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Steel 17CrNiMo6 vs 5120

Steel · grade comparison

Steel 17CrNiMo6 and 5120 are both steel grades, both case hardening steel. 17CrNiMo6 is the stronger of the two: yield strength 430 MPa (62.4 ksi) against 295 MPa (42.8 ksi) for 5120, about 46% more; tensile strength follows at 700 MPa (102 ksi) vs 470 MPa (68.2 ksi). In exchange, 5120 is the more ductile: elongation 25% versus 20% for 17CrNiMo6, and 17CrNiMo6 is harder (200 HB vs 145 HB). 5120 runs hotter in service (350°C vs 300°C continuous) and 5120 conducts heat better (46 W/m·K vs 38 W/m·K). On the shop floor, 5120 machines more easily (good vs fair) and 5120 welds better (good vs poor).

17CrNiMo6Choose it when strength drives the design.

5120Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

17CrNiMo6 vs 5120: properties

17CrNiMo65120

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

210 GPa30.5 Msi
205 GPa29.7 Msi

Tensile Strength (Ultimate)

700 MPa102 ksi
470 MPa68.2 ksi

Yield Strength (0.2% offset)

430 MPa62.4 ksi
295 MPa42.8 ksi

Elongation at Break

20%
25%

Shear Strength

430 MPa62.4 ksi
300 MPa43.5 ksi

Fatigue Strength (Endurance Limit)

320 MPa46.4 ksi
235 MPa34.1 ksi

Charpy V-Notch Impact (RT)

65 J47.9 ft·lbf
60 J44.3 ft·lbf

Hardness, Brinell

200 HB
145 HB

Hardness, Rockwell B

93 HRB
78 HRB

Hardness, Vickers

210 HV
152 HV

Compressive Strength

—
295 MPa42.8 ksi

Fracture Toughness (K_IC)

—
90 MPa·√m81.9 ksi·√in

Same in both: Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Reduction in Area 55%

Physical

Density and transition temperatures.

Liquidus Temperature

1,490°C2,714 °F
1,500°C2,732 °F

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F

Thermal

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

Thermal Conductivity

38 W/m·K22 BTU/hr·ft·°F
46 W/m·K26.6 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

11.5 µm/m·K6.4 µin/in·°F
11.9 µm/m·K6.6 µin/in·°F

Max Service Temperature (continuous)

300°C572 °F
350°C662 °F

Min Service Temperature

-40°C-40 °F
-30°C-22 °F

Same in both: Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Latent Heat of Fusion 270 J/g116 BTU/lb

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)

-0.6 V
-0.61 V

Same in both: Corrosion Resistance 12 / 100

Manufacturability

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

Machinability

50 / 100
62 / 100

Machinability Rating (AISI 1212 = 100 %)

55%
65%

Weldability

30 / 100
60 / 100

Formability (cold)

40 / 100
58 / 100

Castability

25 / 100
—

Brazeability / Solderability

45 / 100
70 / 100

Polishability

65 / 100
55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

32 MJ/kg13,758 BTU/lb
25 MJ/kg10,748 BTU/lb

Embodied Carbon (primary production)

2.3 kg CO₂/kg
1.9 kg CO₂/kg

Embodied Water

55 L/kg6.6 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)

89 kN·m/kg
60 kN·m/kg

Specific Stiffness (E / density)

26.8 MN·m/kg
26.1 MN·m/kg

Modulus of Resilience

440 kJ/m³
212 kJ/m³

Thermal Diffusivity

10.3 mm²/s
12.5 mm²/s

Thermal Shock Resistance Index

11
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 scale512017CrNiMo6

Manufacturing and finishing

Capability17CrNiMo65120
Default conditionAnnealedHR
Relative cost$$ Standard$$ Standard
Min. machined wall0.8 mm0.8 mm
Best machined surfaceRa 1.6 µmRa 1.6 µm

Both are offered for CNC machining and Sheet metal. Both take the same 38 finishes: AlCrN, AlTiN, Black Oxide, CVD Al2O3, CVD TiCN, CVD TiN, Cerakote, Chrome Plating, Copper Plating, CrN, DLC, E-Coating and 26 more.

17CrNiMo6 vs 5120 — frequently asked

Is 17CrNiMo6 stronger than 5120?

Yes. 17CrNiMo6 has a typical yield strength of 430 MPa (62.4 ksi) against 295 MPa (42.8 ksi) for 5120 — about 46% more. Tensile strength is 700 MPa (102 ksi) vs 470 MPa (68.2 ksi).

Which is cheaper, 17CrNiMo6 or 5120?

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

Which is easier to machine, 17CrNiMo6 or 5120?

5120. Its machinability rates good (62/100) against fair (50/100) for 17CrNiMo6; for welding the order is 5120 first (good, 60/100) then 17CrNiMo6 (poor, 30/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 17CrNiMo6 and 5120 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.