Steel 1137
AISI/SAE 1137 · UNS G11370
1137 (UNS G11370) is a medium-carbon, high-manganese resulfurized free-machining steel whose manganese sulfide inclusions break chips and give a machinability rating near 70 % of AISI 1212.
Values for the HR condition
1137 tempers and conditions
1137 is supplied in 9 conditions, soft to hard. HR 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 |
|---|---|---|---|---|---|---|
full anneal ~790 °C, furnace cooled | Softest condition; pick when maximum ductility for cold heading/bending or a stress-free blank before hardening is needed. | 345 | 585 | 28 | 174 HB | — |
HRDefault Hot rolled | Standard stocked condition for large-diameter screw-machine and forging stock; lowest cost. | 380 | 620 | 15 | 179 HB | — |
Normalized | Uniform fine pearlitic structure after forging; better toughness and consistency than as-rolled at similar strength. | 400 | 670 | 22 | 197 HB | — |
Stress relieved | Cold drawn then ~500 °C stress relief to reduce distortion during heavy one-side machining; slightly lower yield than plain CD. | 550 | 690 | 13 | 14 HRC | 10 % IACS |
Cold rolled | Cold-rolled flats and special sections; properties similar to cold drawn round bar, choose for flat/hex stock with bright surface. | 600 | 705 | 11 | 16 HRC | 10 % IACS |
Cold drawn | Most-used bar condition for automatic-lathe parts: tight tolerance, bright finish, higher strength and better chip control. | 620 | 725 | 10 | 217 HB | — |
water/oil quench + high temper (~620 °C) | Moderate-strength tough condition for shafts and studs that still need reasonable machining after heat treat. | 620 | 810 | 22 | 24 HRC | — |
quench + temper ~540 °C | Standard machine-shaft hardness band; good balance of strength, wear and remaining machinability. | 790 | 965 | 17 | 30 HRC | — |
quench + temper ~430–480 °C | Highest practical Q&T band for 1137 where wear resistance matters more than toughness; machine before hardening. | 980 | 1,150 | 13 | 35 HRC | 9 % IACS |
What is 1137?
1137 (UNS G11370) is a medium-carbon, high-manganese resulfurized free-machining steel whose manganese sulfide inclusions break chips and give a machinability rating near 70 % of AISI 1212. It is used for high-volume turned parts that need moderate strength, and is stocked as hot-rolled, cold-rolled and cold-drawn bar in annealed, normalized and quenched-and-tempered conditions from 22–26 HRC up to 33–38 HRC. Default cold-drawn values are about 380 MPa yield, 620 MPa tensile, 15 % elongation and 179 HB. The sulfur content makes it effectively unweldable and reduces transverse ductility and polishability; use 1141 or 1144 for higher strength, or 1018 where welding is required. 1137 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F). 1137 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 620 MPa (89.9 ksi) — weaker than 68% of steel grades. Elongation at break is 15% and the elastic modulus is 205 GPa (29.7 Msi).
What is 1137 used for?
- Screw machine parts
- Shafts and axles
- Studs, bolts and threaded components
- Pins and bushings
- Couplings and collars
- Induction-hardened gears and splines
- Hydraulic and valve fittings
Advantages
- Easy to machine — 70/100, better than 96% of steel grades
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
- High electrical conductivity — 10 % IACS, better than 83% of steel grades
- Conducts heat well — 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades
Limitations
- Hard to polish — 40/100, worse than 96% of steel grades
- Difficult to weld — 25/100, worse than 77% of steel grades
1137 properties
Typical room-temperature values for 1137-HR; bars are the position among steel grades.
Physical3
1137 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical13
1137 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 620 MPa (89.9 ksi) — weaker than 68% of steel grades. Elongation at break is 15% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
1137 is rated for continuous service to 400°C (752 °F). It conducts heat at 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades. Thermal expansion is 11.7 µm/m·K (6.5 µin/in·°F).
Electrical3
1137 conducts electricity at 10 % IACS, better than 83% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (9/100), worse than 98% of steel grades.
