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Steel C35EC +C vs C35EC +U

Steel · C35EC temper comparison

C35EC +C and C35EC +U are two conditions of the same steel grade, C35EC: +C (cold drawn) versus +U (hot rolled). The chemistry is identical, so every difference below comes from the condition. C35EC +C is the stronger of the two: yield strength 590 MPa (85.6 ksi) against 340 MPa (49.3 ksi) for C35EC +U, about 74% more; tensile strength follows at 700 MPa (102 ksi) vs 600 MPa (87 ksi). In exchange, C35EC +U is the more ductile: elongation 20% versus 9% for C35EC +C, and C35EC +C is harder (205 HB vs 170 HB). On the shop floor, C35EC +C machines more easily (68 vs 58 out of 100).

C35EC +CChoose it when strength drives the design, or when the part is machined in volume.

C35EC +UChoose it when the part is bent, formed or impact-loaded.

C35EC +C vs C35EC +U: properties

C35EC +CC35EC +U

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

700 MPa102 ksi
600 MPa87 ksi

Yield Strength (0.2% offset)

590 MPa85.6 ksi
340 MPa49.3 ksi

Elongation at Break

9%
20%

Reduction in Area

40%
45%

Compressive Strength

320 MPa46.4 ksi
350 MPa50.8 ksi

Shear Strength

330 MPa47.9 ksi
395 MPa57.3 ksi

Fatigue Strength (Endurance Limit)

300 MPa43.5 ksi
270 MPa39.2 ksi

Fracture Toughness (K_IC)

55 MPa·√m50.1 ksi·√in
50 MPa·√m45.5 ksi·√in

Charpy V-Notch Impact (RT)

55 J40.6 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

205 HB
170 HB

Hardness, Rockwell B

94 HRB
87 HRB

Hardness, Vickers

152 HV
178 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 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) 1,425°C2,597 °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 49 W/m·K28.3 BTU/hr·ft·°F · Specific Heat Capacity 480 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.1 µm/m·K6.2 µin/in·°F · Latent Heat of Fusion 250 J/g107 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) -0.61 V · Corrosion Resistance 10 / 100

Manufacturability

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

Machinability

68 / 100
58 / 100

Machinability Rating (AISI 1212 = 100 %)

70%
60%

Formability (cold)

35 / 100
50 / 100

Same in both: Weldability 55 / 100 · Castability 45 / 100 · Brazeability / Solderability 70 / 100 · Polishability 55 / 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 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 scaleC35EC

C35EC +C vs C35EC +U — frequently asked

Is C35EC +C stronger than C35EC +U?

Yes. C35EC +C has a typical yield strength of 590 MPa (85.6 ksi) against 340 MPa (49.3 ksi) for C35EC +U — about 74% more. Tensile strength is 700 MPa (102 ksi) vs 600 MPa (87 ksi).

Which condition does FabDigit quote by default, +C or +U?

+AC is the default C35EC condition in the FabDigit quote flow (neither +C nor +U). 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, C35EC +C or C35EC +U?

C35EC +C, by a small margin. Both rate good for machinability — 68/100 against 58/100 for C35EC +U.

Ready to make it?

Upload a CAD file and FabDigit prices the part in C35EC +C and C35EC +U 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.