Steel 1140
AISI/SAE 1140 · UNS G11400
1140 is a medium-carbon resulfurized free-machining steel (SAE/AISI 1140, UNS G11400) that carries about 0.40 % carbon for higher strength than low-carbon free-cutting grades while keeping good chip control.
Reference datasheet — 1140 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the CD condition
1140 tempers and conditions
1140 is supplied in 9 conditions, soft to hard. CD 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 |
|---|---|---|---|---|---|---|
Solution annealed | Softest, most stable condition — for deep boring, cold forming or before final hardening. | 310 | 560 | 24 | 156 HB | — |
Hot rolled | Lowest-cost condition for parts machined all over or for subsequent heat treatment. | 345 | 585 | 20 | 170 HB | — |
Normalized | Refines grain and homogenises hot-rolled bar before quench-and-temper or heavy machining. | 375 | 650 | 22 | 10 HRC | 10 % IACS |
Cold drawn, stress relieved | Use where cold-drawn strength is wanted but distortion during heavy one-side machining must be minimised. | 480 | 620 | 18 | 11 HRC | 10 % IACS |
CDDefault Cold drawn | Most stocked condition: higher yield strength, tight size tolerance and a bright, chip-friendly surface for screw-machine work. | 550 | 655 | 15 | 197 HB | — |
Induction hardened | Use when wear-resistant journal or spline surfaces are needed on a tough core. | 580 | 800 | 10 | 54 HRC | 9 % IACS |
oil quenched, high temper (≈620 °C) | Choose for shafts needing balanced strength and toughness that will still be machined after heat treatment. | 620 | 800 | 18 | 24 HRC | — |
oil quenched, tempered ≈540 °C | Standard through-hardened condition for medium-duty shafts, pins and couplings. | 790 | 950 | 15 | 30 HRC | — |
oil quenched, tempered ≈430 °C | Highest practical strength for 1140 sections; accept low ductility and difficult machining. | 1,030 | 1,180 | 12 | 38 HRC | — |
Supply forms, finishes and certifications
Ways 1140 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
TGP | Turned, ground and polished bar | Surface finish |
What is 1140?
1140 is a medium-carbon resulfurized free-machining steel (SAE/AISI 1140, UNS G11400) that carries about 0.40 % carbon for higher strength than low-carbon free-cutting grades while keeping good chip control. Engineers use it for turned and heat-treated shafting; it is available hot-rolled, cold-drawn, TGP, stress-relieved, annealed, normalized and in quenched-and-tempered ranges of 22–26, 28–32 and 35–40 HRC, plus induction-hardened. Cold-drawn bar shows about 550 MPa yield, 655 MPa tensile, 15 % elongation and 197 HB, with machinability 68. Weldability (30) and formability (30) are both low; 1141 or 1144 offer more strength, 1215 better machinability. 1140 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). 1140 has a yield strength of 550 MPa (79.8 ksi) and a tensile strength of 655 MPa (95 ksi) — stronger than 71% of steel grades. Elongation at break is 15% and the elastic modulus is 205 GPa (29.7 Msi).
What is 1140 used for?
- Shafts
- gears
- axles
- machined structural parts
Advantages
- Easy to machine — 68/100, better than 95% of steel grades
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
- Conducts heat well — 49 W/m·K (28.3 BTU/hr·ft·°F), better than 83% of steel grades
- High electrical conductivity — 10 % IACS, better than 83% of steel grades
Limitations
- Low fracture toughness — 50 MPa·√m (45.5 ksi·√in), worse than 86% of steel grades
1140 properties
Typical room-temperature values for 1140-CD; bars are the position among steel grades.
Physical3
1140 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).
Mechanical16
1140 has a yield strength of 550 MPa (79.8 ksi) and a tensile strength of 655 MPa (95 ksi) — stronger than 71% of steel grades. Elongation at break is 15% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
1140 is rated for continuous service to 400°C (752 °F). It conducts heat at 49 W/m·K (28.3 BTU/hr·ft·°F), better than 83% of steel grades. Thermal expansion is 11.7 µm/m·K (6.5 µin/in·°F).
