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Steel SCM422 vs SNCM431

Steel · grade comparison

Steel SCM422 and SNCM431 are both steel grades. SNCM431 is the stronger of the two: yield strength 760 MPa (110 ksi) against 370 MPa (53.7 ksi) for SCM422, about 105% more; tensile strength follows at 900 MPa (131 ksi) vs 580 MPa (84.1 ksi). In exchange, SCM422 is the more ductile: elongation 25% versus 20% for SNCM431, and SNCM431 is harder (275 HB vs 170 HB). SNCM431 runs hotter in service (400°C vs 350°C continuous).

SCM422Choose it when the part is bent, formed or impact-loaded.

SNCM431Choose it when strength drives the design, or when the part sees heat.

SCM422 vs SNCM431: properties

SCM422SNCM431

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

206 GPa29.9 Msi
205 GPa29.7 Msi

Tensile Strength (Ultimate)

580 MPa84.1 ksi
900 MPa131 ksi

Yield Strength (0.2% offset)

370 MPa53.7 ksi
760 MPa110 ksi

Elongation at Break

25%
20%

Reduction in Area

55%
58%

Shear Strength

360 MPa52.2 ksi
560 MPa81.2 ksi

Fatigue Strength (Endurance Limit)

280 MPa40.6 ksi
420 MPa60.9 ksi

Charpy V-Notch Impact (RT)

45 J33.2 ft·lbf
80 J59 ft·lbf

Hardness, Brinell

170 HB
275 HB

Hardness, Rockwell B

87 HRB
—

Compressive Strength

—
780 MPa113 ksi

Fracture Toughness (K_IC)

—
100 MPa·√m91 ksi·√in

Hardness, Rockwell C

—
28 HRC

Hardness, Vickers

—
290 HV

Same in both: Shear Modulus 80 GPa11.6 Msi · 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

1,500°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 Expansion (CTE, 20–100 °C)

12.2 µm/m·K6.8 µin/in·°F
12.3 µm/m·K6.8 µin/in·°F

Max Service Temperature (continuous)

350°C662 °F
400°C752 °F

Same in both: Thermal Conductivity 42 W/m·K24.3 BTU/hr·ft·°F · Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · 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)

-0.6 V
-0.61 V

Corrosion Resistance

10 / 100
12 / 100

Manufacturability

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

Machinability

55 / 100
50 / 100

Machinability Rating (AISI 1212 = 100 %)

60%
55%

Formability (cold)

55 / 100
30 / 100

Castability

—
25 / 100

Same in both: Weldability 40 / 100 · Brazeability / Solderability 55 / 100 · Polishability 60 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

34 MJ/kg14,617 BTU/lb
30 MJ/kg12,898 BTU/lb

Typical Recycled Content

25%
30%

Same in both: Embodied Carbon (primary production) 2.3 kg CO₂/kg · Embodied Water 60 L/kg7.2 gal/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

74 kN·m/kg
115 kN·m/kg

Specific Stiffness (E / density)

26.2 MN·m/kg
26.1 MN·m/kg

Modulus of Resilience

332 kJ/m³
1,409 kJ/m³

Thermal Shock Resistance Index

10
15

Same in both: Thermal Diffusivity 11.4 mm²/s

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 scaleSCM422SNCM431

Manufacturing and finishing

CapabilitySCM422SNCM431
Default condition——
Relative cost$ Budget$ Budget
Min. machined wall——
Best machined surface——

Both take the same 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.

SCM422 vs SNCM431 — frequently asked

Is SNCM431 stronger than SCM422?

Yes. SNCM431 has a typical yield strength of 760 MPa (110 ksi) against 370 MPa (53.7 ksi) for SCM422 — about 105% more. Tensile strength is 900 MPa (131 ksi) vs 580 MPa (84.1 ksi).

Which is cheaper, SCM422 or SNCM431?

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

Which is easier to machine, SCM422 or SNCM431?

SCM422. Its machinability rates good (55/100) against fair (50/100) for SNCM431.

Ready to make it?

Upload a CAD file and FabDigit prices the part in SCM422 and SNCM431 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.