Steel SUJ2 Cold Drawn
Supply condition
JIS SUJ2 · AISI/SAE 52100 · EN 100Cr6, 1.3505 · GB GCr15
Choose for close-tolerance, bright bar or wire feeding cold-heading and turning operations.
Values for the Cold Drawn condition
Other SUJ2 tempers and conditions
SUJ2 is listed in 7 conditions; see the grade overview at SUJ2.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AnnealedDefault soft, machinable delivery condition | Standard stock condition for bars, tubes and rings that will be machined and then through-hardened. | 420 | 660 | 25 | 192 HB | — |
pearlitic bar/wire | Cheapest mill condition for stock that will be spheroidize annealed before machining. | 600 | 1,000 | 10 | 31 HRC | 7.2 % IACS |
Cold DrawnThis page Cold Drawn (annealed + cold drawn bar/wire) | Choose for close-tolerance, bright bar or wire feeding cold-heading and turning operations. | 620 | 790 | 12 | 21 HRC | 7 % IACS |
Hardened + stabilized (extra temper 250–350 °C for dimensional stability) | Use for gauges, spindles and high-temperature bearings that must hold size up to ~200–250 °C, accepting 2–5 HRC lower hardness. | 1,650 | 1,900 | 3.5 | 57 HRC | 6 % IACS |
Tempered ~200–230 °C for slightly higher toughness | Pick when a little more toughness and dimensional stability is wanted at modest hardness loss (shafts, cams, gauge bodies). | 1,750 | 2,050 | 2.5 | 60 HRC | — |
Bainite hardened (isothermal/austempered ~230 °C, 58–61 HRC) | Specified for large or shock-loaded bearing rings needing compressive surface stress, better toughness and lower distortion than martensitic hardening. | 1,800 | 2,100 | 3 | 59 HRC | — |
Quenched and tempered | The functional bearing condition: maximum hardness, wear and rolling-contact fatigue resistance for races, balls and rollers. | 1,900 | 2,280 | 1.5 | 62 HRC | 36 W/m·K |
What is SUJ2 Cold Drawn?
SUJ2 Cold Drawn is SUJ2 supplied in the Cold Drawn condition — choose for close-tolerance, bright bar or wire feeding cold-heading and turning operations. SUJ2 Cold Drawn has a yield strength of 620 MPa (89.9 ksi) and a tensile strength of 790 MPa (115 ksi) — stronger than 78% of steel grades. Elongation at break is 12% and the elastic modulus is 210 GPa (30.5 Msi). SUJ2 Cold Drawn has a density of 7.81 g/cm³ (0.282 lb/in³), lighter than 84% of steel grades. It melts at 1,425°C (2,597 °F). Annealed is the default condition FabDigit quotes; Cold Drawn is available on request or by drawing note.
Advantages
- Polishes to a fine finish — 85/100, better than 99% of steel grades
- High strength — 620 MPa (89.9 ksi), better than 78% of steel grades
Limitations
- Difficult to weld — 18/100, worse than 87% of steel grades
- Limited service temperature — 250°C (482 °F), worse than 85% of steel grades
- Limited ductility — 12%, worse than 84% of steel grades
SUJ2 Cold Drawn properties
Typical room-temperature values for SUJ2 Cold Drawn; 23 are specific to this condition. Other listed values are SUJ2 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
SUJ2 Cold Drawn has a density of 7.81 g/cm³ (0.282 lb/in³), lighter than 84% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical15
SUJ2 Cold Drawn has a yield strength of 620 MPa (89.9 ksi) and a tensile strength of 790 MPa (115 ksi) — stronger than 78% of steel grades. Elongation at break is 12% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
SUJ2 Cold Drawn is rated for continuous service to 250°C (482 °F). It conducts heat at 46 W/m·K (26.6 BTU/hr·ft·°F), better than 71% of steel grades. Thermal expansion is 11.9 µm/m·K (6.61 µin/in·°F).
Electrical3
SUJ2 Cold Drawn conducts electricity at 7 % IACS, worse than 74% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of SUJ2 Cold Drawn takes about 30 MJ of energy and emits 2.3 kg of CO₂ — more than 56% of steel grades. Typical recycled content is 30%.
