Steel P460QL1 QT+SR
Heat-treated state
EN 1.8872
Choose when the vessel receives post-weld heat treatment; properties are certified after a simulated PWHT cycle (typically 530–580 °C), with a small strength debit.
Values for the QT+SR condition
Other P460QL1 tempers and conditions
P460QL1 is listed in 4 conditions; see the grade overview at P460QL1.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
QT | Thickest EN 10028-6 range; reduced strength level, used for heavy nozzle and shell forgings/plates. | 440 | 580 | 21 | 12 HRC | 7.2 % IACS |
QT | Heavy plate section where the standard drops the guaranteed yield to 440 MPa due to lower quench severity. | 480 | 610 | 22 | 15 HRC | 7.2 % IACS |
QT+SRThis page quenched, tempered and stress relieved / simulated PWHT | Choose when the vessel receives post-weld heat treatment; properties are certified after a simulated PWHT cycle (typically 530–580 °C), with a small strength debit. | 480 | 600 | 23 | 15 HRC | 7.2 % IACS |
QTDefault Quenched and tempered | Standard EN 10028-6 delivery condition for plate up to 50 mm; full 460 MPa minimum yield with −40 °C impact guarantee. | 500 | 630 | 22 | 18 HRC | 7.2 % IACS |
What is P460QL1 QT+SR?
P460QL1 QT+SR is P460QL1 heat treated to QT+SR — choose when the vessel receives post-weld heat treatment; properties are certified after a simulated PWHT cycle (typically 530–580 °C), with a small strength debit. P460QL1 QT+SR has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 600 MPa (87 ksi) — stronger than 59% of steel grades. Elongation at break is 23% and the elastic modulus is 210 GPa (30.5 Msi). P460QL1 QT+SR 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). QT is the default condition FabDigit quotes; QT+SR is available on request or by drawing note.
Advantages
- Tough — resists crack growth — 160 MPa·√m (145.6 ksi·√in), better than 98% of steel grades
Limitations
- Hard to polish — 45/100, worse than 84% of steel grades
P460QL1 QT+SR properties
Typical room-temperature values for P460QL1 QT+SR; 24 are specific to this condition. Other listed values are P460QL1 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
P460QL1 QT+SR 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).
Mechanical17
P460QL1 QT+SR has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 600 MPa (87 ksi) — stronger than 59% of steel grades. Elongation at break is 23% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
P460QL1 QT+SR is rated for continuous service to 400°C (752 °F). It conducts heat at 40 W/m·K (23.1 BTU/hr·ft·°F), worse than 64% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
P460QL1 QT+SR conducts electricity at 7.2 % IACS, worse than 71% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of P460QL1 QT+SR takes about 26 MJ of energy and emits 2.1 kg of CO₂ — less than 64% of steel grades. Typical recycled content is 20%.
Manufacturability7
P460QL1 QT+SR's machinability is fair (53/100, better than 53% of steel grades); weldability very good (70/100); formability fair (48/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with P460QL1 QT+SR
Is P460QL1 easy to machine?
Machines like a 200 HB quenched-and-tempered low-alloy steel — rigid setup, coated carbide, moderate speeds; expect ~55 % of AISI 1212 and residual-stress movement when taking deep cuts from heavy plate.
Can P460QL1 be welded?
Readily weldable with low-hydrogen SMAW/SAW/FCAW consumables matching 460 MPa; control CEV, use ≥100–150 °C preheat on heavy sections, limit heat input and interpass (~250 °C) to protect −40 °C HAZ toughness, and keep any PWHT below the tempering temperature.
Can P460QL1 be formed, bent or molded?
Cold forming is possible but requires generous bend radii (≥3t transverse) because of the high yield/tensile ratio; hot forming above ~580 °C destroys the Q&T condition and requires re-quenching and tempering.
What surface finishes work on P460QL1?
No natural corrosion resistance — shot-blast to Sa 2½ and apply epoxy/zinc-rich paint, metallizing or weld overlay; anodizing is not applicable.
P460QL1 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 10028-6 | ≤ 0.2 | 0.16 |
| Si | ≤ 0.6 | 0.3 |
| Mn | 1 – 1.7 | 1.4 |
| Ptightened for QL1 low-temperature grade | ≤ 0.02 | 0.01 |
| Slow S for through-thickness toughness | ≤ 0.01 | 0 |
| N | ≤ 0.02 | 0.01 |
| Altotal Al, grain refinement | ≥ 0.02 | 0.03 |
| Cr | ≤ 0.5 | 0.25 |
| Cu | ≤ 0.5 | 0.15 |
| Mo | ≤ 0.7 | 0.35 |
| Nikey element for −40 °C toughness | ≤ 1.5 | 0.6 |
| Nb | ≤ 0.05 | 0.03 |
| Ti | ≤ 0.05 | 0.02 |
| V | ≤ 0.12 | 0.05 |
| Zr | ≤ 0.05 | — |
| Bhardenability booster, optional | ≤ 0.01 | 0 |
| Fe | balance | — |
P460QL1 QT+SR — frequently asked
What is P460QL1 QT+SR used for?
P460QL1 QT+SR is typically used for cryogenic pressure vessels, LNG storage tanks, low-temperature process equipment and offshore Arctic structures. In short: sub-zero toughness plate; weldable 460 MPa vessel steel; high yield-to-tensile ratio.
What is the yield strength of P460QL1 QT+SR?
P460QL1 QT+SR has a typical yield strength of 480 MPa (69.6 ksi) and a tensile strength of 600 MPa (87 ksi) — stronger than 59% of steel grades. Strength varies by condition: see the 4 listed tempers.
Is P460QL1 QT+SR easy to machine?
Reasonably — machinability is rated fair (53/100, better than 53% of steel grades). Machines like a 200 HB quenched-and-tempered low-alloy steel — rigid setup, coated carbide, moderate speeds; expect ~55 % of AISI 1212 and residual-stress movement when taking deep cuts from heavy plate.
Can P460QL1 QT+SR be welded?
Yes — weldability is rated very good (70/100). Readily weldable with low-hydrogen SMAW/SAW/FCAW consumables matching 460 MPa; control CEV, use ≥100–150 °C preheat on heavy sections, limit heat input and interpass (~250 °C) to protect −40 °C HAZ toughness, and keep any PWHT below the tempering temperature.
What surface finishes work on P460QL1 QT+SR?
No natural corrosion resistance — shot-blast to Sa 2½ and apply epoxy/zinc-rich paint, metallizing or weld overlay; anodizing is not applicable.
Can P460QL1 QT+SR be formed, bent or molded?
Cold forming is possible but requires generous bend radii (≥3t transverse) because of the high yield/tensile ratio; hot forming above ~580 °C destroys the Q&T condition and requires re-quenching and tempering.
What is the maximum service temperature of P460QL1 QT+SR?
P460QL1 QT+SR 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.
Sources
- EN 10028-6 Flat products made of steels for pressure purposes — Part 6: Weldable fine grain steels, quenched and tempered — CEN (2020)
- EN 10027-2 Designation systems for steels — Steel numbers (1.8872) — CEN (2015)
- EN 1011-2 Welding — Recommendations for welding of metallic materials: Arc welding of ferritic steels — CEN (2001)
- ASM Handbook Vol.1: Properties and Selection — Irons, Steels and High-Performance Alloys — ASM International (1990)
- Quenched and tempered pressure vessel plate P355Q–P460QL2 datasheets — Dillinger / voestalpine Grobblech (2022)
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.