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Steel SUM23-CD vs SUM23-HR

Steel · SUM23 temper comparison

SUM23-CD and SUM23-HR are two conditions of the same steel grade, SUM23: CD (cold drawn) versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. SUM23-CD is the stronger of the two: yield strength 415 MPa (60.2 ksi) against 250 MPa (36.3 ksi) for SUM23-HR, about 66% more; tensile strength follows at 540 MPa (78.3 ksi) vs 415 MPa (60.2 ksi). In exchange, SUM23-HR is the more ductile: elongation 22% versus 10% for SUM23-CD, and SUM23-CD is harder (167 HB vs 121 HB).

SUM23-CDChoose it when strength drives the design.

SUM23-HRChoose it when the part is bent, formed or impact-loaded.

SUM23-CD vs SUM23-HR: properties

SUM23-CDSUM23-HR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

540 MPa78.3 ksi
415 MPa60.2 ksi

Yield Strength (0.2% offset)

415 MPa60.2 ksi
250 MPa36.3 ksi

Elongation at Break

10%
22%

Reduction in Area

35%
45%

Shear Strength

330 MPa47.9 ksi
260 MPa37.7 ksi

Fatigue Strength (Endurance Limit)

230 MPa33.4 ksi
180 MPa26.1 ksi

Charpy V-Notch Impact (RT)

25 J18.4 ft·lbf
35 J25.8 ft·lbf

Hardness, Brinell

167 HB
121 HB

Hardness, Rockwell B

86 HRB
68 HRB

Same in both: Elastic (Young's) Modulus 200 GPa29 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 7.87 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,500°C2,732 °F

Thermal

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

Same in both: Thermal Conductivity 51 W/m·K29.5 BTU/hr·ft·°F · Specific Heat Capacity 486 J/kg·K0.12 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.9 µm/m·K6.6 µin/in·°F · Latent Heat of Fusion 247 J/g106 BTU/lb · Max Service Temperature (continuous) 400°C752 °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) -0.6 V · Corrosion Resistance 8 / 100

Manufacturability

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

Machinability

96 / 100
90 / 100

Machinability Rating (AISI 1212 = 100 %)

136%
125%

Formability (cold)

35 / 100
55 / 100

Same in both: Weldability 20 / 100 · Brazeability / Solderability 60 / 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) 1.9 kg CO₂/kg · Embodied Water 40 L/kg4.8 gal/lb · Typical Recycled Content 40%

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 scaleSUM23

SUM23-CD vs SUM23-HR — frequently asked

Is SUM23-CD stronger than SUM23-HR?

Yes. SUM23-CD has a typical yield strength of 415 MPa (60.2 ksi) against 250 MPa (36.3 ksi) for SUM23-HR — about 66% more. Tensile strength is 540 MPa (78.3 ksi) vs 415 MPa (60.2 ksi).

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

HR is the default SUM23 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, SUM23-CD or SUM23-HR?

SUM23-CD, by a small margin. Both rate excellent for machinability — 96/100 against 90/100 for SUM23-HR.

Ready to make it?

Upload a CAD file and FabDigit prices the part in SUM23-CD and SUM23-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.