Manufacturability8
SUJ2 Cold Drawn's machinability is fair (48/100, worse than 57% of steel grades); weldability poor (18/100); formability poor (25/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with SUJ2 Cold Drawn
Is SUJ2 easy to machine?
Machine only in the spheroidize-annealed state (≈40 % of AISI 1212) with rigid setups and carbide tooling; hardened 60+ HRC parts require grinding, honing or CBN hard turning.
Can SUJ2 be welded?
Essentially not weldable — high carbon equivalent causes quench cracking; if unavoidable, preheat 300–400 °C and post-weld temper immediately.
Can SUJ2 be formed, bent or molded?
Cold heading and ring rolling are done from spheroidized stock; hot work 1050–850 °C followed by slow cooling and spheroidize annealing to avoid carbide network.
What surface finishes work on SUJ2?
No anodizing; protect with oil, phosphate, black oxide or thin hard chrome/nickel plating (bake to avoid hydrogen embrittlement), and superfinish raceways for low friction.
SUJ2 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 |
|---|---|---|
| CJIS G 4805 SUJ2 | 0.95 – 1.1 | 1 |
| Si | 0.15 – 0.35 | 0.25 |
| Mn | ≤ 0.5 | 0.35 |
| P | ≤ 0.03 | — |
| S | ≤ 0.03 | — |
| Cr | 1.3 – 1.6 | 1.45 |
| Ni | ≤ 0.25 | — |
| Cu | ≤ 0.25 | — |
| Mo | ≤ 0.08 | — |
| Otypical clean-steel oxygen limit for bearing quality | ≤ 0 | — |
| Fe | balance | — |
SUJ2 Cold Drawn — frequently asked
What is SUJ2 Cold Drawn used for?
SUJ2 Cold Drawn is typically used for ball bearing rings and balls, roller bearings and rollers, precision shafts and spindles, linear guide rails, cam followers and gauges and measuring blocks. In short: premium bearing tool steel.
What is the yield strength of SUJ2 Cold Drawn?
SUJ2 Cold Drawn has a typical yield strength of 620 MPa (89.9 ksi) and a tensile strength of 790 MPa (115 ksi) — stronger than 78% of steel grades. Strength varies by condition: see the 7 listed tempers.
Is SUJ2 Cold Drawn easy to machine?
Reasonably — machinability is rated fair (48/100, worse than 57% of steel grades). Machine only in the spheroidize-annealed state (≈40 % of AISI 1212) with rigid setups and carbide tooling; hardened 60+ HRC parts require grinding, honing or CBN hard turning.
Can SUJ2 Cold Drawn be welded?
Not readily — weldability is rated poor (18/100). Essentially not weldable — high carbon equivalent causes quench cracking; if unavoidable, preheat 300–400 °C and post-weld temper immediately.
What surface finishes work on SUJ2 Cold Drawn?
No anodizing; protect with oil, phosphate, black oxide or thin hard chrome/nickel plating (bake to avoid hydrogen embrittlement), and superfinish raceways for low friction.
Can SUJ2 Cold Drawn be formed, bent or molded?
Cold heading and ring rolling are done from spheroidized stock; hot work 1050–850 °C followed by slow cooling and spheroidize annealing to avoid carbide network.
What is the maximum service temperature of SUJ2 Cold Drawn?
SUJ2 Cold Drawn is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in SUJ2 Cold Drawn?
Yes — SUJ2 Cold Drawn 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
- JIS G 4805 High carbon chromium bearing steels — JISC (2019)
- GB/T 18254 High-carbon chromium bearing steel — SAC (2016)
- ASTM A295 Standard Specification for High-Carbon Anti-Friction Bearing Steel — ASTM (2020)
- EN ISO 683-17 (100Cr6) Heat-treatable steels — ball and roller bearing steels — ISO (2014)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.16 — Machining — ASM International (1989)
- 100Cr6 / SUJ2 bearing steel datasheet — Ovako / Böhler (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.