Steel 100Cr6
EN 100Cr6 · AISI/SAE 52100 · JIS SUJ2 · GB GCr15 · ISO 683-17
100Cr6 (52100, GCr15, SUJ2, 1.3505) is the standard through-hardening high-carbon chromium bearing steel, with about 1 % C and 1.5 % Cr that quench and temper to a fine martensite plus uniformly distributed carbide structure at 60–64 HRC for maximum hardness, rolling-contact fatigue life and dimensional stability.
Values for the Annealed condition
100Cr6 tempers and conditions
100Cr6 is supplied in 9 conditions, soft to hard. Annealed is the default FabDigit quotes; the values on this page are for it.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Spheroidize annealed | Standard EN ISO 683-17 delivery condition: globular carbides in ferrite, max ~207 HB, optimised for machining and cold forming before hardening. | 410 | 640 | 22 | 190 HB | 44 W/m·K |
AnnealedDefault ~180–210 HB | Standard stock condition: uniform spheroidized carbides for best machinability, cold forming and subsequent hardening response. | 420 | 660 | 22 | 200 HB | 45 W/m·K |
Hot rolled | Cheapest bar form for parts that will be fully re-annealed and hardened; hard, poorly machinable lamellar/pearlitic structure as delivered. | 550 | 950 | 10 | 29 HRC | 8 % IACS |
Normalized | Intermediate treatment to homogenise structure and break up carbide networks before spheroidize annealing or hardening. | 570 | 1,000 | 9 | 31 HRC | 8 % IACS |
Spheroidize Annealed + Cold Drawn | Spheroidized bar given a light cold-drawing pass for close tolerance and bright finish; strength and hardness rise, ductility and formability drop versus +AC. | 600 | 760 | 11 | 225 HB | 44 W/m·K |
Cold drawn | Use for close-tolerance bright bar, ball/roller wire and cold-headed blanks; slightly higher strength and lower ductility than annealed. | 620 | 800 | 12 | 21 HRC | 8 % IACS |
Hardened and tempered ~250 °C, 55–58 HRC | Choose when parts must run warm (to ~200 °C) or need extra toughness and dimensional stability at some loss of hardness. | 1,700 | 1,900 | 3 | 57 HRC | — |
Isothermally bainite hardened (austempered), 58–62 HRC | Pick for higher toughness, compressive surface stresses and better resistance to contamination/impact loading in bearings and rings. | 1,800 | 2,100 | 2 | 60 HRC | — |
Quenched and tempered | Standard bearing/tool condition: maximum hardness, wear and rolling-contact fatigue life; use below ~120–150 °C to keep dimensional stability. | 1,900 | 2,240 | 1 | 62 HRC | 34 W/m·K |
What is 100Cr6?
100Cr6 (52100, GCr15, SUJ2, 1.3505) is the standard through-hardening high-carbon chromium bearing steel, with about 1 % C and 1.5 % Cr that quench and temper to a fine martensite plus uniformly distributed carbide structure at 60–64 HRC for maximum hardness, rolling-contact fatigue life and dimensional stability. It is normally supplied spheroidize-annealed (420 MPa yield, 660 MPa tensile, 22 % elongation, 200 HB) so bars, rings and tubes can be machined or cold formed before hardening. Limits are restricted hardenability (full through-hardening generally below about 30 mm diameter), no corrosion resistance, low toughness, very poor weldability, and a service ceiling of roughly 120–150 °C in the standard temper. 100Cr6 has a density of 7.81 g/cm³ (0.282 lb/in³), lighter than 84% of steel grades. It melts at 1,424°C (2,595 °F). 100Cr6 has a yield strength of 420 MPa (60.9 ksi) and a tensile strength of 660 MPa (95.7 ksi) — weaker than 53% of steel grades. Elongation at break is 22% and the elastic modulus is 210 GPa (30.5 Msi).
What is 100Cr6 used for?
- Ball bearing rings and balls
- Cylindrical and taper roller bearing races
- Ball screw shafts and nuts
- Linear guide rails and blocks
- Cam followers and track rollers
- Precision gauges and gauge blocks
- Cold-forming punches and dies
Advantages
- Polishes to a fine finish — 88/100, better than 100% of steel grades
Limitations
- Difficult to weld — 12/100, worse than 96% of steel grades
- Limited service temperature — 200°C (392 °F), worse than 93% of steel grades
100Cr6 properties
Typical room-temperature values for 100Cr6-Annealed; bars are the position among steel grades.
Physical3
100Cr6 has a density of 7.81 g/cm³ (0.282 lb/in³), lighter than 84% of steel grades. It melts at 1,424°C (2,595 °F).
Mechanical14
100Cr6 has a yield strength of 420 MPa (60.9 ksi) and a tensile strength of 660 MPa (95.7 ksi) — weaker than 53% of steel grades. Elongation at break is 22% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
100Cr6 is rated for continuous service to 200°C (392 °F). It conducts heat at 45 W/m·K (26 BTU/hr·ft·°F), better than 66% of steel grades. Thermal expansion is 11.9 µm/m·K (6.61 µin/in·°F).
Electrical3
100Cr6 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 100Cr6 takes about 32 MJ of energy and emits 2.3 kg of CO₂ — more than 70% of steel grades. Typical recycled content is 30%.
