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Steel C15E +C (Cold drawn)

Supply condition

EN C15E

Pick for close tolerance, straight bright bar with higher yield strength and better chip control than hot rolled.

Budget cost $

Values for the +C condition

Other C15E tempers and conditions

C15E is listed in 8 conditions; see the grade overview at C15E.

Compare all 8 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
Hot rolled
Cheapest bar/plate condition for non-critical welded structures and parts that will be heat treated later.23038028111 HB—
Annealed
Choose for maximum cold formability — deep drawing, cold heading, severe upsetting before carburizing.28538537111 HB—
+NDefault
Normalized
Standard stocked bar condition: uniform fine grain, good toughness and machining behaviour before carburizing or welding.32542535121 HB—
Stress relieved
Use when drawn bar must stay straight after heavy asymmetric machining or subsequent heat treatment.33041021120 HB10.8 % IACS
Cold rolled sheet/strip
Sheet-metal condition for stamped, bent and welded parts needing a smooth surface ready for plating or paint.35045020130 HB10.7 % IACS
+CThis page
Cold drawn
Pick for close tolerance, straight bright bar with higher yield strength and better chip control than hot rolled.35542018126 HB—
Quenched and tempered
Only worthwhile on sections below ~16 mm where water quenching gives a partly martensitic, higher-strength core.4206501720 HRC—
Carburized and hardened
The main reason to buy C15E: a hard 0.3–1.2 mm wear-resistant case (58–62 HRC) on a tough, still-ductile core.4507001560 HRC—

What is C15E +C?

C15E +C is C15E supplied in the +C condition — pick for close tolerance, straight bright bar with higher yield strength and better chip control than hot rolled. C15E +C has a yield strength of 355 MPa (51.5 ksi) and a tensile strength of 420 MPa (60.9 ksi) — weaker than 73% of steel grades. Elongation at break is 18% and the elastic modulus is 205 GPa (29.7 Msi). C15E +C has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,460°C (2,660 °F). +N is the default condition FabDigit quotes; +C is available on request or by drawing note.

Advantages

  • High electrical conductivity — 10.8 % IACS, better than 94% of steel grades
  • Readily welded — 92/100, better than 93% of steel grades
  • Conducts heat well — 51 W/m·K (29.5 BTU/hr·ft·°F), better than 92% of steel grades
  • Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
  • Forms and bends easily — 70/100, better than 86% of steel grades

C15E +C properties

Typical room-temperature values for C15E +C; 14 are specific to this condition. Other listed values are C15E reference data and may not represent this condition. Bars are the position among steel grades.

Physical3

C15E +C has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,460°C (2,660 °F).

Density7.85 g/cm³0.28 lb/in³
Melting Point (Solidus)1,460°C2,660 °F
Liquidus Temperature1,520°C2,768 °F

Mechanical16

C15E +C has a yield strength of 355 MPa (51.5 ksi) and a tensile strength of 420 MPa (60.9 ksi) — weaker than 73% of steel grades. Elongation at break is 18% and the elastic modulus is 205 GPa (29.7 Msi).

Elastic (Young's) Modulus205 GPa29.7 Msi
Shear Modulus80 GPa11.6 Msi
Bulk Modulus160 GPa23.2 Msi
Poisson's Ratio0.29
Tensile Strength (Ultimate)420 MPa60.9 ksi
Yield Strength (0.2% offset)355 MPa51.5 ksi
Elongation at Break18%
Reduction in Area40%
Compressive Strength325 MPa47.1 ksi
Shear Strength285 MPa41.3 ksi
Fatigue Strength (Endurance Limit)210 MPa30.5 ksi
Fracture Toughness (K_IC)110 MPa·√m100 ksi·√in
Charpy V-Notch Impact (RT)60 J44.3 ft·lbf
Hardness, Brinell126 HB
Hardness, Rockwell B71 HRB
Hardness, Vickers127 HV

Thermal6

C15E +C is rated for continuous service to 400°C (752 °F). It conducts heat at 51 W/m·K (29.5 BTU/hr·ft·°F), better than 92% of steel grades. Thermal expansion is 11.9 µm/m·K (6.61 µin/in·°F).

Thermal Conductivity51 W/m·K29.5 BTU/hr·ft·°F
Specific Heat Capacity480 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 Fusion247 J/g106 BTU/lb
Max Service Temperature (continuous)400°C752 °F
Min Service Temperature-20°C-4 °F

Electrical3

C15E +C conducts electricity at 10.8 % IACS, better than 94% of steel grades.

Electrical Conductivity10.8 % IACS
Electrical Resistivity1.6×10⁻⁷ Ω·m6.3 µΩ·in
Magnetic Responseferromagnetic

Chemical & Environmental3

Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.

