Steel P460QH QT+SR
Heat-treated state
EN P460QH
QT+SR = q+T + stress relieved / simulated PWHT
Order this when the vessel or hollow section will see post-weld heat treatment — properties verified after simulated PWHT (below tempering temperature).
Values for the QT+SR condition
Other P460QH tempers and conditions
P460QH is listed in 4 conditions; see the grade overview at P460QH.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Q+T | Very heavy sections and forgings; lowest guaranteed strength band of the grade. | 430 | 570 | 20 | 9 HRC | 7.8 % IACS |
Q+T | Heavy plate / thick-wall sections; specified strength drops one step due to lower quench severity. | 470 | 590 | 21 | 11 HRC | 7.8 % IACS |
QT+SRThis page Q+T + stress relieved / simulated PWHT | Order this when the vessel or hollow section will see post-weld heat treatment — properties verified after simulated PWHT (below tempering temperature). | 480 | 605 | 22 | 195 HB | 7.8 % IACS |
QTDefault Quenched and tempered | Standard supply condition for plate, tube and forgings up to 50 mm — full 460 MPa yield class. | 500 | 620 | 21 | 14 HRC | 7.8 % IACS |
What is P460QH QT+SR?
P460QH QT+SR is P460QH heat treated to QT+SR — order this when the vessel or hollow section will see post-weld heat treatment — properties verified after simulated PWHT (below tempering temperature). P460QH QT+SR has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 605 MPa (87.7 ksi) — stronger than 59% of steel grades. Elongation at break is 22% and the elastic modulus is 210 GPa (30.5 Msi). P460QH 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 — 125 MPa·√m (113.8 ksi·√in), better than 85% of steel grades
- Readily welded — 74/100, better than 76% of steel grades
P460QH QT+SR properties
Typical room-temperature values for P460QH QT+SR; 22 are specific to this condition. Other listed values are P460QH reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
P460QH 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
P460QH QT+SR has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 605 MPa (87.7 ksi) — stronger than 59% of steel grades. Elongation at break is 22% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
P460QH 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
P460QH QT+SR conducts electricity at 7.8 % IACS, worse than 57% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of P460QH QT+SR takes about 30 MJ of energy and emits 2.2 kg of CO₂ — more than 56% of steel grades. Typical recycled content is 25%.
Manufacturability7
P460QH QT+SR's machinability is good (57/100, better than 71% of steel grades); weldability very good (74/100); formability fair (47/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with P460QH QT+SR
Is P460QH easy to machine?
Machines like 4130/4140 at ~200 HB: rigid setups, coated carbide, moderate speeds and generous feed; avoid rubbing that work-hardens the surface.
Can P460QH be welded?
Good weldability with low-hydrogen consumables; CEV ≈0.45–0.50 so preheat 100–150 °C in thick sections, control heat input and keep any PWHT at least 30 °C below the tempering temperature.
Can P460QH be formed, bent or molded?
Cold form with generous bend radii (≥3t for thin, ≥4–5t heavy) transverse to rolling direction; hot forming above the tempering temperature destroys the Q+T properties and requires re-quenching and tempering.
What surface finishes work on P460QH?
Blast and paint, metallize or hot-dip galvanize (check silicon level); no anodizing — phosphate or zinc-rich primer for atmospheric service.
P460QH 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 | ≤ 0.2 | 0.16 |
| Si | ≤ 0.6 | 0.35 |
| Mn | 1 – 1.7 | 1.4 |
| P | ≤ 0.03 | 0.01 |
| S | ≤ 0.02 | 0.01 |
| Cr | ≤ 1.5 | 0.3 |
| NiNi raises hardenability and low-temperature toughness | ≤ 2 | 0.6 |
| Mo | ≤ 0.7 | 0.25 |
| Cu | ≤ 0.5 | 0.15 |
| V | ≤ 0.12 | 0.05 |
| Nb | ≤ 0.06 | 0.03 |
| Ti | ≤ 0.05 | 0.02 |
| Zr | ≤ 0.05 | — |
| B | ≤ 0.01 | — |
| N | ≤ 0.03 | 0.01 |
| Altotal Al, for fine-grain practice | ≥ 0.02 | 0.03 |
| Fe | balance | — |
P460QH QT+SR — frequently asked
What is P460QH QT+SR used for?
P460QH QT+SR is typically used for structural hollow sections, pressure vessel nozzles, offshore tubular structures and heavy machinery frames. In short: Q+T strength in tube; weldable 460 MPa grade; needs coating for corrosion.
What is the yield strength of P460QH QT+SR?
P460QH QT+SR has a typical yield strength of 480 MPa (69.6 ksi) and a tensile strength of 605 MPa (87.7 ksi) — stronger than 59% of steel grades. Strength varies by condition: see the 4 listed tempers.
Is P460QH QT+SR easy to machine?
Reasonably — machinability is rated good (57/100, better than 71% of steel grades). Machines like 4130/4140 at ~200 HB: rigid setups, coated carbide, moderate speeds and generous feed; avoid rubbing that work-hardens the surface.
Can P460QH QT+SR be welded?
Yes — weldability is rated very good (74/100). Good weldability with low-hydrogen consumables; CEV ≈0.45–0.50 so preheat 100–150 °C in thick sections, control heat input and keep any PWHT at least 30 °C below the tempering temperature.
What surface finishes work on P460QH QT+SR?
Blast and paint, metallize or hot-dip galvanize (check silicon level); no anodizing — phosphate or zinc-rich primer for atmospheric service.
Can P460QH QT+SR be formed, bent or molded?
Cold form with generous bend radii (≥3t for thin, ≥4–5t heavy) transverse to rolling direction; hot forming above the tempering temperature destroys the Q+T properties and requires re-quenching and tempering.
What is the maximum service temperature of P460QH QT+SR?
P460QH 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 of steels for pressure purposes — Weldable fine grain steels, quenched and tempered — CEN (2020)
- EN 10222-4 Steel forgings for pressure purposes — Weldable fine grain steels with high proof strength — CEN (2017)
- EN 10027-2 Numerical designation system (1.8871) — CEN (2015)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol. 19 — Fatigue and Fracture — ASM International (1996)
- Quenched and tempered pressure-vessel steel plate datasheets (P460Q/QH class) — European plate mills (2023)
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.