Steel 20Cr3-CH (Carburized and hardened)
Heat-treated state
EN 20Cr3
The functional condition for bearing rings, rollers and needles: hard 60–64 HRC case over a tough 30–42 HRC core.
Values for the CH condition
Other 20Cr3 tempers and conditions
20Cr3 is listed in 7 conditions; see the grade overview at 20Cr3.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Spheroidize annealed | Pick for cold heading, cold extrusion or deep-drawn ring blanks that need maximum cold formability. | 290 | 500 | 26 | 155 HB | — |
Treated for shearability | For wire and bar that is cold sheared into slugs before cold heading of bearing rollers. | 310 | 520 | 24 | 165 HB | 8 % IACS |
+ADefault Annealed | Standard stock condition for bar and tube that will be machined and then carburized. | 320 | 550 | 22 | 170 HB | — |
Treated to hardness range | Choose when automatic-lathe turning needs a narrow, repeatable hardness band and good chip breaking. | 400 | 620 | 18 | 180 HB | — |
Cold drawn | Bright, close-tolerance bar for automatic screw machining of small rollers and pins before carburizing. | 550 | 680 | 11 | 210 HB | — |
Hardenability-guaranteed (Jominy band), shown after direct hardening +… | Order +H when the Jominy hardenability band must be guaranteed for a defined case/core depth; properties listed are for the directly hardened and low-tempered condition. | 750 | 1,000 | 11 | 34 HRC | — |
CHThis page Carburized and hardened | The functional condition for bearing rings, rollers and needles: hard 60–64 HRC case over a tough 30–42 HRC core. | 850 | 1,150 | 9 | 62 HRC | — |
What is 20Cr3-CH?
20Cr3-CH is 20Cr3 heat treated to CH — the functional condition for bearing rings, rollers and needles: hard 60–64 HRC case over a tough 30–42 HRC core. 20Cr3-CH has a yield strength of 850 MPa (123 ksi) and a tensile strength of 1,150 MPa (167 ksi) — stronger than 88% of steel grades. Elongation at break is 9% and the elastic modulus is 210 GPa (30.5 Msi). 20Cr3-CH has a density of 7.83 g/cm³ (0.283 lb/in³), lighter than 80% of steel grades. It melts at 1,420°C (2,588 °F). +A is the default condition FabDigit quotes; CH is available on request or by drawing note.
Advantages
- Polishes to a fine finish — 85/100, better than 99% of steel grades
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
- High strength — 850 MPa (123 ksi), better than 88% of steel grades
Limitations
- Limited service temperature — 150°C (302 °F), worse than 99% of steel grades
- Difficult to machine — 10/100, worse than 99% of steel grades
- Difficult to weld — 10/100, worse than 99% of steel grades
- Limited formability — 5/100, worse than 99% of steel grades
- Low fracture toughness — 30 MPa·√m (27.3 ksi·√in), worse than 96% of steel grades
20Cr3-CH properties
Typical room-temperature values for 20Cr3-CH; 16 are specific to this condition. Other listed values are 20Cr3 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
20Cr3-CH has a density of 7.83 g/cm³ (0.283 lb/in³), lighter than 80% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical15
20Cr3-CH has a yield strength of 850 MPa (123 ksi) and a tensile strength of 1,150 MPa (167 ksi) — stronger than 88% of steel grades. Elongation at break is 9% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
20Cr3-CH is rated for continuous service to 150°C (302 °F). It conducts heat at 44 W/m·K (25.4 BTU/hr·ft·°F), better than 57% of steel grades. Thermal expansion is 11.9 µm/m·K (6.61 µin/in·°F).
Electrical3
20Cr3-CH conducts electricity at 8 % IACS, better than 55% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of 20Cr3-CH takes about 24 MJ of energy and emits 1.9 kg of CO₂ — less than 97% of steel grades. Typical recycled content is 30%.
