Steel 1141 · hardness band
Steel 1141 QT_33_38HRC
Properties of the QT_33_38HRC condition, compared with the other 1141 tempers.
Highest practical through-hardened level for 1141 in small sections; pick for wear-loaded pins and studs, accepting reduced toughness.
What is 1141 QT_33_38HRC?
1141 QT_33_38HRC is 1141 heat treated to QT_33_38HRC — highest practical through-hardened level for 1141 in small sections; pick for wear-loaded pins and studs, accepting reduced toughness. 1141 QT_33_38HRC has a yield strength of 1,000 MPa (145 ksi) and a tensile strength of 1,150 MPa (167 ksi) — stronger than 92% of steel grades. Elongation at break is 12% and the elastic modulus is 200 GPa (29 Msi). 1141 QT_33_38HRC 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). HR is the default condition FabDigit quotes; QT_33_38HRC is available on request or by drawing note.
Advantages
- Easy to machine — 68/100, better than 95% of steel grades
- High strength — 1,000 MPa (145 ksi), better than 92% 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
Limitations
- Limited ductility — 12%, worse than 84% of steel grades
- Difficult to weld — 25/100, worse than 77% of steel grades
1141 QT_33_38HRC properties
Typical room-temperature values for 1141 QT_33_38HRC — 10 properties are specific to this condition; the rest are grade-level values shared by every 1141 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
1141 QT_33_38HRC 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
1141 QT_33_38HRC has a yield strength of 1,000 MPa (145 ksi) and a tensile strength of 1,150 MPa (167 ksi) — stronger than 92% of steel grades. Elongation at break is 12% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
1141 QT_33_38HRC is rated for continuous service to 350°C (662 °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
1141 QT_33_38HRC 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 1141 QT_33_38HRC takes about 25 MJ of energy and emits 1.9 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 30%.
Manufacturability6
1141 QT_33_38HRC's machinability is good (68/100, better than 95% of steel grades); weldability poor (25/100); formability fair (35/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 1141 tempers and conditions
1141 is also supplied in 8 other conditions. The full side-by-side table is on the 1141 overview.
- HRDefaultDefault, cheapest stock form; pick for machined parts that will be heat treated afterwards or where tolerances are cut on all surfaces.360 MPa yield · 192 HB
- QT_33_38HRCHighest practical through-hardened level for 1141 in small sections; pick for wear-loaded pins and studs, accepting reduced toughness.1,000 MPa yield · 35 HRC
- QT_28_32HRCMost common heat-treated spec for 1141 machined shafts, axles and hydraulic components — good strength with acceptable machinability.830 MPa yield · 30 HRC
- QT_22_26HRCTough general-purpose heat-treated condition for shafts and studs where ductility matters more than peak strength.690 MPa yield · 24 HRC
- CDMost common commercial condition for screw-machine work: higher yield, bright surface and close diameter tolerance straight from the bar.640 MPa yield · 217 HB
- IHPick for shafts and splines needing a wear-resistant case and high bending fatigue strength while keeping a ductile core; 1141's Mn level suits induction practice.600 MPa yield · 54 HRC
- CRChoose for a smooth as-supplied surface and tighter size on flats/strip where a cold-drawn round is not offered.585 MPa yield · 212 HB
- NormalizedUse to homogenize structure and improve toughness/ductility uniformity before machining or as a final condition for moderately loaded parts.405 MPa yield · 201 HB
- AnnealedPick when maximum ductility and lowest hardness are needed for heavy cold forming or to relieve prior cold work.350 MPa yield · 170 HB
Working with 1141 QT_33_38HRC
Is 1141 easy to machine?
Excellent free-cutting behaviour (≈70 % of 1212) with short chips and good surface finish; run high feeds with carbide and expect good tool life, but avoid it where transverse toughness or leak-tight sealing surfaces are critical.
Can 1141 be welded?
Not recommended — 0.4 % C plus 0.10 % S gives hot cracking and hard HAZ; if unavoidable, preheat 200–300 °C, use low-hydrogen consumables and post-weld stress relieve.
Can 1141 be formed, bent or molded?
Limited cold formability; bend generously (≥3t) in annealed condition, or hot form at 1100–1200 °C and avoid working below ~850 °C because sulfides cause hot shortness.
What surface finishes work on 1141?
No corrosion resistance bare — specify oil, black oxide, phosphate, zinc or Cr-free zinc-nickel plating; grinding and hard chrome are common on induction-hardened shaft journals; sulfide stringers can leave micro-pits on high-polish surfaces.
1141 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 | 0.37 – 0.45 | 0.41 |
| Mn | 1.35 – 1.65 | 1.5 |
| P | ≤ 0.04 | 0.02 |
| Sresulfurized for machinability | 0.08 – 0.13 | 0.1 |
| Sinot specified in SAE 1141; typical residual 0.15–0.35 for killed steel | ≈ 0.22 | 0.22 |
| Fe | balance | — |
1141 QT_33_38HRC — frequently asked
What is 1141 QT_33_38HRC used for?
1141 QT_33_38HRC is typically used for tie rods, studs and splined shafts. In short: high-strength fatigue resistant.
What is the yield strength of 1141 QT_33_38HRC?
1141 QT_33_38HRC has a typical yield strength of 1,000 MPa (145 ksi) and a tensile strength of 1,150 MPa (167 ksi) — stronger than 92% of steel grades. Strength varies by condition: see the 9 listed tempers.
Is 1141 QT_33_38HRC easy to machine?
Reasonably — machinability is rated good (68/100, better than 95% of steel grades). Excellent free-cutting behaviour (≈70 % of 1212) with short chips and good surface finish; run high feeds with carbide and expect good tool life, but avoid it where transverse toughness or leak-tight sealing surfaces are critical.
Can 1141 QT_33_38HRC be welded?
Not readily — weldability is rated poor (25/100). Not recommended — 0.4 % C plus 0.10 % S gives hot cracking and hard HAZ; if unavoidable, preheat 200–300 °C, use low-hydrogen consumables and post-weld stress relieve.
What surface finishes work on 1141 QT_33_38HRC?
No corrosion resistance bare — specify oil, black oxide, phosphate, zinc or Cr-free zinc-nickel plating; grinding and hard chrome are common on induction-hardened shaft journals; sulfide stringers can leave micro-pits on high-polish surfaces.
Can 1141 QT_33_38HRC be formed, bent or molded?
Limited cold formability; bend generously (≥3t) in annealed condition, or hot form at 1100–1200 °C and avoid working below ~850 °C because sulfides cause hot shortness.
What is the maximum service temperature of 1141 QT_33_38HRC?
1141 QT_33_38HRC 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 1141-HR and 1141-CD?
HR is the default condition — default, cheapest stock form; pick for machined parts that will be heat treated afterwards or where tolerances are cut on all surfaces. CD: most common commercial condition for screw-machine work: higher yield, bright surface and close diameter tolerance straight from the bar. Yield strength is 360 MPa in HR versus 640 MPa in CD.
Can FabDigit make parts in 1141 QT_33_38HRC?
Yes — 1141 QT_33_38HRC is available for CNC machining with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- 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)
- SAE J403 — Chemical Compositions of SAE Carbon Steels — SAE International (2014)
- SAE J404 / J1268 (hardenability of carbon and alloy steels) — SAE International (2018)
- ASM Handbook Vol. 1: Properties and Selection — Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol. 4: Heat Treating — ASM International (1991)
- GB/T 8731 (comparable Y40Mn grade) — SAC (2008)
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.