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Steel 18NCD6-CD vs 18NCD6-N

Steel · 18NCD6 temper comparison

18NCD6-CD and 18NCD6-N are two conditions of the same steel grade, 18NCD6: CD (cold drawn) versus N (normalized). The chemistry is identical, so every difference below comes from the condition. 18NCD6-CD is the stronger of the two: yield strength 580 MPa (84.1 ksi) against 430 MPa (62.4 ksi) for 18NCD6-N, about 35% more. In exchange, 18NCD6-N is the more ductile: elongation 20% versus 12% for 18NCD6-CD.

18NCD6-CDChoose it when strength drives the design.

18NCD6-NChoose it when the part is bent, formed or impact-loaded.

18NCD6-CD vs 18NCD6-N: properties

18NCD6-CD18NCD6-N

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

700 MPa102 ksi
680 MPa98.6 ksi

Yield Strength (0.2% offset)

580 MPa84.1 ksi
430 MPa62.4 ksi

Elongation at Break

12%
20%

Reduction in Area

40%
50%

Shear Strength

425 MPa61.6 ksi
420 MPa60.9 ksi

Fatigue Strength (Endurance Limit)

300 MPa43.5 ksi
310 MPa45 ksi

Charpy V-Notch Impact (RT)

30 J22.1 ft·lbf
55 J40.6 ft·lbf

Hardness, Brinell

210 HB
200 HB

Hardness, Rockwell B

95 HRB
93 HRB

Same in both: Elastic (Young's) Modulus 207 GPa30 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,495°C2,723 °F

Thermal

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

Same in both: Thermal Conductivity 43 W/m·K24.8 BTU/hr·ft·°F · Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.6 µm/m·K6.4 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 200°C392 °F · Min Service Temperature -40°C-40 °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).

Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V · Corrosion Resistance 12 / 100

Manufacturability

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

Machinability

62 / 100
55 / 100

Machinability Rating (AISI 1212 = 100 %)

68%
60%

Weldability

40 / 100
45 / 100

Formability (cold)

40 / 100
45 / 100

Same in both: Brazeability / Solderability 60 / 100 · Polishability 65 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 29 MJ/kg12,468 BTU/lb · Embodied Carbon (primary production) 2.1 kg CO₂/kg · Embodied Water 60 L/kg7.2 gal/lb · Typical Recycled Content 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 scale18NCD6

18NCD6-CD vs 18NCD6-N — frequently asked

Is 18NCD6-CD stronger than 18NCD6-N?

Yes. 18NCD6-CD has a typical yield strength of 580 MPa (84.1 ksi) against 430 MPa (62.4 ksi) for 18NCD6-N — about 35% more. Tensile strength is 700 MPa (102 ksi) vs 680 MPa (98.6 ksi).

Which condition does FabDigit quote by default, CD or N?

A is the default 18NCD6 condition in the FabDigit quote flow (neither CD nor N). The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.

Which is easier to machine, 18NCD6-CD or 18NCD6-N?

18NCD6-CD, by a small margin. Both rate good for machinability — 62/100 against 55/100 for 18NCD6-N; for welding the order is 18NCD6-N first (fair, 45/100) then 18NCD6-CD (fair, 40/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 18NCD6-CD and 18NCD6-N 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.