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Steel 1075 vs 18Ni(400)

Steel · grade comparison

Steel 1075 and 18Ni(400) are both steel grades. 18Ni(400) is the stronger of the two: yield strength 2,680 MPa (389 ksi) against 470 MPa (68.2 ksi) for 1075, about 5.7 times as much; tensile strength follows at 2,760 MPa (400 ksi) vs 830 MPa (120 ksi). In exchange, 1075 is the more ductile: elongation 11% versus 6% for 18Ni(400), and 18Ni(400) is harder (655 HV vs 247 HV). 1075 is lighter (7.85 g/cm³ vs 8.1 g/cm³ for 18Ni(400)) and 18Ni(400) runs hotter in service (400°C vs 300°C continuous). On the shop floor, 1075 machines more easily (fair vs poor), 18Ni(400) welds better (very good vs poor), and 1075 sits in a lower cost tier (standard, $$) than 18Ni(400) (high, $$$$).

1075Choose it when the part is bent, formed or impact-loaded, or when weight is the constraint.

18Ni(400)Choose it when strength drives the design, or when the part sees heat.

1075 vs 18Ni(400): properties

107518Ni(400)

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

205 GPa29.7 Msi
200 GPa29 Msi

Shear Modulus

80 GPa11.6 Msi
77 GPa11.2 Msi

Bulk Modulus

160 GPa23.2 Msi
165 GPa23.9 Msi

Poisson's Ratio

0.29
0.3

Tensile Strength (Ultimate)

830 MPa120 ksi
2,760 MPa400 ksi

Yield Strength (0.2% offset)

470 MPa68.2 ksi
2,680 MPa389 ksi

Elongation at Break

11%
6%

Reduction in Area

20%
28%

Shear Strength

520 MPa75.4 ksi
1,650 MPa239 ksi

Fatigue Strength (Endurance Limit)

370 MPa53.7 ksi
800 MPa116 ksi

Charpy V-Notch Impact (RT)

9 J6.6 ft·lbf
8 J5.9 ft·lbf

Hardness, Brinell

235 HB
—

Hardness, Rockwell B

99 HRB
—

Hardness, Vickers

247 HV
655 HV

Compressive Strength

—
2,800 MPa406 ksi

Fracture Toughness (K_IC)

—
30 MPa·√m27.3 ksi·√in

Hardness, Rockwell C

—
58 HRC

Physical

Density and transition temperatures.

Density

7.85 g/cm³0.28 lb/in³
8.1 g/cm³0.29 lb/in³

Melting Point (Solidus)

1,425°C2,597 °F
1,400°C2,552 °F

Liquidus Temperature

1,470°C2,678 °F
1,440°C2,624 °F

Thermal

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

Thermal Conductivity

48 W/m·K27.7 BTU/hr·ft·°F
18 W/m·K10.4 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

11.5 µm/m·K6.4 µin/in·°F
10.1 µm/m·K5.6 µin/in·°F

Latent Heat of Fusion

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

Max Service Temperature (continuous)

300°C572 °F
400°C752 °F

Min Service Temperature

-30°C-22 °F
-73°C-99 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

9.5 % IACS
2.6 % IACS

Electrical Resistivity

1.8×10⁻⁷ Ω·m7.09 µΩ·in
6.6×10⁻⁷ Ω·m26 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.65 V
-0.55 V

Corrosion Resistance

8 / 100
25 / 100

Manufacturability

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

Machinability

38 / 100
18 / 100

Machinability Rating (AISI 1212 = 100 %)

40%
20%

Weldability

18 / 100
70 / 100

Formability (cold)

35 / 100
5 / 100

Castability

40 / 100
—

Brazeability / Solderability

45 / 100
35 / 100

Polishability

70 / 100
80 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

25 MJ/kg10,748 BTU/lb
90 MJ/kg38,693 BTU/lb

Embodied Carbon (primary production)

1.9 kg CO₂/kg
6.5 kg CO₂/kg

Embodied Water

40 L/kg4.8 gal/lb
110 L/kg13.2 gal/lb

Typical Recycled Content

28%
20%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

106 kN·m/kg
341 kN·m/kg

Specific Stiffness (E / density)

26.1 MN·m/kg
24.7 MN·m/kg

Modulus of Resilience

539 kJ/m³
17,956 kJ/m³

Thermal Diffusivity

12.9 mm²/s
4.9 mm²/s

Thermal Shock Resistance Index

17
25

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 scale107518Ni(400)

Manufacturing and finishing

Capability107518Ni(400)
CNC machiningYes—
Sheet metalYes—
Default conditionHR—
Relative cost$$ Standard$$$$ High
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.

1075 vs 18Ni(400) — frequently asked

Is 18Ni(400) stronger than 1075?

Yes. 18Ni(400) has a typical yield strength of 2,680 MPa (389 ksi) against 470 MPa (68.2 ksi) for 1075 — about 5.7 times as much. Tensile strength is 2,760 MPa (400 ksi) vs 830 MPa (120 ksi).

Which is cheaper, 1075 or 18Ni(400)?

1075 is the lower-cost material: it sits in the standard tier ($$) while 18Ni(400) is high ($$$$). 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, 1075 or 18Ni(400)?

1075. Its machinability rates fair (38/100) against poor (18/100) for 18Ni(400); for welding the order is 18Ni(400) first (very good, 70/100) then 1075 (poor, 18/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 1075 and 18Ni(400) 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.