Manufacturability7
20Cr3-CH's machinability is not recommended (10/100, worse than 99% of steel grades); weldability not recommended (10/100); formability not recommended (5/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 20Cr3-CH
Is 20Cr3 easy to machine?
Machine in +A/+AC/+TH before carburizing with coated carbide at moderate speed; after case hardening only grinding, honing or CBN turning is practical.
Can 20Cr3 be welded?
Weldable only in the uncarburized state with 200–300 °C preheat and post-weld stress relief; never weld carburized surfaces.
Can 20Cr3 be formed, bent or molded?
Spheroidize-annealed (+AC) stock cold heads and cold extrudes well; hot forge at 1050–1150 °C and normalize at ~880 °C before carburizing.
What surface finishes work on 20Cr3?
Case-hardened parts are ground and honed to bearing finish; corrosion protection by oiling, manganese phosphating, black oxide or thin Zn/Ni plating (no anodizing).
20Cr3 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 |
|---|---|---|
| Cper EN ISO 683-17 case-hardening bearing steels | 0.17 – 0.23 | 0.2 |
| Si | 0.15 – 0.4 | 0.25 |
| Mn | 0.3 – 0.6 | 0.45 |
| CrCr/4 ≈ 3 gives the '3' in 20Cr3 | 0.6 – 0.9 | 0.75 |
| P | ≤ 0.03 | — |
| S | ≤ 0.03 | — |
| Moresidual max | ≤ 0.1 | — |
| Niresidual max | ≤ 0.3 | — |
| Curesidual max | ≤ 0.3 | — |
| O≤15 ppm total oxygen for bearing quality | ≤ 0 | — |
| Fe | balance | — |
20Cr3-CH — frequently asked
What is 20Cr3-CH used for?
20Cr3-CH is typically used for case-hardened bearing races, rollers and pins for rolling bearings and heavy-duty industrial bearing components. In short: bearing-grade case-hardening steel; hard case, tough core; good cold-heading in +AC.
What is the yield strength of 20Cr3-CH?
20Cr3-CH has a typical yield strength of 850 MPa (123 ksi) and a tensile strength of 1,150 MPa (167 ksi) — stronger than 88% of steel grades. Strength varies by condition: see the 7 listed tempers.
Is 20Cr3-CH easy to machine?
Not especially — machinability is rated not recommended (10/100, worse than 99% of steel grades). Machine in +A/+AC/+TH before carburizing with coated carbide at moderate speed; after case hardening only grinding, honing or CBN turning is practical.
Can 20Cr3-CH be welded?
Not readily — weldability is rated not recommended (10/100). Weldable only in the uncarburized state with 200–300 °C preheat and post-weld stress relief; never weld carburized surfaces.
What surface finishes work on 20Cr3-CH?
Case-hardened parts are ground and honed to bearing finish; corrosion protection by oiling, manganese phosphating, black oxide or thin Zn/Ni plating (no anodizing).
Can 20Cr3-CH be formed, bent or molded?
Spheroidize-annealed (+AC) stock cold heads and cold extrudes well; hot forge at 1050–1150 °C and normalize at ~880 °C before carburizing.
What is the maximum service temperature of 20Cr3-CH?
20Cr3-CH is rated for continuous use to about 150°C (302 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 20Cr3 +A and 20Cr3-CH?
+A is the default condition — standard stock condition for bar and tube that will be machined and then carburized. CH: the functional condition for bearing rings, rollers and needles: hard 60–64 HRC case over a tough 30–42 HRC core. Yield strength is 320 MPa in +A versus 850 MPa in CH.
Sources
- EN ISO 683-17 Heat-treatable steels – Ball and roller bearing steels — ISO/CEN (2014)
- EN 10084 Case hardening steels – Technical delivery conditions — CEN (2008)
- DIN 17230 Wälzlagerstähle — DIN (1980)
- ASM Handbook Vol.1 – Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- Machinery's Handbook (machinability ratings) — Industrial Press (2020)
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.