Steel 11SMnPb30 · supply condition
Steel 11SMnPb30-CR
Properties of the CR condition, compared with the other 11SMnPb30 tempers.
Use for cold-rolled flats, squares and hexagons where a smooth as-rolled surface and tight thickness are wanted.
What is 11SMnPb30-CR?
11SMnPb30-CR is 11SMnPb30 supplied in the CR condition — use for cold-rolled flats, squares and hexagons where a smooth as-rolled surface and tight thickness are wanted. 11SMnPb30-CR has a yield strength of 410 MPa (59.5 ksi) and a tensile strength of 540 MPa (78.3 ksi) — weaker than 57% of steel grades. Elongation at break is 9% and the elastic modulus is 210 GPa (30.5 Msi). 11SMnPb30-CR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F). HR is the default condition FabDigit quotes; CR is available on request or by drawing note.
Advantages
- Easy to machine — 95/100, better than 100% of steel grades
- Conducts heat well — 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades
Limitations
- Difficult to weld — 12/100, worse than 96% of steel grades
- Limited ductility — 9%, worse than 93% of steel grades
- Limited service temperature — 250°C (482 °F), worse than 85% of steel grades
11SMnPb30-CR properties
Typical room-temperature values for 11SMnPb30-CR — 8 properties are specific to this condition; the rest are grade-level values shared by every 11SMnPb30 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
11SMnPb30-CR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical14
11SMnPb30-CR has a yield strength of 410 MPa (59.5 ksi) and a tensile strength of 540 MPa (78.3 ksi) — weaker than 57% of steel grades. Elongation at break is 9% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
11SMnPb30-CR is rated for continuous service to 250°C (482 °F). It conducts heat at 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades. Thermal expansion is 11.5 µm/m·K (6.39 µin/in·°F).
Electrical3
11SMnPb30-CR conducts electricity at 9.5 % IACS, better than 74% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 87% of steel grades.
Sustainability4
Producing a kilogram of 11SMnPb30-CR takes about 25 MJ of energy and emits 2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 35%.
Manufacturability7
11SMnPb30-CR's machinability is excellent (95/100, better than 100% of steel grades); weldability not recommended (12/100); formability poor (28/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 11SMnPb30 tempers and conditions
11SMnPb30 is also supplied in 5 other conditions. The full side-by-side table is on the 11SMnPb30 overview.
- HRDefaultCheapest bar form for large diameters or when parts are fully machined from oversize stock.260 MPa yield · 135 HB
- SHPick when higher yield strength / straightness is needed for slender turned or ground shafts.550 MPa yield · 200 HB
- CDDefault stock condition: close tolerance h9/h11 bright bar for automatic-lathe / CNC turning of small parts.420 MPa yield · 170 HB
- CRUse for cold-rolled flats, squares and hexagons where a smooth as-rolled surface and tight thickness are wanted.410 MPa yield · 165 HB
- AnnealedUse when maximum ductility for cold heading, staking or riveting is required, accepting lower strength.240 MPa yield · 120 HB
Working with 11SMnPb30-CR
Is 11SMnPb30 easy to machine?
Outstanding: high speeds with HSS or carbide, short broken chips, excellent surface and long tool life — the benchmark free-cutting steel for automatic lathes.
Can 11SMnPb30 be welded?
Not recommended — high sulphur and lead cause hot cracking and porosity; if unavoidable, use low-hydrogen filler, preheat and fume extraction for Pb.
Can 11SMnPb30 be formed, bent or molded?
Poor cold formability and bendability due to MnS/Pb inclusions; only light cold heading or staking in the annealed condition, hot forming above ~1150 °C with care.
What surface finishes work on 11SMnPb30?
No anodizing; protect by zinc or Zn-Ni electroplating, phosphating, black oxide or oiling. Case-carbonitriding or salt-bath nitrocarburising can be applied for wear surfaces.
11SMnPb30 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 10087 max | ≤ 0.14 | 0.1 |
| Silow Si to keep chips brittle | ≤ 0.05 | 0.03 |
| Mn | 0.9 – 1.3 | 1.1 |
| P | ≤ 0.11 | 0.06 |
| SMnS inclusions for chip breaking | 0.27 – 0.33 | 0.3 |
| Pbfree-machining additive | 0.2 – 0.35 | 0.27 |
| Fe | balance | — |
11SMnPb30-CR — frequently asked
What is 11SMnPb30-CR used for?
11SMnPb30-CR is typically used for screw machine parts, hydraulic and pneumatic fittings, threaded inserts and nuts, bushings and spacers, connector shells and low-pressure valve stems. In short: leaded free-machining bar.
What is the yield strength of 11SMnPb30-CR?
11SMnPb30-CR has a typical yield strength of 410 MPa (59.5 ksi) and a tensile strength of 540 MPa (78.3 ksi) — weaker than 57% of steel grades. Strength varies by condition: see the 6 listed tempers.
Is 11SMnPb30-CR easy to machine?
Yes — machinability is rated excellent (95/100, better than 100% of steel grades). Outstanding: high speeds with HSS or carbide, short broken chips, excellent surface and long tool life — the benchmark free-cutting steel for automatic lathes.
Can 11SMnPb30-CR be welded?
Not readily — weldability is rated not recommended (12/100). Not recommended — high sulphur and lead cause hot cracking and porosity; if unavoidable, use low-hydrogen filler, preheat and fume extraction for Pb.
What surface finishes work on 11SMnPb30-CR?
No anodizing; protect by zinc or Zn-Ni electroplating, phosphating, black oxide or oiling. Case-carbonitriding or salt-bath nitrocarburising can be applied for wear surfaces.
Can 11SMnPb30-CR be formed, bent or molded?
Poor cold formability and bendability due to MnS/Pb inclusions; only light cold heading or staking in the annealed condition, hot forming above ~1150 °C with care.
What is the maximum service temperature of 11SMnPb30-CR?
11SMnPb30-CR 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.
What is the difference between 11SMnPb30-HR and 11SMnPb30-SH?
HR is the default condition — cheapest bar form for large diameters or when parts are fully machined from oversize stock. SH: pick when higher yield strength / straightness is needed for slender turned or ground shafts. Yield strength is 260 MPa in HR versus 550 MPa in SH.
Can FabDigit make parts in 11SMnPb30-CR?
Yes — 11SMnPb30-CR is available for CNC machining with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- EN 10087 — Free-cutting steels: technical delivery conditions — CEN (1998)
- EN 10277-3 — Bright steel products: free-cutting steels — CEN (2008)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- ASM Handbook Vol.16 — Machining (machinability ratings) — ASM International (1989)
- Bright bar 1.0718 free-cutting steel data — European bright bar 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.