Steel S960QL Q&T+SR
Heat-treated state
EN S960QL
Q&T+SR = q&T + stress relieved
Use after heavy welding or machining of thick fabrications where distortion control matters; accept a modest drop in strength.
Values for the Q&T+SR condition
Other S960QL tempers and conditions
S960QL is listed in 3 conditions; see the grade overview at S960QL.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
heavy plate, t > 50 mm (producer-extended thickness) | Choose for heavy sections beyond the EN table range, where producers supply reduced guaranteed yield due to lower quench severity. | 940 | 1,000 | 13 | 32 HRC | 7 % IACS |
Q&T+SRThis page Q&T + stress relieved | Use after heavy welding or machining of thick fabrications where distortion control matters; accept a modest drop in strength. | 950 | 1,010 | 13 | 33 HRC | 7 % IACS |
Q&TDefault Quenched and tempered | Standard as-delivered condition of S960QL plate; pick this for all normal structural use up to 50 mm thickness. | 1,010 | 1,050 | 12 | 34 HRC | — |
What is S960QL Q&T+SR?
S960QL Q&T+SR is S960QL heat treated to Q&T+SR — use after heavy welding or machining of thick fabrications where distortion control matters; accept a modest drop in strength. S960QL Q&T+SR has a yield strength of 950 MPa (138 ksi) and a tensile strength of 1,010 MPa (146 ksi) — stronger than 91% of steel grades. Elongation at break is 13% and the elastic modulus is 210 GPa (30.5 Msi). S960QL Q&T+SR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,460°C (2,660 °F). Q&T is the default condition FabDigit quotes; Q&T+SR is available on request or by drawing note.
Advantages
- High strength — 950 MPa (138 ksi), better than 91% of steel grades
Limitations
- Difficult to machine — 36/100, worse than 81% of steel grades
- Limited ductility — 13%, worse than 78% of steel grades
- Poor heat conductor — 34 W/m·K (19.6 BTU/hr·ft·°F), worse than 77% of steel grades
S960QL Q&T+SR properties
Typical room-temperature values for S960QL Q&T+SR; 22 are specific to this condition. Other listed values are S960QL reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
S960QL Q&T+SR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,460°C (2,660 °F).
Mechanical16
S960QL Q&T+SR has a yield strength of 950 MPa (138 ksi) and a tensile strength of 1,010 MPa (146 ksi) — stronger than 91% of steel grades. Elongation at break is 13% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
S960QL Q&T+SR is rated for continuous service to 350°C (662 °F). It conducts heat at 34 W/m·K (19.6 BTU/hr·ft·°F), worse than 77% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
S960QL Q&T+SR conducts electricity at 7 % IACS, worse than 74% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of S960QL Q&T+SR takes about 30 MJ of energy and emits 2.3 kg of CO₂ — more than 56% of steel grades. Typical recycled content is 25%.
Manufacturability8
S960QL Q&T+SR's machinability is fair (36/100, worse than 81% of steel grades); weldability good (58/100); formability fair (42/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with S960QL Q&T+SR
Is S960QL easy to machine?
Machines like a ~320 HB Q&T low-alloy steel — rigid setups, coated carbide, moderate speed and heavy positive feed to stay below the work-hardened skin.
Can S960QL be welded?
Weldable with low-hydrogen (H5) matching or slightly under-matching consumables; preheat typically 100–150 °C depending on thickness and CEV, interpass ≤ 200 °C and heat input controlled (~1.0–1.7 kJ/mm) to limit HAZ softening.
Can S960QL be formed, bent or molded?
Cold bendable but only with generous radii (≈3–4×t transverse to rolling direction), large springback and de-burred, crack-free flame-cut edges; hot forming above the tempering temperature destroys the Q&T properties.
What surface finishes work on S960QL?
No natural corrosion resistance — blast to Sa 2.5 and apply zinc-rich primer/epoxy paint or metallize; avoid electroplating without baking due to hydrogen embrittlement risk.
S960QL 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 |
|---|---|---|
| Cladle analysis max per EN 10025-6 | ≤ 0.2 | 0.17 |
| Si | ≤ 0.5 | 0.3 |
| Mn | ≤ 1.7 | 1.3 |
| P | ≤ 0.02 | 0.01 |
| S | ≤ 0.01 | 0 |
| N | ≤ 0.02 | 0.01 |
| B | ≤ 0.01 | 0 |
| Cr | ≤ 1.5 | 0.6 |
| Cu | ≤ 0.5 | 0.15 |
| Mo | ≤ 0.7 | 0.5 |
| Nb | ≤ 0.06 | 0.02 |
| Ni | ≤ 2 | 1.2 |
| Ti | ≤ 0.05 | 0.02 |
| V | ≤ 0.12 | 0.05 |
| Zr | ≤ 0.15 | — |
| Fe | balance | — |
S960QL Q&T+SR — frequently asked
What is S960QL Q&T+SR used for?
S960QL Q&T+SR is typically used for mobile crane booms, concrete pump booms, truck-mounted crane jibs, excavator booms and arms, mining equipment structures and heavy-haul trailer chassis. In short: workhorse high-strength plate.
What is the yield strength of S960QL Q&T+SR?
S960QL Q&T+SR has a typical yield strength of 950 MPa (138 ksi) and a tensile strength of 1,010 MPa (146 ksi) — stronger than 91% of steel grades. Strength varies by condition: see the 3 listed tempers.
Is S960QL Q&T+SR easy to machine?
Not especially — machinability is rated fair (36/100, worse than 81% of steel grades). Machines like a ~320 HB Q&T low-alloy steel — rigid setups, coated carbide, moderate speed and heavy positive feed to stay below the work-hardened skin.
Can S960QL Q&T+SR be welded?
Yes — weldability is rated good (58/100). Weldable with low-hydrogen (H5) matching or slightly under-matching consumables; preheat typically 100–150 °C depending on thickness and CEV, interpass ≤ 200 °C and heat input controlled (~1.0–1.7 kJ/mm) to limit HAZ softening.
What surface finishes work on S960QL Q&T+SR?
No natural corrosion resistance — blast to Sa 2.5 and apply zinc-rich primer/epoxy paint or metallize; avoid electroplating without baking due to hydrogen embrittlement risk.
Can S960QL Q&T+SR be formed, bent or molded?
Cold bendable but only with generous radii (≈3–4×t transverse to rolling direction), large springback and de-burred, crack-free flame-cut edges; hot forming above the tempering temperature destroys the Q&T properties.
What is the maximum service temperature of S960QL Q&T+SR?
S960QL Q&T+SR 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.
Can FabDigit make parts in S960QL Q&T+SR?
Yes — S960QL Q&T+SR is available for CNC machining and sheet metal; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- EN 10025-6 Hot rolled products of structural steels — Part 6: flat products of high yield strength structural steels in the quenched and tempered condition — CEN (2019)
- Strenx 960 / Weldox 960 structural steel plate data — SSAB (2023)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
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.