Steel 1144
AISI/SAE 1144 · UNS G11440 · EN 1.0727, 44SMn28 · also Stressproof
1144 is a resulfurized medium-carbon free-machining steel (G11440; EN 10087 44SMn28 / 1.0762), commonly stocked cold-drawn and stress-relieved as Stressproof bar.
Values for the HR condition
1144 tempers and conditions
1144 is supplied in 8 conditions, soft to hard. HR is the default FabDigit quotes; the values on this page are for it.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
spheroidize/full annealed bar | Softest condition; choose for deep machining, cold forming or before hardening. | 345 | 585 | 20 | 167 HB | — |
HRDefault Hot rolled | Lowest-cost stock size for parts that will be fully machined or later heat treated. | 400 | 670 | 15 | 13 HRC | 9.5 % IACS |
austenitized ~900 °C, air cooled | Use to refine grain and homogenize structure after hot working, before machining or hardening. | 420 | 670 | 21 | 13 HRC | 9.5 % IACS |
Cold rolled | Cold-reduced flat/shaped stock where a bright, dimensionally accurate as-supplied surface is needed. | 600 | 700 | 10 | 17 HRC | 9.5 % IACS |
Cold drawn | Standard cold-finished bar: tighter tolerance, bright surface and higher yield than hot rolled. | 620 | 705 | 10 | 212 HB | — |
Induction hardened | For shafts and pins needing a wear-resistant, fatigue-strong skin over a tough cold-drawn core. | 655 | 790 | 10 | 54 HRC | 8.5 % IACS |
Cold Drawn, Stress Relieved | Pick when a machined shaft must stay straight after heavy stock removal and needs ~690 MPa yield without heat treatment. | 690 | 790 | 12 | 21 HRC | — |
quenched and tempered | Oil quench from ~845 °C and temper ~540 °C when higher core strength and wear resistance are required. | 830 | 965 | 13 | 30 HRC | — |
What is 1144?
1144 is a resulfurized medium-carbon free-machining steel (G11440; EN 10087 44SMn28 / 1.0762), commonly stocked cold-drawn and stress-relieved as Stressproof bar. Engineers choose it for shafts that need strength together with fast turning: the default condition gives 400 MPa yield, 670 MPa tensile, 15 % elongation, 197 HB (93 HRB) and a machinability score of 78, about 80 % of 1212. The 0.44 % C combined with high sulphur makes it effectively unweldable, weak in transverse ductility and without corrosion resistance. Choose 1045 when welding is required, or 1215 when strength is secondary. 1144 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). 1144 has a yield strength of 400 MPa (58 ksi) and a tensile strength of 670 MPa (97.2 ksi) — weaker than 60% of steel grades. Elongation at break is 15% and the elastic modulus is 205 GPa (29.7 Msi).
What is 1144 used for?
- Shafts
- Industrial spindles
- Cam followers
Advantages
- Easy to machine — 78/100, better than 97% of steel grades
- Conducts heat well — 51 W/m·K (29.5 BTU/hr·ft·°F), better than 92% of steel grades
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
- High electrical conductivity — 9.5 % IACS, better than 75% of steel grades
Limitations
- Hard to polish — 40/100, worse than 96% of steel grades
- Low fracture toughness — 50 MPa·√m (45.5 ksi·√in), worse than 86% of steel grades
- Difficult to weld — 20/100, worse than 84% of steel grades
1144 properties
Typical room-temperature values for 1144-HR; bars are the position among steel grades.
Physical3
1144 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).
Mechanical17
1144 has a yield strength of 400 MPa (58 ksi) and a tensile strength of 670 MPa (97.2 ksi) — weaker than 60% of steel grades. Elongation at break is 15% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
1144 is rated for continuous service to 400°C (752 °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
1144 conducts electricity at 9.5 % IACS, better than 75% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.
Sustainability4
Producing a kilogram of 1144 takes about 25 MJ of energy and emits 1.9 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 35%.
