Steel 1040 · heat-treated state
Steel 1040 Q&T
Properties of the Q&T condition, compared with the other 1040 tempers.
Pick this quenched (845 °C, water) and ~540 °C tempered condition for shafts and fasteners: 434 MPa yield with retained toughness and easy machining at roughly 185–200 HB.
What is 1040 Q&T?
1040 Q&T is 1040 heat treated to Q&T — pick this quenched (845 °C, water) and ~540 °C tempered condition for shafts and fasteners: 434 MPa yield with retained toughness and easy machining at roughly 185–200 HB. 1040 Q&T has a yield strength of 434 MPa (62.9 ksi) and a tensile strength of 634 MPa (92 ksi) — stronger than 50% of steel grades. Elongation at break is 29% and the elastic modulus is 205 GPa (29.7 Msi). 1040 Q&T 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; Q&T is available on request or by drawing note.
Advantages
- Conducts heat well — 51 W/m·K (29.5 BTU/hr·ft·°F), better than 92% of steel grades
- Ductile — tolerates forming and impact — 29%, better than 91% of steel grades
- High electrical conductivity — 10 % IACS, better than 82% of steel grades
Limitations
- Low fracture toughness — 65 MPa·√m (59.2 ksi·√in), worse than 76% of steel grades
1040 Q&T properties
Typical room-temperature values for 1040 Q&T — 13 properties are specific to this condition; the rest are grade-level values shared by every 1040 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
1040 Q&T 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
1040 Q&T has a yield strength of 434 MPa (62.9 ksi) and a tensile strength of 634 MPa (92 ksi) — stronger than 50% of steel grades. Elongation at break is 29% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
1040 Q&T 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 11.5 µm/m·K (6.39 µin/in·°F).
Electrical3
1040 Q&T conducts electricity at 10 % IACS, better than 82% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 87% of steel grades.
Sustainability4
Producing a kilogram of 1040 Q&T takes about 25 MJ of energy and emits 2.1 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 25%.
Manufacturability6
1040 Q&T's machinability is good (55/100, better than 62% of steel grades); weldability fair (45/100); formability fair (45/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 1040 tempers and conditions
1040 is also supplied in 9 other conditions. The full side-by-side table is on the 1040 overview.
- HRDefaultCheapest general-purpose stock for shafting, plate and structural machine parts where tolerance and surface finish are not critical.415 MPa yield · 201 HB
- Q&T 25-30 HRCHighest strength through-hardened condition for small sections (pins, keys, links) where toughness demands are moderate.593 MPa yield · 27 HRC
- CDPick for close-tolerance bright bar, higher yield strength and improved chip control on automatic lathes.565 MPa yield · 190 HB
- Q&T 20-24 HRCChoose quenching with a 425 °C temper when about 758 MPa tensile is needed but the part must still be turned and drilled easily at 20–24 HRC.517 MPa yield · 22 HRC
- CRCold-rolled strip/sheet for stamped and formed parts needing better finish and thickness tolerance than hot rolled.490 MPa yield · 190 HB
- IHChoose when journals, splines or cam faces need 50+ HRC wear resistance while the core stays tough.450 MPa yield · 55 HRC
- Q&TPick this quenched (845 °C, water) and ~540 °C tempered condition for shafts and fasteners: 434 MPa yield with retained toughness and easy machining at roughly 185–200 HB.434 MPa yield · 12 HRC
- NormalizedUniform fine pearlitic structure with the best toughness/strength balance of the untempered conditions; standard pre-machining condition for forgings.374 MPa yield · 170 HB
- AnnealedSoftest condition — choose for maximum ductility before cold forming, deep machining or further heat treatment.353 MPa yield · 149 HB
- Q&T 88-92 HRBSoftest Q&T level — maximum ductility and impact toughness with a tempered structure, used for heavily cold-worked or welded assemblies.345 MPa yield · 170 HB
Working with 1040 Q&T
Is 1040 easy to machine?
Machines readily at ~60 % of 1212; best chip control in cold-drawn or 180–220 HB Q&T condition, use rigid setups and coolant since 0.40 % C is gummier than free-cutting grades.
Can 1040 be welded?
Weldable with low-hydrogen SMAW/GMAW but preheat 150–260 °C, control interpass temperature and stress-relieve/temper after welding to avoid martensitic HAZ cracking.
Can 1040 be formed, bent or molded?
Cold form only in annealed or normalized condition with generous bend radii; hot forge 1100–1230 °C and normalize afterwards.
What surface finishes work on 1040?
No inherent corrosion resistance — specify paint, zinc/chrome plating, phosphate+oil, black oxide or nitrocarburizing; polishes to a good bright finish but rusts quickly if unprotected.
1040 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 | 0.6 – 0.9 | 0.75 |
| P | ≤ 0.03 | 0.02 |
| S | ≤ 0.05 | 0.03 |
| Sinot specified in SAE J403 for bar; typical mill practice / required by JIS S40C and EN 1.0511 | 0.15 – 0.35 | 0.25 |
| Fe | balance | — |
1040 Q&T — frequently asked
What is 1040 Q&T used for?
1040 Q&T is typically used for crankshafts, couplings and shafts. In short: excellent wear resistance.
What is the yield strength of 1040 Q&T?
1040 Q&T has a typical yield strength of 434 MPa (62.9 ksi) and a tensile strength of 634 MPa (92 ksi) — stronger than 50% of steel grades. Strength varies by condition: see the 10 listed tempers.
Is 1040 Q&T easy to machine?
Reasonably — machinability is rated good (55/100, better than 62% of steel grades). Machines readily at ~60 % of 1212; best chip control in cold-drawn or 180–220 HB Q&T condition, use rigid setups and coolant since 0.40 % C is gummier than free-cutting grades.
Can 1040 Q&T be welded?
With care — weldability is rated fair (45/100). Weldable with low-hydrogen SMAW/GMAW but preheat 150–260 °C, control interpass temperature and stress-relieve/temper after welding to avoid martensitic HAZ cracking.
What surface finishes work on 1040 Q&T?
No inherent corrosion resistance — specify paint, zinc/chrome plating, phosphate+oil, black oxide or nitrocarburizing; polishes to a good bright finish but rusts quickly if unprotected.
Can 1040 Q&T be formed, bent or molded?
Cold form only in annealed or normalized condition with generous bend radii; hot forge 1100–1230 °C and normalize afterwards.
What is the maximum service temperature of 1040 Q&T?
1040 Q&T 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 1040-HR and 1040-CD?
HR is the default condition — cheapest general-purpose stock for shafting, plate and structural machine parts where tolerance and surface finish are not critical. CD: pick for close-tolerance bright bar, higher yield strength and improved chip control on automatic lathes. Yield strength is 415 MPa in HR versus 565 MPa in CD.
Can FabDigit make parts in 1040 Q&T?
Yes — 1040 Q&T is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- SAE J403 — Chemical Compositions of SAE Carbon Steels — SAE International (2014)
- ASTM A29/A29M — Steel Bars, Carbon and Alloy, Hot-Wrought — ASTM (2020)
- ASTM A108 — Steel Bar, Carbon and Alloy, Cold-Finished — ASTM (2018)
- JIS G 4051 — Carbon steels for machine structural use (S40C) — JSA (2016)
- EN 10083-2 / EN 10277 — Steels for quenching and tempering (C40, 1.0511) — CEN (2006)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- ASM Handbook Vol.19 — Fatigue and Fracture — ASM International (1996)
- Metals Handbook / Bringas 'Handbook of Comparative World Steel Standards' — ASTM (2004)
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.