Steel 15MnMoV4-5 +QT (Quenched and tempered)
Heat-treated state
EN 15MnMoV4-5
Pick for heavy sections or forgings needing the highest yield strength and through-thickness toughness.
Values for the +QT condition
Other 15MnMoV4-5 tempers and conditions
15MnMoV4-5 is listed in 6 conditions; see the grade overview at 15MnMoV4-5.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Pick for maximum machinability and cold formability before final heat treatment. | 330 | 540 | 26 | 160 HB | 7.8 % IACS |
Hot rolled | Lowest-cost supply for parts that will be re-heat-treated after forming or machining. | 420 | 620 | 20 | 190 HB | 7.5 % IACS |
Normalized | Pick for uniform fine-grained plate/forging with good toughness where the highest strength is not required. | 430 | 610 | 22 | 185 HB | — |
Stress relieved | Order when the vessel will see a long post-weld heat treatment and design values must reflect the softened condition. | 440 | 610 | 21 | 185 HB | 7.5 % IACS |
+NTDefault Normalized and tempered | Standard stocked condition for pressure-vessel plate: balanced strength, toughness and elevated-temperature stability. | 460 | 640 | 20 | 195 HB | — |
+QTThis page Quenched and tempered | Pick for heavy sections or forgings needing the highest yield strength and through-thickness toughness. | 550 | 720 | 18 | 21 HRC | — |
What is 15MnMoV4-5 +QT?
15MnMoV4-5 +QT is 15MnMoV4-5 heat treated to +QT — pick for heavy sections or forgings needing the highest yield strength and through-thickness toughness. 15MnMoV4-5 +QT has a yield strength of 550 MPa (79.8 ksi) and a tensile strength of 720 MPa (104 ksi) — stronger than 71% of steel grades. Elongation at break is 18% and the elastic modulus is 210 GPa (30.5 Msi). 15MnMoV4-5 +QT 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). +NT is the default condition FabDigit quotes; +QT is available on request or by drawing note.
Advantages
- High service temperature — 480°C (896 °F), better than 88% of steel grades
- Tough — resists crack growth — 120 MPa·√m (109.2 ksi·√in), better than 81% of steel grades
15MnMoV4-5 +QT properties
Typical room-temperature values for 15MnMoV4-5 +QT; 12 are specific to this condition. Other listed values are 15MnMoV4-5 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
15MnMoV4-5 +QT 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
15MnMoV4-5 +QT has a yield strength of 550 MPa (79.8 ksi) and a tensile strength of 720 MPa (104 ksi) — stronger than 71% of steel grades. Elongation at break is 18% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
15MnMoV4-5 +QT is rated for continuous service to 480°C (896 °F). It conducts heat at 40 W/m·K (23.1 BTU/hr·ft·°F), worse than 64% of steel grades. Thermal expansion is 12.3 µm/m·K (6.83 µin/in·°F).
Electrical3
15MnMoV4-5 +QT conducts electricity at 7.5 % IACS, worse than 67% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of 15MnMoV4-5 +QT takes about 31 MJ of energy and emits 2.2 kg of CO₂ — more than 64% of steel grades. Typical recycled content is 25%.
Manufacturability7
15MnMoV4-5 +QT's machinability is good (55/100, better than 62% of steel grades); weldability fair (50/100); formability fair (50/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 15MnMoV4-5 +QT
Is 15MnMoV4-5 easy to machine?
Machines like a 500–650 MPa alloy steel: rigid setups, coated carbide, 80–140 m/min turning; vanadium carbides accelerate edge wear so keep feeds up and avoid dwelling.
Can 15MnMoV4-5 be welded?
Weldable by SMAW/SAW/GTAW with matching Mn-Mo(-V) or 1.25Cr-0.5Mo consumables; preheat ~150–250 °C depending on thickness, low-hydrogen practice, and 600–680 °C PWHT to restore toughness and avoid reheat cracking.
Can 15MnMoV4-5 be formed, bent or molded?
Hot form at 950–1150 °C followed by re-normalizing/tempering; cold bending is possible in the annealed or +NT state with generous bend radii (≥3t) and no flame straightening.
What surface finishes work on 15MnMoV4-5?
No inherent corrosion resistance — shot blast then epoxy/zinc-rich primer, aluminizing or weld-overlay cladding; electroplating requires post-bake to avoid hydrogen embrittlement in Q&T condition.
15MnMoV4-5 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 |
|---|---|---|
| Cdesignation digit 15 = 0.15 % C | 0.12 – 0.18 | 0.15 |
| Si | 0.15 – 0.4 | 0.3 |
| Mndesignation 4/4 = 1.0 % Mn | 0.85 – 1.2 | 1 |
| P | ≤ 0.03 | — |
| S | ≤ 0.02 | — |
| Modesignation 5/10 = 0.5 % Mo | 0.4 – 0.55 | 0.5 |
| Vmicroalloy precipitation strengthener | 0.06 – 0.12 | 0.09 |
| Crresidual | ≤ 0.3 | — |
| Niresidual | ≤ 0.3 | — |
| Curesidual | ≤ 0.3 | — |
| Algrain refining, total Al | 0.02 – 0.06 | 0.03 |
| Fe | balance | — |
15MnMoV4-5 +QT — frequently asked
What is 15MnMoV4-5 +QT used for?
15MnMoV4-5 +QT is typically used for pressure vessels, boiler components and piping. In short: elevated-temperature pressure steel; weldable with 600-680 °C PWHT; 480 °C service limit.
What is the yield strength of 15MnMoV4-5 +QT?
15MnMoV4-5 +QT has a typical yield strength of 550 MPa (79.8 ksi) and a tensile strength of 720 MPa (104 ksi) — stronger than 71% of steel grades. Strength varies by condition: see the 6 listed tempers.
Is 15MnMoV4-5 +QT easy to machine?
Reasonably — machinability is rated good (55/100, better than 62% of steel grades). Machines like a 500–650 MPa alloy steel: rigid setups, coated carbide, 80–140 m/min turning; vanadium carbides accelerate edge wear so keep feeds up and avoid dwelling.
Can 15MnMoV4-5 +QT be welded?
With care — weldability is rated fair (50/100). Weldable by SMAW/SAW/GTAW with matching Mn-Mo(-V) or 1.25Cr-0.5Mo consumables; preheat ~150–250 °C depending on thickness, low-hydrogen practice, and 600–680 °C PWHT to restore toughness and avoid reheat cracking.
What surface finishes work on 15MnMoV4-5 +QT?
No inherent corrosion resistance — shot blast then epoxy/zinc-rich primer, aluminizing or weld-overlay cladding; electroplating requires post-bake to avoid hydrogen embrittlement in Q&T condition.
Can 15MnMoV4-5 +QT be formed, bent or molded?
Hot form at 950–1150 °C followed by re-normalizing/tempering; cold bending is possible in the annealed or +NT state with generous bend radii (≥3t) and no flame straightening.
What is the maximum service temperature of 15MnMoV4-5 +QT?
15MnMoV4-5 +QT is rated for continuous use to about 480°C (896 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- EN 10028-2 Flat products made of steels for pressure purposes — Non-alloy and alloy steels with specified elevated temperature properties — CEN (2017)
- EN 10027-1/10027-2 Designation systems for steels (name and material number 1.5402) — CEN (2016)
- EN 10083-3 Steels for quenching and tempering — Alloy steels — CEN (2006)
- 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)
- EN 1011-2 Welding — Recommendations for welding of metallic materials: Arc welding of ferritic steels — CEN (2001)
- 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.