Manufacturability6
1144's machinability is very good (78/100, better than 97% of steel grades); weldability poor (20/100); formability poor (25/100).
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. 1144 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 1144
Is 1144 easy to machine?
One of the best-machining medium carbon steels (~80 % of 1212): high speeds, chip-breaking MnS inclusions, long tool life; keep feeds up to avoid rubbing.
Can 1144 be welded?
Not recommended — 0.44 C plus 0.3 % S invites hot cracking and porosity; if unavoidable, preheat 200–300 °C, low-hydrogen filler and post-weld stress relief.
Can 1144 be formed, bent or molded?
Poor cold formability, especially transverse; bend only in the annealed condition with generous radii, or hot form at 1050–1200 °C.
Manufacturability
The process limits FabDigit applies to 1144. Every 1144 part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
CNC machining
| Machinability | Excellent78 / 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 |
1144 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 grade 1144 | 0.4 – 0.48 | 0.44 |
| Mn | 1.35 – 1.65 | 1.5 |
| SMnS inclusions give free-machining behaviour | 0.24 – 0.33 | 0.28 |
| P | ≤ 0.04 | 0.02 |
| Sinot normally specified for resulfurized grades | ≤ 0.1 | 0.05 |
| Fe | balance |
What surface finishes work on 1144?
Rusts readily — specify black oxide, phosphate + oil, zinc or hard chrome plating; MnS stringers limit mirror polishing and can leave pits after plating.
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 1144 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- G11440
- EN / DIN / Werkstoff-Nr.
- 1.072744SMn281.076210087
- Trade names
- Stressproof
How much does 1144 cost?
1144 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.
1144 — frequently asked
What is 1144 used for?
1144 is typically used for shafts, industrial spindles and cam followers. In short: resulfurized machining bar.
What is the yield strength of 1144?
1144 has a typical yield strength of 400 MPa (58 ksi) and a tensile strength of 670 MPa (97.2 ksi) — weaker than 60% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is 1144 easy to machine?
Yes — machinability is rated very good (78/100, better than 97% of steel grades). One of the best-machining medium carbon steels (~80 % of 1212): high speeds, chip-breaking MnS inclusions, long tool life; keep feeds up to avoid rubbing.
Can 1144 be welded?
Not readily — weldability is rated poor (20/100). Not recommended — 0.44 C plus 0.3 % S invites hot cracking and porosity; if unavoidable, preheat 200–300 °C, low-hydrogen filler and post-weld stress relief.
What surface finishes work on 1144?
Rusts readily — specify black oxide, phosphate + oil, zinc or hard chrome plating; MnS stringers limit mirror polishing and can leave pits after plating.
Can 1144 be formed, bent or molded?
Poor cold formability, especially transverse; bend only in the annealed condition with generous radii, or hot form at 1050–1200 °C.
What is the maximum service temperature of 1144?
1144 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 1144-HR and 1144 CD-SR?
HR is the default condition — lowest-cost stock size for parts that will be fully machined or later heat treated. CD-SR: pick when a machined shaft must stay straight after heavy stock removal and needs ~690 MPa yield without heat treatment. Yield strength is 400 MPa in HR versus 690 MPa in CD-SR.
How much does 1144 cost?
1144 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 1144?
Yes — 1144 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
- ASTM A29/A29M Steel Bars, Carbon and Alloy, Hot-Wrought — ASTM International (2020)
- SAE J403 Chemical Compositions of SAE Carbon Steels — SAE International (2014)
- SAE J1397 Estimated Mechanical Properties of Steel Bars — SAE International (2009)
- EN 10087 Free-cutting steels (44SMn28, 1.0727) — CEN (2018)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- ASM Handbook Vol.16 — Machining — ASM International (1989)
- Stressproof cold drawn stress relieved bar data — Niagara LaSalle / bar producers (2022)
- GB/T 8731 (Y45Mn) — SAC (2008)
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.