Galvanic Potential (seawater, vs SCE)-0.65 V
Corrosion ResistanceNot recommended10/100
Chemical Resistance SummaryRusts freely in moist air, water and salt spray; attacked by all acids and by chlorides. Reasonably stable in dry air, oils, neutral alkalis and concrete; requires paint, zinc plating, phosphating or oiling for any outdoor service.

Sustainability4

Producing a kilogram of C15E +C takes about 25 MJ of energy and emits 1.9 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 30%.

Embodied Energy (primary production)25 MJ/kg10,748 BTU/lb
Embodied Carbon (primary production)1.9 kg CO₂/kg
Embodied Water40 L/kg4.8 gal/lb
Typical Recycled Content30%

Manufacturability6

C15E +C's machinability is fair (52/100, better than 52% of steel grades); weldability excellent (92/100); formability very good (70/100).

MachinabilityFair52/100
Machinability Rating (AISI 1212 = 100 %)66%
WeldabilityExcellent92/100
Formability (cold)Very good70/100
Brazeability / SolderabilityExcellent85/100
PolishabilityGood60/100

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with C15E +C

Is C15E easy to machine?

Soft and gummy — use sharp positive-rake tools, high speed, generous coolant and chip breakers; normalizing or cold drawing improves finish, and C15R (resulphurised) machines noticeably better.

Can C15E be welded?

Excellent weldability by MIG/TIG/MMA/spot with ER70S-type filler; CEV ≈ 0.25 so no preheat or PWHT is needed except on very thick sections, but carburized parts should not be welded.

Can C15E be formed, bent or molded?

Very good cold formability — deep drawing, bending to tight radii, cold heading and roll forming; hot forge at 1100–850 °C followed by normalizing.

What surface finishes work on C15E?

No corrosion resistance of its own: specify zinc/nickel plating, phosphate + oil, black oxide or paint; takes a fair polish but ferrite scratches easily.

C15E chemical composition (wt %)

Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.

ElementSpec limit (wt %)Nominal
C0.12 – 0.170.15
Si≤ 0.40.25
Mn0.3 – 0.60.45
P≤ 0.04—
SC15R variant is resulphurised 0.020–0.040≤ 0.04—
Crresidual≤ 0.4—
Niresidual≤ 0.4—
Moresidual; Cr+Mo+Ni ≤ 0.63≤ 0.1—
Febalance—

C15E +C — frequently asked

What is C15E +C used for?

C15E +C is typically used for shafts, bolts, case-hardened components and general machine parts. In short: excellent weldability, CEV ≈ 0.25; clean-steel case-hardening base; very high cold formability.

What is the yield strength of C15E +C?

C15E +C has a typical yield strength of 355 MPa (51.5 ksi) and a tensile strength of 420 MPa (60.9 ksi) — weaker than 73% of steel grades. Strength varies by condition: see the 8 listed tempers.

Is C15E +C easy to machine?

Reasonably — machinability is rated fair (52/100, better than 52% of steel grades). Soft and gummy — use sharp positive-rake tools, high speed, generous coolant and chip breakers; normalizing or cold drawing improves finish, and C15R (resulphurised) machines noticeably better.

Can C15E +C be welded?

Yes — weldability is rated excellent (92/100). Excellent weldability by MIG/TIG/MMA/spot with ER70S-type filler; CEV ≈ 0.25 so no preheat or PWHT is needed except on very thick sections, but carburized parts should not be welded.

What surface finishes work on C15E +C?

No corrosion resistance of its own: specify zinc/nickel plating, phosphate + oil, black oxide or paint; takes a fair polish but ferrite scratches easily.

Can C15E +C be formed, bent or molded?

Very good cold formability — deep drawing, bending to tight radii, cold heading and roll forming; hot forge at 1100–850 °C followed by normalizing.

What is the maximum service temperature of C15E +C?

C15E +C is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

What is the difference between C15E +N and C15E-CH?

+N is the default condition — standard stocked bar condition: uniform fine grain, good toughness and machining behaviour before carburizing or welding. CH: the main reason to buy C15E: a hard 0.3–1.2 mm wear-resistant case (58–62 HRC) on a tough, still-ductile core. Yield strength is 325 MPa in +N versus 450 MPa in CH.

Sources

  1. EN 10084 — Case hardening steels, technical delivery conditions — CEN (2008)
  2. EN 10083-2 — Steels for quenching and tempering: non-alloy steels — CEN (2006)
  3. JIS G 4051 — Carbon steels for machine structural use (S15C) — JSA (2016)
  4. ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys (AISI 1015) — ASM International (1990)
  5. ASM Handbook Vol.4 — Heat Treating (carburizing) — ASM International (1991)
  6. Mysteel / 1688 (2025)

Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.