Steel P285NH-N (Normalized)
Heat-treated state · default condition
EN P285NH
Standard supply condition for pressure vessel shells, heads and forgings requiring 285 MPa minimum yield and 40 J at -20 °C.
Values for the N condition
Other P285NH tempers and conditions
P285NH is listed in 4 conditions; see the grade overview at P285NH.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Normalized plus stress relieved / simulated PWHT | Choose when the vessel will see post-weld heat treatment (typ. 560–620 °C) and the plate must be tested in the simulated PWHT condition; slight softening, better dimensional stability. | 305 | 435 | 27 | 133 HB | 10 % IACS |
normalized weldable fine-grain forging per EN 10222-4 | Flanges, nozzles, tube sheets and heavy forged fittings; property class follows section thickness, with reduced proof stress in heavy sections. | 305 | 440 | 24 | 138 HB | 10 % IACS |
NDefaultThis page Normalized | Standard supply condition for pressure vessel shells, heads and forgings requiring 285 MPa minimum yield and 40 J at -20 °C. | 320 | 450 | 26 | 140 HB | — |
Normalizing rolled plate | Plate rolled so that the final pass leaves a normalized-equivalent structure — same guaranteed properties as +N without a separate furnace cycle, cheaper on heavy plate. | 330 | 455 | 26 | 145 HB | 10 % IACS |
What is P285NH-N?
P285NH-N is P285NH heat treated to N — standard supply condition for pressure vessel shells, heads and forgings requiring 285 MPa minimum yield and 40 J at -20 °C. P285NH-N has a yield strength of 320 MPa (46.4 ksi) and a tensile strength of 450 MPa (65.3 ksi) — weaker than 81% of steel grades. Elongation at break is 26% and the elastic modulus is 210 GPa (30.5 Msi). P285NH-N 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).
Advantages
- Readily welded — 90/100, better than 90% of steel grades
- Tough — resists crack growth — 130 MPa·√m (118.3 ksi·√in), better than 89% of steel grades
- Forms and bends easily — 72/100, better than 88% of steel grades
- Conducts heat well — 50 W/m·K (28.9 BTU/hr·ft·°F), better than 87% of steel grades
- High electrical conductivity — 10 % IACS, better than 83% of steel grades
Limitations
- Hard to polish — 45/100, worse than 84% of steel grades
- Low strength — 320 MPa (46.4 ksi), worse than 81% of steel grades
P285NH-N properties
Typical room-temperature values for P285NH-N; 11 are specific to this condition. Other listed values are P285NH reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
P285NH-N 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
P285NH-N has a yield strength of 320 MPa (46.4 ksi) and a tensile strength of 450 MPa (65.3 ksi) — weaker than 81% of steel grades. Elongation at break is 26% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
P285NH-N is rated for continuous service to 400°C (752 °F). It conducts heat at 50 W/m·K (28.9 BTU/hr·ft·°F), better than 87% of steel grades. Thermal expansion is 12.2 µm/m·K (6.78 µin/in·°F).
Electrical3
P285NH-N conducts electricity at 10 % IACS, better than 83% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (11/100), worse than 73% of steel grades.
Sustainability4
Producing a kilogram of P285NH-N takes about 25 MJ of energy and emits 2.1 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 25%.
Manufacturability7
P285NH-N's machinability is good (60/100, better than 83% of steel grades); weldability excellent (90/100); formability very good (72/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with P285NH-N
Is P285NH easy to machine?
Machines like normalized 1020/1518 C-Mn steel at roughly 60 % of AISI 1212; use sharp positive-rake carbide, moderate speeds and good chip control since the low-carbon structure is gummy.
Can P285NH be welded?
Excellent weldability by SMAW/SAW/GMAW with low-hydrogen consumables matching 285 MPa yield; preheat 100–150 °C for heavy sections and apply PWHT at 560–620 °C where the code requires it.
Can P285NH be formed, bent or molded?
Cold roll and press for shells and heads with generous bend radii (≥2 t); hot forming above ~900 °C should be followed by re-normalizing to restore the fine-grain properties.
What surface finishes work on P285NH?
No anodizing; protect by blasting plus epoxy/alkyd painting, metallizing or hot-dip galvanizing, and add a corrosion allowance for wet service.
P285NH 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 | ≤ 0.4 | 0.3 |
| Mn | 0.9 – 1.5 | 1.2 |
| P | ≤ 0.03 | 0.02 |
| S | ≤ 0.02 | 0.01 |
| Altotal Al, grain refining | ≥ 0.02 | 0.03 |
| N | ≤ 0.02 | 0.01 |
| Cr | ≤ 0.3 | 0.05 |
| Cu | ≤ 0.3 | 0.1 |
| Ni | ≤ 0.5 | 0.1 |
| Mo | ≤ 0.08 | 0.02 |
| Nb | ≤ 0.05 | 0.02 |
| Ti | ≤ 0.03 | 0.01 |
| V | ≤ 0.1 | 0.02 |
| Fe | balance | — |
P285NH-N — frequently asked
What is P285NH-N used for?
P285NH-N is typically used for pressure vessel shells, boiler drums, heat exchanger plate and process equipment. In short: easy-welding vessel plate; normalized fine-grain toughness; available as forged shapes.
What is the yield strength of P285NH-N?
P285NH-N has a typical yield strength of 320 MPa (46.4 ksi) and a tensile strength of 450 MPa (65.3 ksi) — weaker than 81% of steel grades. Strength varies by condition: see the 4 listed tempers.
Is P285NH-N easy to machine?
Reasonably — machinability is rated good (60/100, better than 83% of steel grades). Machines like normalized 1020/1518 C-Mn steel at roughly 60 % of AISI 1212; use sharp positive-rake carbide, moderate speeds and good chip control since the low-carbon structure is gummy.
Can P285NH-N be welded?
Yes — weldability is rated excellent (90/100). Excellent weldability by SMAW/SAW/GMAW with low-hydrogen consumables matching 285 MPa yield; preheat 100–150 °C for heavy sections and apply PWHT at 560–620 °C where the code requires it.
What surface finishes work on P285NH-N?
No anodizing; protect by blasting plus epoxy/alkyd painting, metallizing or hot-dip galvanizing, and add a corrosion allowance for wet service.
Can P285NH-N be formed, bent or molded?
Cold roll and press for shells and heads with generous bend radii (≥2 t); hot forming above ~900 °C should be followed by re-normalizing to restore the fine-grain properties.
What is the maximum service temperature of P285NH-N?
P285NH-N 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.
What is the difference between P285NH-N and P285NH-NR?
N is the default condition — standard supply condition for pressure vessel shells, heads and forgings requiring 285 MPa minimum yield and 40 J at -20 °C. NR: plate rolled so that the final pass leaves a normalized-equivalent structure — same guaranteed properties as +N without a separate furnace cycle, cheaper on heavy plate. Yield strength is 320 MPa in N versus 330 MPa in NR.
Sources
- EN 10028-3 — Flat products of steels for pressure purposes: weldable fine grain steels, normalized — CEN (2017)
- EN 10222-4 — Steel forgings for pressure purposes: weldable fine grain steels with high proof strength — CEN (2017)
- EN 10027-2 — Designation systems for steels: numerical system (1.0477) — CEN (2015)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- EN 13445-3 — Unfired pressure vessels: design (material physical data annex) — CEN (2021)
- 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.