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Steel 100Cr6 vs Cronidur 30

Steel · grade comparison

Steel 100Cr6 and Cronidur 30 are both steel grades. Cronidur 30 is the stronger of the two: yield strength 1,850 MPa (268 ksi) against 420 MPa (60.9 ksi) for 100Cr6, about 4.4 times as much; tensile strength follows at 2,100 MPa (305 ksi) vs 660 MPa (95.7 ksi). In exchange, 100Cr6 is the more ductile: elongation 22% versus 4% for Cronidur 30, and Cronidur 30 is harder (680 HV vs 210 HV). Cronidur 30 runs hotter in service (250°C vs 200°C continuous) and 100Cr6 conducts heat better (45 W/m·K vs 16 W/m·K). On the shop floor, 100Cr6 machines more easily (fair vs not recommended) and 100Cr6 sits in a lower cost tier (standard, $$) than Cronidur 30 (high, $$$$).

100Cr6Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

Cronidur 30Choose it when strength drives the design, or when the part sees heat.

100Cr6 vs Cronidur 30: properties

100Cr6Cronidur 30

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

210 GPa30.5 Msi
200 GPa29 Msi

Shear Modulus

80 GPa11.6 Msi
78 GPa11.3 Msi

Bulk Modulus

160 GPa23.2 Msi
165 GPa23.9 Msi

Tensile Strength (Ultimate)

660 MPa95.7 ksi
2,100 MPa305 ksi

Yield Strength (0.2% offset)

420 MPa60.9 ksi
1,850 MPa268 ksi

Elongation at Break

22%
4%

Reduction in Area

48%
10%

Shear Strength

400 MPa58 ksi
1,300 MPa189 ksi

Fatigue Strength (Endurance Limit)

300 MPa43.5 ksi
950 MPa138 ksi

Charpy V-Notch Impact (RT)

25 J18.4 ft·lbf
10 J7.4 ft·lbf

Hardness, Brinell

200 HB
—

Hardness, Rockwell B

94 HRB
—

Hardness, Vickers

210 HV
680 HV

Compressive Strength

—
2,600 MPa377 ksi

Fracture Toughness (K_IC)

—
20 MPa·√m18.2 ksi·√in

Hardness, Rockwell C

—
59 HRC

Same in both: Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Density

7.81 g/cm³0.28 lb/in³
7.7 g/cm³0.28 lb/in³

Melting Point (Solidus)

1,424°C2,595 °F
1,400°C2,552 °F

Liquidus Temperature

1,455°C2,651 °F
1,450°C2,642 °F

Thermal

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

Thermal Conductivity

45 W/m·K26 BTU/hr·ft·°F
16 W/m·K9.2 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

11.9 µm/m·K6.6 µin/in·°F
10.5 µm/m·K5.8 µin/in·°F

Latent Heat of Fusion

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

Max Service Temperature (continuous)

200°C392 °F
250°C482 °F

Min Service Temperature

-40°C-40 °F
-253°C-423 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

8 % IACS
2.3 % IACS

Electrical Resistivity

2.2×10⁻⁷ Ω·m8.66 µΩ·in
7.5×10⁻⁷ Ω·m29.5 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.6 V
-0.2 V

Corrosion Resistance

12 / 100
58 / 100

Manufacturability

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

Machinability

45 / 100
12 / 100

Machinability Rating (AISI 1212 = 100 %)

40%
8%

Weldability

12 / 100
15 / 100

Formability (cold)

35 / 100
5 / 100

Castability

30 / 100
—

Brazeability / Solderability

45 / 100
25 / 100

Polishability

88 / 100
90 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

32 MJ/kg13,758 BTU/lb
85 MJ/kg36,543 BTU/lb

Embodied Carbon (primary production)

2.3 kg CO₂/kg
5.5 kg CO₂/kg

Embodied Water

65 L/kg7.8 gal/lb
200 L/kg24 gal/lb

Typical Recycled Content

30%
25%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

85 kN·m/kg
273 kN·m/kg

Specific Stiffness (E / density)

26.9 MN·m/kg
26 MN·m/kg

Modulus of Resilience

420 kJ/m³
8,556 kJ/m³

Thermal Diffusivity

12.3 mm²/s
4.5 mm²/s

Thermal Shock Resistance Index

12
16

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 scale100Cr6Cronidur 30

Manufacturing and finishing

Capability100Cr6Cronidur 30
CNC machiningYes—
Sheet metalYes—
Default conditionAnnealed—
Relative cost$$ Standard$$$$ High
Min. machined wall0.8 mm—
Best machined surfaceRa 1.6 µm—
AlCrNYes—
AlTiNYes—
Black OxideYes—
CVD Al2O3Yes—
CVD TiCNYes—
CVD TiNYes—
CerakoteYes—
Chrome PlatingYes—
CrNYes—
DLCYes—
E-CoatingYes—
HVOF CoatingYes—
Hot-Dip GalvanizingYes—
MoS2Yes—
Multilayer CVDYes—
Nickel PlatingYes—
PTFE CoatingYes—
PaintingYes—

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

100Cr6 vs Cronidur 30 — frequently asked

Is Cronidur 30 stronger than 100Cr6?

Yes. Cronidur 30 has a typical yield strength of 1,850 MPa (268 ksi) against 420 MPa (60.9 ksi) for 100Cr6 — about 4.4 times as much. Tensile strength is 2,100 MPa (305 ksi) vs 660 MPa (95.7 ksi).

Which is cheaper, 100Cr6 or Cronidur 30?

100Cr6 is the lower-cost material: it sits in the standard tier ($$) while Cronidur 30 is high ($$$$). 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, 100Cr6 or Cronidur 30?

100Cr6. Its machinability rates fair (45/100) against not recommended (12/100) for Cronidur 30.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 100Cr6 and Cronidur 30 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.