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Steel C25 +C vs C25-IH

Steel · C25 temper comparison

C25 +C and C25-IH are two conditions of the same steel grade, C25: +C (cold drawn) versus IH (induction hardened). The chemistry is identical, so every difference below comes from the condition. C25 +C is the stronger of the two: yield strength 390 MPa (56.6 ksi) against 265 MPa (38.4 ksi) for C25-IH, about 47% more; tensile strength follows at 470 MPa (68.2 ksi) vs 440 MPa (63.8 ksi). In exchange, C25-IH is the more ductile: elongation 24% versus 15% for C25 +C, and C25-IH is harder (390 HB vs 137 HB). C25 +C runs hotter in service (400°C vs 200°C continuous). On the shop floor, C25 +C machines more easily (good vs poor) and C25 +C welds better (excellent vs fair).

C25 +CChoose it when strength drives the design, or when the part sees heat.

C25-IHChoose it when the part is bent, formed or impact-loaded.

C25 +C vs C25-IH: properties

C25 +CC25-IH

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

470 MPa68.2 ksi
440 MPa63.8 ksi

Yield Strength (0.2% offset)

390 MPa56.6 ksi
265 MPa38.4 ksi

Elongation at Break

15%
24%

Reduction in Area

40%
45%

Compressive Strength

265 MPa38.4 ksi
275 MPa39.9 ksi

Shear Strength

285 MPa41.3 ksi
280 MPa40.6 ksi

Fatigue Strength (Endurance Limit)

230 MPa33.4 ksi
300 MPa43.5 ksi

Fracture Toughness (K_IC)

80 MPa·√m72.8 ksi·√in
55 MPa·√m50.1 ksi·√in

Hardness, Brinell

137 HB
390 HB

Hardness, Rockwell B

76 HRB
71 HRB

Hardness, Vickers

132 HV
412 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 · Charpy V-Notch Impact (RT) 35 J25.8 ft·lbf

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 1,515°C2,759 °F

Thermal

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

Thermal Conductivity

51 W/m·K29.5 BTU/hr·ft·°F
49 W/m·K28.3 BTU/hr·ft·°F

Max Service Temperature (continuous)

400°C752 °F
200°C392 °F

Same in both: Specific Heat Capacity 480 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.9 µm/m·K6.6 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

10 % IACS
9.5 % IACS

Electrical Resistivity

1.7×10⁻⁷ Ω·m6.69 µΩ·in
1.8×10⁻⁷ Ω·m7.09 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
25 / 100

Machinability Rating (AISI 1212 = 100 %)

70%
25%

Weldability

85 / 100
50 / 100

Formability (cold)

45 / 100
10 / 100

Same in both: Castability 30 / 100 · Brazeability / Solderability 75 / 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) 2 kg CO₂/kg · Embodied Water 40 L/kg4.8 gal/lb · Typical Recycled Content 28%

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 scaleC25

C25 +C vs C25-IH — frequently asked

Is C25 +C stronger than C25-IH?

Yes. C25 +C has a typical yield strength of 390 MPa (56.6 ksi) against 265 MPa (38.4 ksi) for C25-IH — about 47% more. Tensile strength is 470 MPa (68.2 ksi) vs 440 MPa (63.8 ksi).

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

+N is the default C25 condition in the FabDigit quote flow (neither +C nor IH). 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, C25 +C or C25-IH?

C25 +C. Its machinability rates good (68/100) against poor (25/100) for C25-IH; for welding the order is C25 +C first (excellent, 85/100) then C25-IH (fair, 50/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in C25 +C and C25-IH 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.