Steel 15Cr3-CH (Carburized and hardened)
Heat-treated state
EN 15Cr3
Final service condition: hard wear-resistant case with tough core, for small carburized gears/pins.
Values for the CH condition
Other 15Cr3 tempers and conditions
15Cr3 is listed in 7 conditions; see the grade overview at 15Cr3.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Treated for shearability | Softest delivery condition, for cold-shearing blanks for cold heading/forging. | 285 | 490 | 25 | 145 HB | 8.5 % IACS |
+ADefault Annealed | Standard stock condition for machining and cold forming before carburizing. | 300 | 520 | 22 | 155 HB | 8.5 % IACS |
Treated to ferrite-pearlite structure with specified hardness range | Choose when consistent, chip-friendly microstructure is needed for automatic machining. | 330 | 540 | 20 | 155 HB | 8.5 % IACS |
Normalized | Uniform fine ferrite-pearlite structure after forging; good baseline before carburizing. | 350 | 570 | 20 | 170 HB | 8.5 % IACS |
Treated to a specified hardness range | Ordered when a narrow as-delivered hardness band is required for CNC turning lines. | 350 | 560 | 19 | 165 HB | 8.5 % IACS |
CHThis page Carburized and hardened | Final service condition: hard wear-resistant case with tough core, for small carburized gears/pins. | 440 | 760 | 11 | 60 HRC | — |
Cold drawn | Bright, close-tolerance bar for parts machined with minimal stock removal. | 520 | 660 | 9 | 195 HB | 8.5 % IACS |
What is 15Cr3-CH?
15Cr3-CH is 15Cr3 heat treated to CH — final service condition: hard wear-resistant case with tough core, for small carburized gears/pins. 15Cr3-CH has a yield strength of 440 MPa (63.8 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 50% of steel grades. Elongation at break is 11% and the elastic modulus is 210 GPa (30.5 Msi). 15Cr3-CH has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F). +A is the default condition FabDigit quotes; CH is available on request or by drawing note.
Advantages
- Polishes to a fine finish — 75/100, better than 94% of steel grades
- Forms and bends easily — 75/100, better than 90% of steel grades
- Easy to machine — 62/100, better than 89% of steel grades
Limitations
- Limited service temperature — 180°C (356 °F), worse than 98% of steel grades
- Difficult to weld — 15/100, worse than 91% of steel grades
- Limited ductility — 11%, worse than 89% of steel grades
15Cr3-CH properties
Typical room-temperature values for 15Cr3-CH; 14 are specific to this condition. Other listed values are 15Cr3 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
15Cr3-CH has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical16
15Cr3-CH has a yield strength of 440 MPa (63.8 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 50% of steel grades. Elongation at break is 11% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
15Cr3-CH is rated for continuous service to 180°C (356 °F). It conducts heat at 44 W/m·K (25.4 BTU/hr·ft·°F), better than 57% of steel grades. Thermal expansion is 11.6 µm/m·K (6.44 µin/in·°F).
Electrical3
15Cr3-CH conducts electricity at 8.5 % IACS, better than 63% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of 15Cr3-CH takes about 29 MJ of energy and emits 2.1 kg of CO₂ — less than 53% of steel grades. Typical recycled content is 25%.
Manufacturability7
15Cr3-CH's machinability is good (62/100, better than 89% of steel grades); weldability poor (15/100); formability very good (75/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 15Cr3-CH
Is 15Cr3 easy to machine?
Machine in +A/+FP condition; low-carbon gumminess favours sharp positive-rake carbide, high speed and good coolant — machinability ≈65% of 1212.
Can 15Cr3 be welded?
Weld only before carburizing (CE ≈0.4): MAG/TIG with low-hydrogen practice, preheat 100–150 °C on thick sections; carburized cases are effectively unweldable.
Can 15Cr3 be formed, bent or molded?
Good cold heading, upsetting and bending in +A/+S; hot forge 1100–850 °C then normalize at 880–920 °C.
What surface finishes work on 15Cr3?
Carburize 900–930 °C, oil quench, temper 150–200 °C; parts are then ground, and rust-protected by oiling, phosphating, black oxide or Zn/Ni plating (no anodizing).
15Cr3 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 |
|---|---|---|
| C | 0.12 – 0.18 | 0.15 |
| Si | ≤ 0.4 | 0.25 |
| Mn | 0.4 – 0.6 | 0.5 |
| P | ≤ 0.03 | 0.02 |
| S0.020–0.040 for +S free-machining variants | ≤ 0.04 | 0.02 |
| Cr | 0.5 – 0.8 | 0.65 |
| Fe | balance | — |
15Cr3-CH — frequently asked
What is 15Cr3-CH used for?
15Cr3-CH is typically used for light-duty gears, pins and dowels, bushings and sleeves, small shafts and spindles, cold-headed studs and fasteners and levers and latch components. In short: lowest-cost Cr carburizing steel; best cold formability in family; light-duty case-hardened parts.
What is the yield strength of 15Cr3-CH?
15Cr3-CH has a typical yield strength of 440 MPa (63.8 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 50% of steel grades. Strength varies by condition: see the 7 listed tempers.
Is 15Cr3-CH easy to machine?
Reasonably — machinability is rated good (62/100, better than 89% of steel grades). Machine in +A/+FP condition; low-carbon gumminess favours sharp positive-rake carbide, high speed and good coolant — machinability ≈65% of 1212.
Can 15Cr3-CH be welded?
Not readily — weldability is rated poor (15/100). Weld only before carburizing (CE ≈0.4): MAG/TIG with low-hydrogen practice, preheat 100–150 °C on thick sections; carburized cases are effectively unweldable.
What surface finishes work on 15Cr3-CH?
Carburize 900–930 °C, oil quench, temper 150–200 °C; parts are then ground, and rust-protected by oiling, phosphating, black oxide or Zn/Ni plating (no anodizing).
Can 15Cr3-CH be formed, bent or molded?
Good cold heading, upsetting and bending in +A/+S; hot forge 1100–850 °C then normalize at 880–920 °C.
What is the maximum service temperature of 15Cr3-CH?
15Cr3-CH is rated for continuous use to about 180°C (356 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 15Cr3 +A and 15Cr3-CH?
+A is the default condition — standard stock condition for machining and cold forming before carburizing. CH: final service condition: hard wear-resistant case with tough core, for small carburized gears/pins. Yield strength is 300 MPa in +A versus 440 MPa in CH.
Sources
- EN 10084 — Case hardening steels: technical delivery conditions — CEN (2008)
- EN 10027-2 material number 1.7015 — CEN (2015)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- ASM Handbook Vol.4 — Heat Treating (carburizing) — ASM International (1991)
- Case-hardening steel datasheets (1.7015 / 15Cr3) — European long-product mills / stockists (2022)
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.