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Steel 18KhGT vs SCM415

Steel · grade comparison

Steel 18KhGT and SCM415 are both steel grades. 18KhGT is the stronger of the two: yield strength 500 MPa (72.5 ksi) against 430 MPa (62.4 ksi) for SCM415, about 16% more; tensile strength follows at 760 MPa (110 ksi) vs 640 MPa (92.8 ksi). In exchange, SCM415 is the more ductile: elongation 22% versus 18% for 18KhGT, and 18KhGT is harder (197 HB vs 180 HB). SCM415 runs hotter in service (400°C vs 350°C continuous). On the shop floor, SCM415 welds better (good vs fair) and 18KhGT sits in a lower cost tier (budget, $) than SCM415 (standard, $$).

18KhGTChoose it when strength drives the design, or when cost is the deciding factor.

SCM415Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

18KhGT vs SCM415: properties

18KhGTSCM415

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

210 GPa30.5 Msi
206 GPa29.9 Msi

Tensile Strength (Ultimate)

760 MPa110 ksi
640 MPa92.8 ksi

Yield Strength (0.2% offset)

500 MPa72.5 ksi
430 MPa62.4 ksi

Elongation at Break

18%
22%

Reduction in Area

45%
55%

Shear Strength

460 MPa66.7 ksi
400 MPa58 ksi

Fatigue Strength (Endurance Limit)

350 MPa50.8 ksi
290 MPa42.1 ksi

Charpy V-Notch Impact (RT)

70 J51.6 ft·lbf
55 J40.6 ft·lbf

Hardness, Brinell

197 HB
180 HB

Hardness, Rockwell B

92 HRB
89 HRB

Compressive Strength

—
430 MPa62.4 ksi

Fracture Toughness (K_IC)

—
90 MPa·√m81.9 ksi·√in

Hardness, Vickers

—
190 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.

Density

7.8 g/cm³0.28 lb/in³
7.85 g/cm³0.28 lb/in³

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

Thermal

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

Thermal Conductivity

41 W/m·K23.7 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)

12 µm/m·K6.7 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

Max Service Temperature (continuous)

350°C662 °F
400°C752 °F

Min Service Temperature

-40°C-40 °F
-50°C-58 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 7.8 % IACS · 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

55 / 100
58 / 100

Machinability Rating (AISI 1212 = 100 %)

55%
60%

Weldability

40 / 100
55 / 100

Formability (cold)

45 / 100
60 / 100

Brazeability / Solderability

55 / 100
65 / 100

Same in both: Polishability 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)

2.3 kg CO₂/kg
2.1 kg CO₂/kg

Embodied Water

60 L/kg7.2 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)

97 kN·m/kg
82 kN·m/kg

Specific Stiffness (E / density)

26.9 MN·m/kg
26.2 MN·m/kg

Modulus of Resilience

595 kJ/m³
449 kJ/m³

Thermal Diffusivity

11.2 mm²/s
11.9 mm²/s

Thermal Shock Resistance Index

12
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 scaleSCM41518KhGT

Manufacturing and finishing

Capability18KhGTSCM415
CNC machining—Yes
Sheet metal—Yes
Default condition—HR
Relative cost$ Budget$$ 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.

18KhGT vs SCM415 — frequently asked

Is 18KhGT stronger than SCM415?

Yes. 18KhGT has a typical yield strength of 500 MPa (72.5 ksi) against 430 MPa (62.4 ksi) for SCM415 — about 16% more. Tensile strength is 760 MPa (110 ksi) vs 640 MPa (92.8 ksi).

Which is cheaper, 18KhGT or SCM415?

18KhGT is the lower-cost material: it sits in the budget tier ($) while SCM415 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 welds better, 18KhGT or SCM415?

SCM415. Its weldability rates good (55/100) against fair (40/100) for 18KhGT.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 18KhGT 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.