Steel Q235B-CD vs Q235B-HR
Steel · Q235B temper comparison
Q235B-CD and Q235B-HR are two conditions of the same steel grade, Q235B: CD (cold drawn) versus HR (hot rolled). 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 250 MPa (36.3 ksi) for Q235B-HR, about 52% more; tensile strength follows at 500 MPa (72.5 ksi) vs 420 MPa (60.9 ksi). In exchange, Q235B-HR is the more ductile: elongation 28% versus 15% for Q235B-CD, and Q235B-CD is harder (150 HB vs 120 HB).
Q235B-CDChoose it when strength drives the design.
Q235B-HRChoose it when the part is bent, formed or impact-loaded.
Q235B-CD vs Q235B-HR: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Fatigue Strength (Endurance Limit)
Hardness, Brinell
Hardness, Rockwell B
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 · Reduction in Area 55% · Compressive Strength 250 MPa36.3 ksi · Shear Strength 260 MPa37.7 ksi · Fracture Toughness (K_IC) 110 MPa·√m100 ksi·√in · Charpy V-Notch Impact (RT) 45 J33.2 ft·lbf · Hardness, Vickers 126 HV
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.
Same in both: Thermal Conductivity 50 W/m·K28.9 BTU/hr·ft·°F · 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 · Min Service Temperature -20°C-4 °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
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
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.
Q235B-CD vs Q235B-HR — frequently asked
Is Q235B-CD stronger than Q235B-HR?
Yes. Q235B-CD has a typical yield strength of 380 MPa (55.1 ksi) against 250 MPa (36.3 ksi) for Q235B-HR — about 52% more. Tensile strength is 500 MPa (72.5 ksi) vs 420 MPa (60.9 ksi).
Which condition does FabDigit quote by default, CD or HR?
HR is the default Q235B condition in the FabDigit quote flow. 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-HR?
Q235B-CD. Its machinability rates very good (72/100) against good (65/100) for Q235B-HR; for welding the order is Q235B-HR first (excellent, 95/100) then Q235B-CD (excellent, 90/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in Q235B-CD and Q235B-HR 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.