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Steel SCM420 vs SNCM447

Steel · grade comparison

Steel SCM420 and SNCM447 are both steel grades. SNCM447 is the stronger of the two: yield strength 980 MPa (142 ksi) against 440 MPa (63.8 ksi) for SCM420, about 123% more; tensile strength follows at 1,100 MPa (160 ksi) vs 660 MPa (95.7 ksi). In exchange, SCM420 is the more ductile: elongation 22% versus 16% for SNCM447, and SNCM447 is harder (325 HB vs 190 HB). SCM420 conducts electricity better (7.8 % IACS vs 7 % IACS). On the shop floor, SCM420 machines more easily (good vs fair), SCM420 welds better (good vs poor), and SNCM447 sits in a lower cost tier (budget, $) than SCM420 (standard, $$).

SCM420Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

SNCM447Choose it when strength drives the design, or when cost is the deciding factor.

SCM420 vs SNCM447: properties

SCM420SNCM447

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

207 GPa30 Msi
205 GPa29.7 Msi

Tensile Strength (Ultimate)

660 MPa95.7 ksi
1,100 MPa160 ksi

Yield Strength (0.2% offset)

440 MPa63.8 ksi
980 MPa142 ksi

Elongation at Break

22%
16%

Reduction in Area

52%
48%

Shear Strength

430 MPa62.4 ksi
660 MPa95.7 ksi

Fatigue Strength (Endurance Limit)

300 MPa43.5 ksi
520 MPa75.4 ksi

Fracture Toughness (K_IC)

65 MPa·√m59.2 ksi·√in
90 MPa·√m81.9 ksi·√in

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
45 J33.2 ft·lbf

Hardness, Brinell

190 HB
325 HB

Hardness, Rockwell B

91 HRB
—

Compressive Strength

—
990 MPa144 ksi

Hardness, Rockwell C

—
34 HRC

Hardness, Vickers

—
340 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.

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

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

Min Service Temperature

-40°C-40 °F
-50°C-58 °F

Same in both: Thermal Conductivity 42 W/m·K24.3 BTU/hr·ft·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 400°C752 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

7.8 % IACS
7 % IACS

Electrical Resistivity

2.2×10⁻⁷ Ω·m8.66 µΩ·in
2.48×10⁻⁷ Ω·m9.76 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.62 V
-0.6 V

Same in both: Corrosion Resistance 12 / 100

Manufacturability

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

Machinability

60 / 100
42 / 100

Machinability Rating (AISI 1212 = 100 %)

62%
45%

Weldability

55 / 100
25 / 100

Formability (cold)

60 / 100
25 / 100

Brazeability / Solderability

65 / 100
45 / 100

Polishability

60 / 100
70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Water

55 L/kg6.6 gal/lb
60 L/kg7.2 gal/lb

Typical Recycled Content

30%
25%

Same in both: Embodied Energy (primary production) 30 MJ/kg12,898 BTU/lb · Embodied Carbon (primary production) 2.3 kg CO₂/kg

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

84 kN·m/kg
140 kN·m/kg

Specific Stiffness (E / density)

26.4 MN·m/kg
26.1 MN·m/kg

Modulus of Resilience

468 kJ/m³
2,342 kJ/m³

Thermal Diffusivity

11.4 mm²/s
11.3 mm²/s

Thermal Shock Resistance Index

11
18

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 scaleSCM420SNCM447

Manufacturing and finishing

CapabilitySCM420SNCM447
CNC machiningYes—
Sheet metalYes—
Default conditionHR—
Relative cost$$ Standard$ Budget
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.

SCM420 vs SNCM447 — frequently asked

Is SNCM447 stronger than SCM420?

Yes. SNCM447 has a typical yield strength of 980 MPa (142 ksi) against 440 MPa (63.8 ksi) for SCM420 — about 123% more. Tensile strength is 1,100 MPa (160 ksi) vs 660 MPa (95.7 ksi).

Which is cheaper, SCM420 or SNCM447?

SNCM447 is the lower-cost material: it sits in the budget tier ($) while SCM420 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 is easier to machine, SCM420 or SNCM447?

SCM420. Its machinability rates good (60/100) against fair (42/100) for SNCM447; for welding the order is SCM420 first (good, 55/100) then SNCM447 (poor, 25/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in SCM420 and SNCM447 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.