardness, Vickers

285 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

1,495°C2,723 °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)

12.3 µm/m·K6.8 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)

350°C662 °F
400°C752 °F

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

Electrical

Conductivity and insulation.

Electrical Conductivity

7.5 % IACS
7.8 % IACS

Electrical Resistivity

2.3×10⁻⁷ Ω·m9.06 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
—

Corrosion Resistance

12 / 100
10 / 100

Manufacturability

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

Weldability

60 / 100
25 / 100

Formability (cold)

35 / 100
45 / 100

Castability

25 / 100
—

Brazeability / Solderability

65 / 100
40 / 100

Same in both: Machinability 50 / 100 · Machinability Rating (AISI 1212 = 100 %) 55% · Polishability 60 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

29 MJ/kg12,468 BTU/lb
26 MJ/kg11,178 BTU/lb

Embodied Carbon (primary production)

2.3 kg CO₂/kg
2 kg CO₂/kg

Embodied Water

55 L/kg6.6 gal/lb
45 L/kg5.4 gal/lb

Typical Recycled Content

25%
30%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

115 kN·m/kg
102 kN·m/kg

Specific Stiffness (E / density)

26.8 MN·m/kg
26.2 MN·m/kg

Modulus of Resilience

1,037 kJ/m³
559 kJ/m³

Thermal Diffusivity

11.6 mm²/s
12.1 mm²/s

Thermal Shock Resistance Index

15
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 scale55Cr330CrMo4

Manufacturing and finishing

Capability30CrMo455Cr3
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.

30CrMo4 vs 55Cr3 — frequently asked

Is 30CrMo4 stronger than 55Cr3?

Yes. 30CrMo4 has a typical yield strength of 660 MPa (95.7 ksi) against 480 MPa (69.6 ksi) for 55Cr3 — about 38% more. Tensile strength is 900 MPa (131 ksi) vs 800 MPa (116 ksi).

Which is cheaper, 30CrMo4 or 55Cr3?

30CrMo4 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 welds better, 30CrMo4 or 55Cr3?

30CrMo4. Its weldability rates good (60/100) against poor (25/100) for 55Cr3.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 30CrMo4 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.