Steel 1090 · heat-treated state
Steel 1090 Q&T
Properties of the Q&T condition, compared with the other 1090 tempers.
General hardened-and-tempered condition for springs and high-strength wear parts needing some toughness.
What is 1090 Q&T?
1090 Q&T is 1090 heat treated to Q&T — general hardened-and-tempered condition for springs and high-strength wear parts needing some toughness. 1090 Q&T has a yield strength of 900 MPa (131 ksi) and a tensile strength of 1,300 MPa (189 ksi) — stronger than 90% of steel grades. Elongation at break is 8% and the elastic modulus is 205 GPa (29.7 Msi). 1090 Q&T has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,370°C (2,498 °F). HR is the default condition FabDigit quotes; Q&T is available on request or by drawing note.
Advantages
- Polishes to a fine finish — 75/100, better than 94% of steel grades
- High strength — 900 MPa (131 ksi), better than 90% of steel grades
Limitations
- Difficult to weld — 8/100, worse than 100% of steel grades
- Limited formability — 8/100, worse than 97% of steel grades
- Limited ductility — 8%, worse than 95% of steel grades
- Difficult to machine — 38/100, worse than 80% of steel grades
- Limited service temperature — 300°C (572 °F), worse than 77% of steel grades
1090 Q&T properties
Typical room-temperature values for 1090 Q&T — 14 properties are specific to this condition; the rest are grade-level values shared by every 1090 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
1090 Q&T has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,370°C (2,498 °F).
Mechanical13
1090 Q&T has a yield strength of 900 MPa (131 ksi) and a tensile strength of 1,300 MPa (189 ksi) — stronger than 90% of steel grades. Elongation at break is 8% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
1090 Q&T is rated for continuous service to 300°C (572 °F). It conducts heat at 47 W/m·K (27.2 BTU/hr·ft·°F), better than 75% of steel grades. Thermal expansion is 11.3 µm/m·K (6.28 µin/in·°F).
Electrical3
1090 Q&T conducts electricity at 9 % IACS, better than 70% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 87% of steel grades.
Sustainability4
Producing a kilogram of 1090 Q&T takes about 26 MJ of energy and emits 2 kg of CO₂ — less than 64% of steel grades. Typical recycled content is 28%.
Manufacturability7
1090 Q&T's machinability is fair (38/100, worse than 80% of steel grades); weldability not recommended (8/100); formability not recommended (8/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 1090 tempers and conditions
1090 is also supplied in 7 other conditions. The full side-by-side table is on the 1090 overview.
- HRDefaultDefault stock condition for bar, plate and coil; machine or heat-treat afterwards.580 MPa yield · 285 HB
- Q&T 55-60 HRCMaximum hardness/edge retention for blades, saws and wear strips; brittle, avoid shock and notches.1,650 MPa yield · 58 HRC
- Q&T 45-50 HRCWear-resistant spring/blade temper balancing hardness with acceptable fatigue strength.1,200 MPa yield · 48 HRC
- Q&TGeneral hardened-and-tempered condition for springs and high-strength wear parts needing some toughness.900 MPa yield · 42 HRC
- CRPick for strip, close-tolerance bar and better surface where extra strength and low ductility are acceptable.830 MPa yield · 302 HB
- Spheroidized-CDSpheroidize-annealed to globular carbides for cold workability, then cold drawn — moderate strength with better ductility and machinability than pearlitic cold-drawn 1090.620 MPa yield · 217 HB
- NormalizedUse to refine and homogenise the as-rolled structure before hardening or machining of larger sections.500 MPa yield · 293 HB
- AnnealedChoose for maximum machinability and cold formability before hardening.380 MPa yield · 192 HB
Working with 1090 Q&T
Is 1090 easy to machine?
Machine in the annealed/spheroidized state with rigid setups, low speeds and carbide or coated carbide; hardened 1090 needs grinding or ceramic/CBN turning.
Can 1090 be welded?
Essentially not recommended — preheat 250–300 °C, low-hydrogen filler and immediate post-weld temper are mandatory to avoid quench cracking.
Can 1090 be formed, bent or molded?
Cold form only when annealed and with generous radii; otherwise hot work 850–1100 °C and slow cool, then normalize before hardening.
What surface finishes work on 1090?
No anodizing; protect with oil, phosphate, black oxide, paint or zinc/Ni plating (bake after plating to avoid hydrogen embrittlement of hardened parts).
1090 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 |
|---|---|---|
| CGB 90 steel: 0.85–0.95 | 0.85 – 0.98 | 0.91 |
| MnGB 90 steel uses 0.50–0.80 | 0.6 – 0.9 | 0.75 |
| Sitypical for killed product; not specified in AISI 10xx bar chemistry | 0.15 – 0.35 | 0.25 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.05 | 0.03 |
| Fe | balance | — |
1090 Q&T — frequently asked
What is 1090 Q&T used for?
1090 Q&T is typically used for music wire, springs and knife blanks. In short: high-carbon spring sheet.
What is the yield strength of 1090 Q&T?
1090 Q&T has a typical yield strength of 900 MPa (131 ksi) and a tensile strength of 1,300 MPa (189 ksi) — stronger than 90% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is 1090 Q&T easy to machine?
Not especially — machinability is rated fair (38/100, worse than 80% of steel grades). Machine in the annealed/spheroidized state with rigid setups, low speeds and carbide or coated carbide; hardened 1090 needs grinding or ceramic/CBN turning.
Can 1090 Q&T be welded?
Not readily — weldability is rated not recommended (8/100). Essentially not recommended — preheat 250–300 °C, low-hydrogen filler and immediate post-weld temper are mandatory to avoid quench cracking.
What surface finishes work on 1090 Q&T?
No anodizing; protect with oil, phosphate, black oxide, paint or zinc/Ni plating (bake after plating to avoid hydrogen embrittlement of hardened parts).
Can 1090 Q&T be formed, bent or molded?
Cold form only when annealed and with generous radii; otherwise hot work 850–1100 °C and slow cool, then normalize before hardening.
What is the maximum service temperature of 1090 Q&T?
1090 Q&T is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1090-HR and 1090-CR?
HR is the default condition — default stock condition for bar, plate and coil; machine or heat-treat afterwards. CR: pick for strip, close-tolerance bar and better surface where extra strength and low ductility are acceptable. Yield strength is 580 MPa in HR versus 830 MPa in CR.
Can FabDigit make parts in 1090 Q&T?
Yes — 1090 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
- ASTM A29/A29M — Steel Bars, Carbon and Alloy, Hot-Wrought, General Requirements — ASTM (2020)
- SAE J403 — Chemical Compositions of SAE Carbon Steels — SAE International (2014)
- GB/T 699 — Quality Carbon Structural Steels — SAC (2015)
- 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.4 — Heat Treating — ASM International (1991)
- Mysteel / SMM (2026)
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.