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Steel 52100 vs 9Cr18

Steel · grade comparison

Steel 52100 and 9Cr18 are both steel grades. 9Cr18 is the stronger of the two: yield strength 450 MPa (65.3 ksi) against 415 MPa (60.2 ksi) for 52100, about 8% more; tensile strength follows at 760 MPa (110 ksi) vs 690 MPa (100 ksi). In exchange, 52100 is the more ductile: elongation 25% versus 18% for 9Cr18, and 9Cr18 is harder (225 HB vs 195 HB). 52100 conducts heat better (46 W/m·K vs 24 W/m·K).

52100Choose it when the part is bent, formed or impact-loaded.

9Cr18Choose it when strength drives the design.

52100 vs 9Cr18: properties

521009Cr18

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

205 GPa29.7 Msi
200 GPa29 Msi

Shear Modulus

80 GPa11.6 Msi
78 GPa11.3 Msi

Bulk Modulus

166 GPa24.1 Msi
160 GPa23.2 Msi

Poisson's Ratio

0.3
0.28

Tensile Strength (Ultimate)

690 MPa100 ksi
760 MPa110 ksi

Yield Strength (0.2% offset)

415 MPa60.2 ksi
450 MPa65.3 ksi

Elongation at Break

25%
18%

Reduction in Area

45%
40%

Compressive Strength

430 MPa62.4 ksi
480 MPa69.6 ksi

Shear Strength

420 MPa60.9 ksi
470 MPa68.2 ksi

Fatigue Strength (Endurance Limit)

320 MPa46.4 ksi
350 MPa50.8 ksi

Hardness, Brinell

195 HB
225 HB

Hardness, Rockwell B

93 HRB
97 HRB

Hardness, Vickers

205 HV
235 HV

Same in both: Charpy V-Notch Impact (RT) 15 J11.1 ft·lbf

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
1,370°C2,498 °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

46 W/m·K26.6 BTU/hr·ft·°F
24 W/m·K13.9 BTU/hr·ft·°F

Specific Heat Capacity

475 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
10.4 µm/m·K5.8 µin/in·°F

Latent Heat of Fusion

247 J/g106 BTU/lb
270 J/g116 BTU/lb

Min Service Temperature

-40°C-40 °F
-50°C-58 °F

Same in both: Max Service Temperature (continuous) 400°C752 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

7 % IACS
2.9 % IACS

Electrical Resistivity

2.5×10⁻⁷ Ω·m9.84 µΩ·in
6×10⁻⁷ Ω·m23.6 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.62 V
-0.25 V

Corrosion Resistance

12 / 100
38 / 100

Manufacturability

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

Machinability

40 / 100
45 / 100

Machinability Rating (AISI 1212 = 100 %)

40%
45%

Weldability

12 / 100
20 / 100

Formability (cold)

35 / 100
30 / 100

Castability

25 / 100
30 / 100

Brazeability / Solderability

35 / 100
45 / 100

Polishability

85 / 100
60 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

30 MJ/kg12,898 BTU/lb
50 MJ/kg21,496 BTU/lb

Embodied Carbon (primary production)

2.2 kg CO₂/kg
3.4 kg CO₂/kg

Embodied Water

55 L/kg6.6 gal/lb
100 L/kg12 gal/lb

Typical Recycled Content

30%
40%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

88 kN·m/kg
99 kN·m/kg

Specific Stiffness (E / density)

26.2 MN·m/kg
26 MN·m/kg

Modulus of Resilience

420 kJ/m³
506 kJ/m³

Thermal Diffusivity

12.4 mm²/s
6.8 mm²/s

Thermal Shock Resistance Index

13
9

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 scale521009Cr18

Manufacturing and finishing

Capability521009Cr18
CNC machiningYes—
Sheet metalYes—
Default conditionAnnealed—
Relative cost$$$ Premium$$$ Premium
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.

52100 vs 9Cr18 — frequently asked

Is 9Cr18 stronger than 52100?

Yes. 9Cr18 has a typical yield strength of 450 MPa (65.3 ksi) against 415 MPa (60.2 ksi) for 52100 — about 8% more. Tensile strength is 760 MPa (110 ksi) vs 690 MPa (100 ksi).

Which is cheaper, 52100 or 9Cr18?

Both sit in the same relative cost tier ($$$, premium); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which is easier to machine, 52100 or 9Cr18?

9Cr18, by a small margin. Both rate fair for machinability — 45/100 against 40/100 for 52100; for welding the order is 9Cr18 first (poor, 20/100) then 52100 (not recommended, 12/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 52100 and 9Cr18 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.