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Steel 20KhN3A vs SCM415

Steel · grade comparison

Steel 20KhN3A and SCM415 are both steel grades. 20KhN3A is the stronger of the two: yield strength 780 MPa (113 ksi) against 430 MPa (62.4 ksi) for SCM415, about 81% more; tensile strength follows at 980 MPa (142 ksi) vs 640 MPa (92.8 ksi). In exchange, SCM415 is the more ductile: elongation 22% versus 14% for 20KhN3A, and 20KhN3A is harder (300 HB vs 180 HB). SCM415 conducts heat better (44 W/m·K vs 34 W/m·K). On the shop floor, SCM415 machines more easily (good vs fair) and SCM415 welds better (good vs poor).

20KhN3AChoose it when strength drives the design.

SCM415Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

20KhN3A vs SCM415: properties

20KhN3ASCM415

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

210 GPa30.5 Msi
206 GPa29.9 Msi

Tensile Strength (Ultimate)

980 MPa142 ksi
640 MPa92.8 ksi

Yield Strength (0.2% offset)

780 MPa113 ksi
430 MPa62.4 ksi

Elongation at Break

14%
22%

Reduction in Area

58%
55%

Compressive Strength

800 MPa116 ksi
430 MPa62.4 ksi

Shear Strength

590 MPa85.6 ksi
400 MPa58 ksi

Fatigue Strength (Endurance Limit)

470 MPa68.2 ksi
290 MPa42.1 ksi

Fracture Toughness (K_IC)

85 MPa·√m77.4 ksi·√in
90 MPa·√m81.9 ksi·√in

Charpy V-Notch Impact (RT)

62 J45.7 ft·lbf
55 J40.6 ft·lbf

Hardness, Brinell

300 HB
180 HB

Hardness, Rockwell C

31 HRC
—

Hardness, Vickers

315 HV
190 HV

Hardness, Rockwell B

—
89 HRB

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)

1,420°C2,588 °F
1,430°C2,606 °F

Liquidus Temperature

1,490°C2,714 °F
1,510°C2,750 °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 Conductivity

34 W/m·K19.6 BTU/hr·ft·°F
44 W/m·K25.4 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

11.8 µm/m·K6.6 µin/in·°F
12.3 µm/m·K6.8 µin/in·°F

Latent Heat of Fusion

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

Min Service Temperature

-60°C-76 °F
-50°C-58 °F

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

Electrical

Conductivity and insulation.

Electrical Resistivity

2.8×10⁻⁷ Ω·m11 µΩ·in
2.2×10⁻⁷ Ω·m8.66 µΩ·in

Electrical Conductivity

—
7.8 % IACS

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.6 V
-0.61 V

Corrosion Resistance

13 / 100
12 / 100

Manufacturability

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

Machinability

42 / 100
58 / 100

Machinability Rating (AISI 1212 = 100 %)

45%
60%

Weldability

28 / 100
55 / 100

Formability (cold)

30 / 100
60 / 100

Brazeability / Solderability

50 / 100
65 / 100

Polishability

62 / 100
60 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

34 MJ/kg14,617 BTU/lb
27 MJ/kg11,608 BTU/lb

Embodied Carbon (primary production)

2.6 kg CO₂/kg
2.1 kg CO₂/kg

Embodied Water

65 L/kg7.8 gal/lb
50 L/kg6 gal/lb

Same in both: Typical Recycled Content 30%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

125 kN·m/kg
82 kN·m/kg

Specific Stiffness (E / density)

26.8 MN·m/kg
26.2 MN·m/kg

Modulus of Resilience

1,449 kJ/m³
449 kJ/m³

Thermal Diffusivity

9.2 mm²/s
11.9 mm²/s

Thermal Shock Resistance Index

13
11

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 scaleSCM41520KhN3A

Manufacturing and finishing

Capability20KhN3ASCM415
CNC machining—Yes
Sheet metal—Yes
Default condition—HR
Relative cost$$ Standard$$ Standard
Min. machined wall—0.8 mm
Best machined surface—Ra 1.6 µm
AlCrN—Yes
AlTiN—Yes
Black Oxide—Yes
CVD Al2O3—Yes
CVD TiCN—Yes
CVD TiN—Yes
Cerakote—Yes
Chrome Plating—Yes
CrN—Yes
DLC—Yes
E-Coating—Yes
HVOF Coating—Yes
Hot-Dip Galvanizing—Yes
MoS2—Yes
Multilayer CVD—Yes
Nickel Plating—Yes
PTFE Coating—Yes
Painting—Yes

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

20KhN3A vs SCM415 — frequently asked

Is 20KhN3A stronger than SCM415?

Yes. 20KhN3A has a typical yield strength of 780 MPa (113 ksi) against 430 MPa (62.4 ksi) for SCM415 — about 81% more. Tensile strength is 980 MPa (142 ksi) vs 640 MPa (92.8 ksi).

Which is cheaper, 20KhN3A or SCM415?

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, 20KhN3A or SCM415?

SCM415. Its machinability rates good (58/100) against fair (42/100) for 20KhN3A; for welding the order is SCM415 first (good, 55/100) then 20KhN3A (poor, 28/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 20KhN3A and SCM415 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.