Manufacturability7
100Cr6's machinability is fair (45/100, worse than 65% of steel grades); weldability not recommended (12/100); formability fair (35/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. 100Cr6 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 100Cr6
Is 100Cr6 easy to machine?
Machine only in the spheroidize annealed state (~200 HB) with rigid setups and carbide tooling; hardened 60+ HRC parts require grinding, honing or CBN hard turning.
Can 100Cr6 be welded?
Essentially unweldable in production — 1%C gives severe cracking; if unavoidable, preheat 300–400 °C, use low-hydrogen/austenitic filler and post-weld anneal immediately.
Can 100Cr6 be formed, bent or molded?
Cold heading, drawing and ring rolling are done soft annealed; hot work 850–1050 °C then slow cool and re-spheroidize, and always harden from 830–860 °C with oil/salt quench plus prompt tempering.
Manufacturability
The process limits FabDigit applies to 100Cr6. Every 100Cr6 part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
CNC machining
| Machinability | Fair45 / 100 |
|---|---|
| ISO material group | P.1 |
| Cutting speed (rough / finish) | 220 / 260 m/min |
| Minimum wall | 0.8 mm |
| Minimum internal radius | 1 mm |
| Drill depth limit | 5× diameter |
| Best surface (machined / polished) | Ra 1.6 / — |
| Hardenable after machining | No |
Sheet metal
| Formability | Not Recommend35 / 100 |
|---|---|
| Weldability | Poor12 / 100 |
100Cr6 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 |
|---|---|---|
| CGB/T 18254 GCr15: 0.95–1.05 | 0.93 – 1.05 | 1 |
| Si | 0.15 – 0.35 | 0.25 |
| Mn | 0.25 – 0.45 | 0.35 |
| Cr | 1.35 – 1.6 | 1.45 |
| P | ≤ 0.03 | |
| S | ≤ 0.02 | |
| Niresidual, max | ≤ 0.3 | |
| Curesidual, max | ≤ 0.3 | |
| Moresidual, max | ≤ 0.1 | |
| O≤15 ppm for high-cleanliness bearing quality | ≤ 0 | |
| Fe | balance |
What surface finishes work on 100Cr6?
No inherent corrosion protection: finish with oil, phosphate, black oxide, zinc or hard chrome; the fine carbide structure takes a mirror polish and is ideal for superfinished raceways.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Plating
CVD Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel 100Cr6 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
How much does 100Cr6 cost?
100Cr6 is a standard-cost steel ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
100Cr6 — frequently asked
What is 100Cr6 used for?
100Cr6 is typically used for ball bearing rings and balls, cylindrical and taper roller bearing races, ball screw shafts and nuts, linear guide rails and blocks, cam followers and track rollers and precision gauges and gauge blocks. In short: workhorse bearing steel.
What is the yield strength of 100Cr6?
100Cr6 has a typical yield strength of 420 MPa (60.9 ksi) and a tensile strength of 660 MPa (95.7 ksi) — weaker than 53% of steel grades. Strength varies by condition: see the 9 listed tempers.
Is 100Cr6 easy to machine?
Reasonably — machinability is rated fair (45/100, worse than 65% of steel grades). Machine only in the spheroidize annealed state (~200 HB) with rigid setups and carbide tooling; hardened 60+ HRC parts require grinding, honing or CBN hard turning.
Can 100Cr6 be welded?
Not readily — weldability is rated not recommended (12/100). Essentially unweldable in production — 1%C gives severe cracking; if unavoidable, preheat 300–400 °C, use low-hydrogen/austenitic filler and post-weld anneal immediately.
What surface finishes work on 100Cr6?
No inherent corrosion protection: finish with oil, phosphate, black oxide, zinc or hard chrome; the fine carbide structure takes a mirror polish and is ideal for superfinished raceways.
Can 100Cr6 be formed, bent or molded?
Cold heading, drawing and ring rolling are done soft annealed; hot work 850–1050 °C then slow cool and re-spheroidize, and always harden from 830–860 °C with oil/salt quench plus prompt tempering.
What is the maximum service temperature of 100Cr6?
100Cr6 is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 100Cr6 Annealed and 100Cr6-BH?
Annealed is the default condition — standard stock condition: uniform spheroidized carbides for best machinability, cold forming and subsequent hardening response. BH: pick for higher toughness, compressive surface stresses and better resistance to contamination/impact loading in bearings and rings. Yield strength is 420 MPa in Annealed versus 1,800 MPa in BH.
How much does 100Cr6 cost?
100Cr6 is a standard-cost steel ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Can FabDigit make parts in 100Cr6?
Yes — 100Cr6 is available for CNC machining and sheet metal; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- EN ISO 683-17 Heat-treatable steels — Ball and roller bearing steels — ISO/CEN (2014)
- GB/T 18254 (GCr15) — SAC (2016)
- ASTM A295 High-Carbon Anti-Friction Bearing Steel (52100) — ASTM (2014)
- JIS G 4805 High carbon chromium bearing steels (SUJ2) — JSA (2019)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- Bearing steel 100Cr6 / 52100 bar datasheets — Ovako / Sandvik / Böhler (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.