Steel 11SMn37 · supply condition · default condition
Steel 11SMn37-HR
Properties of the HR condition, compared with the other 11SMn37 tempers.
Cheapest form, black scaled surface and loose tolerance — pick when the part will be fully machined from oversize stock.
What is 11SMn37-HR?
11SMn37-HR is 11SMn37 supplied in the HR condition — cheapest form, black scaled surface and loose tolerance — pick when the part will be fully machined from oversize stock. 11SMn37-HR has a yield strength of 280 MPa (40.6 ksi) and a tensile strength of 420 MPa (60.9 ksi) — weaker than 90% of steel grades. Elongation at break is 22% and the elastic modulus is 205 GPa (29.7 Msi). 11SMn37-HR has a density of 7.87 g/cm³ (0.284 lb/in³), heavier than 91% of steel grades. It melts at 1,420°C (2,588 °F).
Advantages
- Easy to machine — 88/100, better than 99% of steel grades
- Conducts heat well — 51 W/m·K (29.5 BTU/hr·ft·°F), better than 92% of steel grades
- High electrical conductivity — 10.5 % IACS, better than 89% of steel grades
Limitations
- Hard to polish — 40/100, worse than 96% of steel grades
- Difficult to weld — 15/100, worse than 91% of steel grades
- Low strength — 280 MPa (40.6 ksi), worse than 90% of steel grades
11SMn37-HR properties
Typical room-temperature values for 11SMn37-HR — 13 properties are specific to this condition; the rest are grade-level values shared by every 11SMn37 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
11SMn37-HR has a density of 7.87 g/cm³ (0.284 lb/in³), heavier than 91% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical14
11SMn37-HR has a yield strength of 280 MPa (40.6 ksi) and a tensile strength of 420 MPa (60.9 ksi) — weaker than 90% of steel grades. Elongation at break is 22% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
11SMn37-HR is rated for continuous service to 350°C (662 °F). It conducts heat at 51 W/m·K (29.5 BTU/hr·ft·°F), better than 92% of steel grades. Thermal expansion is 11.7 µm/m·K (6.5 µin/in·°F).
Electrical3
11SMn37-HR conducts electricity at 10.5 % IACS, better than 89% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (8/100), worse than 99% of steel grades.
Sustainability4
Producing a kilogram of 11SMn37-HR takes about 25 MJ of energy and emits 2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 35%.
Manufacturability7
11SMn37-HR's machinability is excellent (88/100, better than 99% of steel grades); weldability poor (15/100); formability fair (40/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 11SMn37 tempers and conditions
11SMn37 is also supplied in 5 other conditions. The full side-by-side table is on the 11SMn37 overview.
- HRDefaultCheapest form, black scaled surface and loose tolerance — pick when the part will be fully machined from oversize stock.280 MPa yield · 125 HB
- SHChoose when parts are machined off-centre or slender and must stay straight after stock removal.480 MPa yield · 180 HB
- CDStandard stock condition for automatic-lathe work: best surface, tight tolerance (h9/h11) and highest strength.420 MPa yield · 170 HB
- CRCold-rolled flats, hexagons and shaped sections where a bright, dimensionally accurate profile is needed.410 MPa yield · 165 HB
- AnnealedSoftest condition, used when heavy cold heading, staking or deep upsetting follows machining.250 MPa yield · 118 HB
Working with 11SMn37-HR
Is 11SMn37 easy to machine?
Benchmark free-cutting steel: run high speeds with sharp positive-rake carbide or HSS, light feeds give short chips; expect ~30–40 % higher metal-removal rates than 1.0402/C22.
Can 11SMn37 be welded?
Not recommended — 0.32–0.42 % S causes hot cracking and porosity; if unavoidable use low-hydrogen consumables, preheat and accept reduced joint properties.
Can 11SMn37 be formed, bent or molded?
Only light cold forming (knurling, staking, small upsets); transverse bending and heavy heading crack along the MnS stringers — use annealed stock and generous radii.
What surface finishes work on 11SMn37?
Zinc or Zn-Ni plating, black oxide, phosphate or nickel are standard; polishing shows inclusion pull-out, and case hardening is possible (carbonitriding) but gives shallow, uneven cases.
11SMn37 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 | 0.09 |
| Sikept low to preserve machinability | ≤ 0.05 | 0.03 |
| Mnforms MnS chip breakers | 1 – 1.5 | 1.25 |
| Pintentionally high | ≤ 0.11 | 0.07 |
| Sfree-cutting addition | 0.32 – 0.42 | 0.37 |
| Fe | balance | — |
11SMn37-HR — frequently asked
What is 11SMn37-HR used for?
11SMn37-HR is typically used for screw machine turned parts, fasteners and threaded inserts, hydraulic and pneumatic fittings, bushings and spacers, small shafts and pins and instrument and connector bodies. In short: free-machining sulfurized bar.
What is the yield strength of 11SMn37-HR?
11SMn37-HR has a typical yield strength of 280 MPa (40.6 ksi) and a tensile strength of 420 MPa (60.9 ksi) — weaker than 90% of steel grades. Strength varies by condition: see the 6 listed tempers.
Is 11SMn37-HR easy to machine?
Yes — machinability is rated excellent (88/100, better than 99% of steel grades). Benchmark free-cutting steel: run high speeds with sharp positive-rake carbide or HSS, light feeds give short chips; expect ~30–40 % higher metal-removal rates than 1.0402/C22.
Can 11SMn37-HR be welded?
Not readily — weldability is rated poor (15/100). Not recommended — 0.32–0.42 % S causes hot cracking and porosity; if unavoidable use low-hydrogen consumables, preheat and accept reduced joint properties.
What surface finishes work on 11SMn37-HR?
Zinc or Zn-Ni plating, black oxide, phosphate or nickel are standard; polishing shows inclusion pull-out, and case hardening is possible (carbonitriding) but gives shallow, uneven cases.
Can 11SMn37-HR be formed, bent or molded?
Only light cold forming (knurling, staking, small upsets); transverse bending and heavy heading crack along the MnS stringers — use annealed stock and generous radii.
What is the maximum service temperature of 11SMn37-HR?
11SMn37-HR is rated for continuous use to about 350°C (662 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 11SMn37-HR and 11SMn37-SH?
HR is the default condition — cheapest form, black scaled surface and loose tolerance — pick when the part will be fully machined from oversize stock. SH: choose when parts are machined off-centre or slender and must stay straight after stock removal. Yield strength is 280 MPa in HR versus 480 MPa in SH.
Can FabDigit make parts in 11SMn37-HR?
Yes — 11SMn37-HR 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, and High-Performance Alloys — ASM International (1990)
- Stahlschlüssel / Key to Steel — 1.0736 — Verlag Stahlschlüssel Wegst (2019)
- Free-cutting steel bright bar datasheets (11SMn37 / 11SMnPb37) — European bright bar producers (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.