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Steel C17E2C +AC vs C17E2C +U

Steel · C17E2C temper comparison

C17E2C +AC and C17E2C +U are two conditions of the same steel grade, C17E2C: +AC (spheroidize annealed) versus +U (hot rolled). The chemistry is identical, so every difference below comes from the condition. C17E2C +U is the stronger of the two: yield strength 265 MPa (38.4 ksi) against 250 MPa (36.3 ksi) for C17E2C +AC, about 6% more; tensile strength follows at 430 MPa (62.4 ksi) vs 400 MPa (58 ksi). In exchange, C17E2C +AC is the more ductile: elongation 30% versus 26% for C17E2C +U, and C17E2C +U is harder (125 HB vs 115 HB).

C17E2C +ACChoose it when the part is bent, formed or impact-loaded.

C17E2C +UChoose it when strength drives the design.

C17E2C +AC vs C17E2C +U: properties

C17E2C +ACC17E2C +U

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

400 MPa58 ksi
430 MPa62.4 ksi

Yield Strength (0.2% offset)

250 MPa36.3 ksi
265 MPa38.4 ksi

Elongation at Break

30%
26%

Reduction in Area

68%
60%

Shear Strength

280 MPa40.6 ksi
300 MPa43.5 ksi

Fatigue Strength (Endurance Limit)

190 MPa27.6 ksi
200 MPa29 ksi

Charpy V-Notch Impact (RT)

100 J73.8 ft·lbf
80 J59 ft·lbf

Hardness, Brinell

115 HB
125 HB

Hardness, Rockwell B

64 HRB
70 HRB

Hardness, Vickers

120 HV
130 HV

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 · Compressive Strength 380 MPa55.1 ksi · Fracture Toughness (K_IC) 110 MPa·√m100 ksi·√in

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,470°C2,678 °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) 11.8 µm/m·K6.6 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -30°C-22 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 10.5 % 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

45 / 100
50 / 100

Machinability Rating (AISI 1212 = 100 %)

55%
60%

Formability (cold)

97 / 100
92 / 100

Same in both: Weldability 95 / 100 · Brazeability / Solderability 80 / 100 · Polishability 45 / 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 60 L/kg7.2 gal/lb · Typical Recycled Content 30%

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 scaleC17E2C

C17E2C +AC vs C17E2C +U — frequently asked

Is C17E2C +U stronger than C17E2C +AC?

Yes. C17E2C +U has a typical yield strength of 265 MPa (38.4 ksi) against 250 MPa (36.3 ksi) for C17E2C +AC — about 6% more. Tensile strength is 430 MPa (62.4 ksi) vs 400 MPa (58 ksi).

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

+AC+C is the default C17E2C condition in the FabDigit quote flow (neither +AC 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, C17E2C +AC or C17E2C +U?

C17E2C +U, by a small margin. Both rate fair for machinability — 50/100 against 45/100 for C17E2C +AC.

Ready to make it?

Upload a CAD file and FabDigit prices the part in C17E2C +AC and C17E2C +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.