Electrical3
1140 conducts electricity at 10 % IACS, better than 83% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.
Sustainability4
Producing a kilogram of 1140 takes about 25 MJ of energy and emits 1.9 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 35%.
Manufacturability7
1140's machinability is good (68/100, better than 95% of steel grades); weldability poor (30/100); formability poor (30/100).
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. 1140 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 1140
Is 1140 easy to machine?
Excellent free-machining behaviour (~70 % of 1212); run high speeds with positive-rake carbide, light feeds and sulfurized oil for good chip control and finish.
Can 1140 be welded?
Not recommended for structural welds — high sulfur promotes hot cracking and 0.40 % C needs 150–260 °C preheat plus post-weld stress relief; use low-hydrogen filler if unavoidable.
Can 1140 be formed, bent or molded?
Limited cold formability, especially transverse to the rolling direction; hot form at 1100–1200 °C and anneal before severe bending or heading.
1140 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 |
|---|---|---|
| CSAE J403 / ASTM A29 heat analysis | 0.37 – 0.44 | 0.4 |
| Mn | 0.7 – 1 | 0.85 |
| Sresulfurized for machinability | 0.08 – 0.13 | 0.1 |
| P | ≤ 0.04 | 0.02 |
| Sinot specified for resulfurized grades unless agreed (typ. 0.15–0.30 in Si-killed heats) | — | |
| Fe | balance |
What surface finishes work on 1140?
No inherent corrosion resistance — protect with oil, black oxide, phosphate, zinc or nickel plating; sulfide inclusions can leave micro-pits in high-gloss polished or plated surfaces.
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).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel 1140 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- G11400
How much does 1140 cost?
1140 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.
1140 — frequently asked
What is 1140 used for?
1140 is typically used for shafts, gears, axles and machined structural parts. In short: heat-treatable free-cutting bar; wide range of tempers; limited weldability.
What is the yield strength of 1140?
1140 has a typical yield strength of 550 MPa (79.8 ksi) and a tensile strength of 655 MPa (95 ksi) — stronger than 71% of steel grades. Strength varies by condition: see the 9 listed tempers.
Is 1140 easy to machine?
Reasonably — machinability is rated good (68/100, better than 95% of steel grades). Excellent free-machining behaviour (~70 % of 1212); run high speeds with positive-rake carbide, light feeds and sulfurized oil for good chip control and finish.
Can 1140 be welded?
Not readily — weldability is rated poor (30/100). Not recommended for structural welds — high sulfur promotes hot cracking and 0.40 % C needs 150–260 °C preheat plus post-weld stress relief; use low-hydrogen filler if unavoidable.
What surface finishes work on 1140?
No inherent corrosion resistance — protect with oil, black oxide, phosphate, zinc or nickel plating; sulfide inclusions can leave micro-pits in high-gloss polished or plated surfaces.
Can 1140 be formed, bent or molded?
Limited cold formability, especially transverse to the rolling direction; hot form at 1100–1200 °C and anneal before severe bending or heading.
What is the maximum service temperature of 1140?
1140 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 1140-CD and 1140-A?
CD is the default condition — most stocked condition: higher yield strength, tight size tolerance and a bright, chip-friendly surface for screw-machine work. A: softest, most stable condition — for deep boring, cold forming or before final hardening. Yield strength is 550 MPa in CD versus 310 MPa in A.
How much does 1140 cost?
1140 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.
Sources
- SAE J403 — Chemical Compositions of SAE Carbon Steels — SAE International (2014)
- ASTM A29/A29M — Steel Bars, Carbon and Alloy, Hot-Wrought, General Requirements — 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)
- ASM Handbook Vol.19 — Fatigue and Fracture — ASM International (1996)
- Mysteel / SMM · (2026)
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.