Steel P500QL2-QT (Quenched and tempered)
Heat-treated state · default condition
EN 1.8865, 10028-6
Standard delivery condition for plate up to 50 mm — full 500 MPa minimum yield with −60 °C toughness.
Values for the QT condition
Other P500QL2 tempers and conditions
P500QL2 is listed in 4 conditions; see the grade overview at P500QL2.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Q+T | Maximum thickness range offered; use when wall thickness governs and the reduced yield is acceptable. | 480 | 610 | 20 | 13 HRC | 7.2 % IACS |
Q+T | Heavy plate condition; slightly lower guaranteed yield due to reduced quench severity through thickness. | 520 | 640 | 21 | 16 HRC | 7.2 % IACS |
Q+T + stress relieved / simulated PWHT | Order this when the fabricated vessel will see PWHT — properties are certified after a simulated post-weld heat treatment cycle below the tempering temperature. | 520 | 630 | 22 | 15 HRC | 7.2 % IACS |
QTDefaultThis page Quenched and tempered | Standard delivery condition for plate up to 50 mm — full 500 MPa minimum yield with −60 °C toughness. | 545 | 660 | 21 | 19 HRC | 7.2 % IACS |
What is P500QL2-QT?
P500QL2-QT is P500QL2 heat treated to QT — standard delivery condition for plate up to 50 mm — full 500 MPa minimum yield with −60 °C toughness. P500QL2-QT has a yield strength of 545 MPa (79 ksi) and a tensile strength of 660 MPa (95.7 ksi) — stronger than 70% of steel grades. Elongation at break is 21% and the elastic modulus is 210 GPa (30.5 Msi). P500QL2-QT has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F).
Advantages
- Tough — resists crack growth — 130 MPa·√m (118.3 ksi·√in), better than 89% of steel grades
P500QL2-QT properties
Typical room-temperature values for P500QL2-QT; 24 are specific to this condition. Other listed values are P500QL2 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
P500QL2-QT has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical17
P500QL2-QT has a yield strength of 545 MPa (79 ksi) and a tensile strength of 660 MPa (95.7 ksi) — stronger than 70% of steel grades. Elongation at break is 21% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
P500QL2-QT is rated for continuous service to 400°C (752 °F). It conducts heat at 38 W/m·K (22 BTU/hr·ft·°F), worse than 69% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
P500QL2-QT conducts electricity at 7.2 % IACS, worse than 71% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (15/100), better than 75% of steel grades.
Sustainability4
Producing a kilogram of P500QL2-QT takes about 30 MJ of energy and emits 2.3 kg of CO₂ — more than 56% of steel grades. Typical recycled content is 20%.
Manufacturability7
P500QL2-QT's machinability is fair (45/100, worse than 65% of steel grades); weldability good (60/100); formability fair (40/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with P500QL2-QT
Is P500QL2 easy to machine?
Machines like a 215 HB Q&T alloy steel — use rigid setups, coated carbide, moderate speeds; avoid heavy grinding that could re-temper or crack the surface.
Can P500QL2 be welded?
Weldable by SAW/FCAW/SMAW with low-hydrogen consumables; preheat 100–150 °C (higher for t>50 mm), control interpass ≤250 °C and heat input to protect the −60 °C HAZ toughness, and keep PWHT below the tempering temperature.
Can P500QL2 be formed, bent or molded?
Cold form with bend radii ≥3t across the rolling direction; hot forming above ~580 °C destroys the Q&T condition and requires full re-quench and temper.
What surface finishes work on P500QL2?
No inherent corrosion resistance — blast to Sa 2½ and apply epoxy/zinc-rich paint or metallizing; keep surface hardness ≤248 HV for wet H2S service.
P500QL2 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 | ≤ 0.18 | 0.15 |
| Si | ≤ 0.6 | 0.3 |
| Mn | 0.8 – 1.7 | 1.3 |
| PQL2 grade, low P for toughness | ≤ 0.02 | 0.01 |
| SQL2 grade, calcium-treated | ≤ 0.01 | 0 |
| N | ≤ 0.02 | 0.01 |
| Altotal Al, grain refinement | ≥ 0.02 | 0.04 |
| Cr | ≤ 1.5 | 0.5 |
| Cu | ≤ 0.5 | 0.15 |
| Mo | ≤ 0.7 | 0.45 |
| Nimain contributor to low-temperature toughness | ≤ 2.5 | 1.2 |
| Nb | ≤ 0.06 | 0.03 |
| Ti | ≤ 0.05 | 0.02 |
| V | ≤ 0.12 | 0.05 |
| Zr | ≤ 0.05 | — |
| Bhardenability booster | ≤ 0.01 | 0 |
| Fe | balance | — |
P500QL2-QT — frequently asked
What is P500QL2-QT used for?
P500QL2-QT is typically used for high-pressure cryogenic vessels, LNG tanks and chemical reactors. In short: 500 MPa Q&T vessel plate; L2 toughness at high strength; step above P460QL2.
What is the yield strength of P500QL2-QT?
P500QL2-QT has a typical yield strength of 545 MPa (79 ksi) and a tensile strength of 660 MPa (95.7 ksi) — stronger than 70% of steel grades. Strength varies by condition: see the 4 listed tempers.
Is P500QL2-QT easy to machine?
Reasonably — machinability is rated fair (45/100, worse than 65% of steel grades). Machines like a 215 HB Q&T alloy steel — use rigid setups, coated carbide, moderate speeds; avoid heavy grinding that could re-temper or crack the surface.
Can P500QL2-QT be welded?
Yes — weldability is rated good (60/100). Weldable by SAW/FCAW/SMAW with low-hydrogen consumables; preheat 100–150 °C (higher for t>50 mm), control interpass ≤250 °C and heat input to protect the −60 °C HAZ toughness, and keep PWHT below the tempering temperature.
What surface finishes work on P500QL2-QT?
No inherent corrosion resistance — blast to Sa 2½ and apply epoxy/zinc-rich paint or metallizing; keep surface hardness ≤248 HV for wet H2S service.
Can P500QL2-QT be formed, bent or molded?
Cold form with bend radii ≥3t across the rolling direction; hot forming above ~580 °C destroys the Q&T condition and requires full re-quench and temper.
What is the maximum service temperature of P500QL2-QT?
P500QL2-QT 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 10025-6 / EN 10029 (tolerances, related Q&T plate practice) — CEN (2019)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- Quenched and tempered pressure vessel plate datasheets (Dillinger, SSAB, thyssenkrupp) — various producers (2023)
- NACE MR0175 / ISO 15156-2 hardness limits for wet H2S service — ISO/NACE (2020)
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.