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Steel Q235B-CD vs Q235B-N

Steel · Q235B temper comparison

Q235B-CD and Q235B-N are two conditions of the same steel grade, Q235B: CD (cold drawn) versus N (normalized). The chemistry is identical, so every difference below comes from the condition. Q235B-CD is the stronger of the two: yield strength 380 MPa (55.1 ksi) against 245 MPa (35.5 ksi) for Q235B-N, about 55% more; tensile strength follows at 500 MPa (72.5 ksi) vs 410 MPa (59.5 ksi). In exchange, Q235B-N is the more ductile: elongation 31% versus 15% for Q235B-CD, and Q235B-CD is harder (150 HB vs 115 HB).

Q235B-CDChoose it when strength drives the design.

Q235B-NChoose it when the part is bent, formed or impact-loaded.

Q235B-CD vs Q235B-N: properties

Q235B-CDQ235B-N

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

500 MPa72.5 ksi
410 MPa59.5 ksi

Yield Strength (0.2% offset)

380 MPa55.1 ksi
245 MPa35.5 ksi

Elongation at Break

15%
31%

Reduction in Area

55%
60%

Compressive Strength

250 MPa36.3 ksi
245 MPa35.5 ksi

Shear Strength

260 MPa37.7 ksi
255 MPa37 ksi

Fatigue Strength (Endurance Limit)

220 MPa31.9 ksi
185 MPa26.8 ksi

Fracture Toughness (K_IC)

110 MPa·√m100 ksi·√in
125 MPa·√m114 ksi·√in

Charpy V-Notch Impact (RT)

45 J33.2 ft·lbf
65 J47.9 ft·lbf

Hardness, Brinell

150 HB
115 HB

Hardness, Rockwell B

80 HRB
64 HRB

Hardness, Vickers

126 HV
121 HV

Same in both: Elastic (Young's) Modulus 206 GPa29.9 Msi · Shear Modulus 79 GPa11.5 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.3

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,495°C2,723 °F · Liquidus Temperature 1,520°C2,768 °F

Thermal

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

Thermal Conductivity

50 W/m·K28.9 BTU/hr·ft·°F
51 W/m·K29.5 BTU/hr·ft·°F

Min Service Temperature

-20°C-4 °F
-30°C-22 °F

Same in both: Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12 µm/m·K6.7 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Max Service Temperature (continuous) 350°C662 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 10.8 % IACS · Electrical Resistivity 1.6×10⁻⁷ Ω·m6.3 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.63 V · Corrosion Resistance 10 / 100

Manufacturability

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

Machinability

72 / 100
67 / 100

Machinability Rating (AISI 1212 = 100 %)

78%
72%

Weldability

90 / 100
96 / 100

Formability (cold)

55 / 100
88 / 100

Same in both: Castability 40 / 100 · Brazeability / Solderability 65 / 100 · Polishability 40 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 2 kg CO₂/kg · Embodied Water 30 L/kg3.6 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 scaleQ235B

Q235B-CD vs Q235B-N — frequently asked

Is Q235B-CD stronger than Q235B-N?

Yes. Q235B-CD has a typical yield strength of 380 MPa (55.1 ksi) against 245 MPa (35.5 ksi) for Q235B-N — about 55% more. Tensile strength is 500 MPa (72.5 ksi) vs 410 MPa (59.5 ksi).

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

HR is the default Q235B 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, Q235B-CD or Q235B-N?

Q235B-CD. Its machinability rates very good (72/100) against good (67/100) for Q235B-N; for welding the order is Q235B-N first (excellent, 96/100) then Q235B-CD (excellent, 90/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in Q235B-CD and Q235B-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.