Sustainability4
Producing a kilogram of 1137 takes about 25 MJ of energy and emits 1.9 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 40%.
Manufacturability7
1137's machinability is very good (70/100, better than 96% of steel grades); weldability poor (25/100); 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. 1137 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 1137
Is 1137 easy to machine?
Excellent free-cutting behaviour (≈70–72 % of 1212); MnS breaks chips, run high feeds with carbide and sulfur-bearing cutting oil.
Can 1137 be welded?
Not recommended — high sulfur plus 0.35 %C causes hot cracking and porosity; if unavoidable, preheat 200–260 °C, low-hydrogen filler, post-weld stress relief.
Can 1137 be formed, bent or molded?
Poor transverse cold formability due to sulfide stringers; bend along the rolling direction with generous radii or hot form at 1000–1200 °C.
Manufacturability
The process limits FabDigit applies to 1137. Every 1137 part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
CNC machining
| Machinability | Excellent70 / 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 |
1137 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 |
|---|---|---|
| C | 0.32 – 0.39 | 0.36 |
| Mn | 1.35 – 1.65 | 1.5 |
| Sresulfurized for free machining | 0.08 – 0.13 | 0.1 |
| P | ≤ 0.04 | 0.02 |
| Sinot specified in SAE J403 for resulfurized grades; typical killed-steel level | ≤ 0.3 | 0.2 |
| Fe | balance |
What surface finishes work on 1137?
Rusts quickly — protect with oil, phosphate, black oxide, zinc or chrome plating; can be induction hardened or nitrided for wear surfaces, but poor for mirror polishing.
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 1137 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- G11370
How much does 1137 cost?
1137 is a budget-cost steel ($), cheaper than about 90% 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.
1137 — frequently asked
What is 1137 used for?
1137 is typically used for screw machine parts, shafts and axles, studs, bolts and threaded components, pins and bushings, couplings and collars and induction-hardened gears and splines. In short: resulfurized machining bar.
What is the yield strength of 1137?
1137 has a typical yield strength of 380 MPa (55.1 ksi) and a tensile strength of 620 MPa (89.9 ksi) — weaker than 68% of steel grades. Strength varies by condition: see the 9 listed tempers.
Is 1137 easy to machine?
Yes — machinability is rated very good (70/100, better than 96% of steel grades). Excellent free-cutting behaviour (≈70–72 % of 1212); MnS breaks chips, run high feeds with carbide and sulfur-bearing cutting oil.
Can 1137 be welded?
Not readily — weldability is rated poor (25/100). Not recommended — high sulfur plus 0.35 %C causes hot cracking and porosity; if unavoidable, preheat 200–260 °C, low-hydrogen filler, post-weld stress relief.
What surface finishes work on 1137?
Rusts quickly — protect with oil, phosphate, black oxide, zinc or chrome plating; can be induction hardened or nitrided for wear surfaces, but poor for mirror polishing.
Can 1137 be formed, bent or molded?
Poor transverse cold formability due to sulfide stringers; bend along the rolling direction with generous radii or hot form at 1000–1200 °C.
What is the maximum service temperature of 1137?
1137 is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1137-HR and 1137-CD?
HR is the default condition — standard stocked condition for large-diameter screw-machine and forging stock; lowest cost. CD: most-used bar condition for automatic-lathe parts: tight tolerance, bright finish, higher strength and better chip control. Yield strength is 380 MPa in HR versus 620 MPa in CD.
How much does 1137 cost?
1137 is a budget-cost steel ($), cheaper than about 90% 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 1137?
Yes — 1137 is available for CNC machining; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- SAE J403 — Chemical Compositions of SAE Carbon Steels — SAE International (2014)
- SAE J1397 — Estimated Mechanical Properties of Steel Bars — SAE International (2018)
- ASTM A29/A29M — Steel Bars, Carbon and Alloy, Hot-Wrought — ASTM (2020)
- ASTM A108 — Steel Bar, Carbon and Alloy, Cold-Finished — ASTM (2018)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.16 — Machining — ASM International (1989)
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.