Steel C15C +U+C (Untreated then cold drawn)
Supply condition
EN 1.0234
Drawn straight from hot-rolled rod: highest as-drawn strength, lowest ductility — for light upsetting, pins and shafts.
Values for the +U+C condition
Other C15C tempers and conditions
C15C is listed in 8 conditions; see the grade overview at C15C.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Spheroidize annealed | Softest, most formable condition — choose for severe multi-station cold heading or deep cold extrusion. | 230 | 390 | 33 | 110 HB | — |
Annealed | General soft-annealed rod/bar for moderate forming or machining when full spheroidization is not required. | 240 | 400 | 31 | 115 HB | 10.8 % IACS |
Hot rolled | Base hot-rolled coil/rod supplied for further drawing or light upsetting; lowest cost condition. | 260 | 420 | 28 | 120 HB | — |
Normalized | Normalized bar/forging condition giving a uniform fine ferrite-pearlite structure before machining or case hardening. | 275 | 430 | 27 | 126 HB | 10.5 % IACS |
Light cold drawn | Small drawing reduction for size and surface only — keeps near-annealed ductility for heavy heading. | 300 | 420 | 22 | 125 HB | 10.5 % IACS |
+AC+CDefault Spheroidize annealed then cold drawn to size | Standard cold-heading wire condition: drawn to tolerance and surface finish while keeping spheroidized, headable structure. | 360 | 450 | 14 | 135 HB | — |
+U+CThis page Untreated then cold drawn | Drawn straight from hot-rolled rod: highest as-drawn strength, lowest ductility — for light upsetting, pins and shafts. | 460 | 540 | 10 | 160 HB | — |
carburized/carbonitrided, quenched and low-temperature tempered | For headed parts needing a hard wear surface (self-tapping screws, pins) over a tough, low-strength core. | 480 | 700 | 12 | 60 HRC | — |
What is C15C +U+C?
C15C +U+C is C15C supplied in the +U+C condition — drawn straight from hot-rolled rod: highest as-drawn strength, lowest ductility — for light upsetting, pins and shafts. C15C +U+C has a yield strength of 460 MPa (66.7 ksi) and a tensile strength of 540 MPa (78.3 ksi) — stronger than 55% of steel grades. Elongation at break is 10% and the elastic modulus is 207 GPa (30 Msi). C15C +U+C has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,465°C (2,669 °F). +AC+C is the default condition FabDigit quotes; +U+C is available on request or by drawing note.
Advantages
- 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
- High electrical conductivity — 10.5 % IACS, better than 89% of steel grades
- Easy to machine — 62/100, better than 89% of steel grades
Limitations
- Limited ductility — 10%, worse than 91% of steel grades
- Limited service temperature — 300°C (572 °F), worse than 78% of steel grades
C15C +U+C properties
Typical room-temperature values for C15C +U+C; 14 are specific to this condition. Other listed values are C15C reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
C15C +U+C has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,465°C (2,669 °F).
Mechanical16
C15C +U+C has a yield strength of 460 MPa (66.7 ksi) and a tensile strength of 540 MPa (78.3 ksi) — stronger than 55% of steel grades. Elongation at break is 10% and the elastic modulus is 207 GPa (30 Msi).
Thermal6
C15C +U+C is rated for continuous service to 300°C (572 °F). It conducts heat at 51 W/m·K (29.5 BTU/hr·ft·°F), better than 92% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
C15C +U+C conducts electricity at 10.5 % IACS, better than 89% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.
Sustainability4
Producing a kilogram of C15C +U+C takes about 25 MJ of energy and emits 1.9 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 25%.
Manufacturability7
C15C +U+C's machinability is good (62/100, better than 89% of steel grades); weldability excellent (92/100); formability good (62/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C15C +U+C
Is C15C easy to machine?
Soft and gummy — use sharp positive-rake tools, high speed and generous coolant to avoid built-up edge; cold-drawn or normalized condition machines better than fully spheroidized.
Can C15C be welded?
Excellent weldability (CEV ≈ 0.25); MIG/TIG/resistance/projection welding with no preheat in normal sections, ER70S-type filler.
Can C15C be formed, bent or molded?
Designed for multi-station cold heading and cold extrusion in +AC or +AC+C condition with phosphate + soap or polymer lubricant; interstage anneal only for very severe upset ratios.
What surface finishes work on C15C?
No corrosion resistance of its own — zinc/zinc-nickel electroplate (with baking to avoid hydrogen embrittlement), zinc-flake coating, black oxide or phosphate + oil; takes plating and paint readily.
C15C 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.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| CEN 10263-2 cast analysis | 0.12 – 0.18 | 0.15 |
| Silow-Si versions (≤0.10) available for wire drawing/plating | ≤ 0.3 | 0.15 |
| Mn | 0.3 – 0.6 | 0.45 |
| P | ≤ 0.03 | 0.02 |
| S | ≤ 0.03 | 0.02 |
| Curesidual limit | ≤ 0.25 | 0.1 |
| Fe | balance | — |
C15C +U+C — frequently asked
What is C15C +U+C used for?
C15C +U+C is typically used for cold-formed fasteners, screws and pins, cold-extruded machine parts and wire products. In short: stronger cold-heading grade; case-hardenable fastener steel; formability score 88.
What is the yield strength of C15C +U+C?
C15C +U+C has a typical yield strength of 460 MPa (66.7 ksi) and a tensile strength of 540 MPa (78.3 ksi) — stronger than 55% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is C15C +U+C easy to machine?
Reasonably — machinability is rated good (62/100, better than 89% of steel grades). Soft and gummy — use sharp positive-rake tools, high speed and generous coolant to avoid built-up edge; cold-drawn or normalized condition machines better than fully spheroidized.
Can C15C +U+C be welded?
Yes — weldability is rated excellent (92/100). Excellent weldability (CEV ≈ 0.25); MIG/TIG/resistance/projection welding with no preheat in normal sections, ER70S-type filler.
What surface finishes work on C15C +U+C?
No corrosion resistance of its own — zinc/zinc-nickel electroplate (with baking to avoid hydrogen embrittlement), zinc-flake coating, black oxide or phosphate + oil; takes plating and paint readily.
Can C15C +U+C be formed, bent or molded?
Designed for multi-station cold heading and cold extrusion in +AC or +AC+C condition with phosphate + soap or polymer lubricant; interstage anneal only for very severe upset ratios.
What is the maximum service temperature of C15C +U+C?
C15C +U+C is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- EN 10263-2: Steel rod, bars and wire for cold heading and cold extrusion — non heat-treatable steels — CEN (2017)
- EN 10263-4 (case hardening steels for cold heading) — CEN (2017)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.16 — Machining — ASM International (1989)
- Cold heading wire grade datasheets (C10C/C15C) — European and Chinese wire rod producers (2023)
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.