1.4462 steel (1.4462): properties, composition, equivalents

1.4462 (X2CrNiMoN22-5-3) is the standard duplex 2205 in EN 10088: 22 % Cr, 5 % Ni, 3 % Mo, 0.15 % N. 450–460 MPa yield, 640–840 MPa tensile, PREN ≈ 35. Data, limits and the 2205/S31803/S32205 equivalence.

What is 1.4462?

1.4462 (X2CrNiMoN22-5-3) is the standard duplex stainless steel — the grade the world calls 2205. Its microstructure is half ferrite, half austenite, and that balance gives twice the yield strength of 316L (460 MPa vs 220 MPa), better chloride stress-corrosion cracking resistance and a pitting index PREN of about 35 against 24 for 1.4404. Nitrogen (0.10–0.22 %) is the key alloying element: it stabilizes the austenite, raises PREN and speeds re-formation of austenite in weld metal.

Because designers can halve the wall thickness compared with austenitic steel, 1.4462 is the economic choice for pressure vessels, storage tanks, heat exchangers, offshore piping, desalination and pulp-and-paper digesters. The limits are temperature: intermetallic phases (sigma, chi) form on holding at 700–950 °C and 475 °C embrittlement occurs on long exposure at 350–500 °C, so the practical service window is −50 to +280 °C (EN 13445 / ASME: 315 °C).

Since 2000 most 2205 is melted to the tighter UNS S32205 window, which 1.4462 plate normally meets; the older S31803 window is wider on the low side. The table grades both, plus the JIS, GB and forging (F51/F60) designations.

1.4462 chemical composition

EN 10088-2:2014 Table 4. ASTM S32205 ("2205" since 2000) requires Cr 22–23, Mo 3.0–3.5, N 0.14–0.20 — a tighter, higher-PREN window inside the EN range; older S31803 is wider (Cr 21–23, Mo 2.5–3.5, N 0.08–0.20).

1.4462 mechanical properties

Solution annealed 1020–1100 °C, water quenched. Roughly 50/50 ferrite/austenite; ferromagnetic. Impact ≥ 100 J at +20 °C and ≥ 40 J at −40 °C typical for plate.

Impact toughness

1.4462 requires a minimum Charpy V-notch energy of 40 J at -40 °C (typical plate; EN 10028-7 requires ≥ 60 J at −40 °C for pressure plate ≤ 30 mm). Duplex steels have a ductile-to-brittle transition; the practical lower service limit is −50 °C (ASME: −40 °F).

1.4462 equivalent grades

Identical = same composition and mechanical limits within rounding. Near = one limit differs (e.g. carbon max or impact temperature). Functional = interchangeable for most uses after an engineering check. Full cross-reference for 1.4462 →

Old and superseded designations

Product forms and tolerance standards

Product forms: hot-rolled plate (dominant), cold-rolled sheet and coil, bar and forgings (EN 10088-3, EN 10222-5), seamless and welded pipe (EN 10216-5, EN 10217-7), fittings and flanges.

Dimensional tolerances: plate: EN 10029; cold-rolled: EN ISO 9445-2; bar: EN 10278 / EN 10060.

Key property values

1.4462 yield strength

Rp0.2 ≥ 460 MPa hot-rolled plate (67 ksi), ≥ 500 MPa cold-rolled sheet, ≥ 450 MPa bar; Rp1.0 ≥ 500 MPa. EN 1993-1-4 uses fy = 460 MPa (plate).

1.4462 tensile strength

640–840 MPa plate (93–122 ksi), 700–950 MPa strip and cold-rolled sheet.

1.4462 hardness

Max 270 HB (≈ 28 HRC) solution annealed; NACE MR0175 limits to 28 HRC / 36 HRC depending on product form for sour service. Not hardenable by heat treatment.

Corrosion resistance

PREN = Cr + 3.3 Mo + 16 N ≈ 34–36 (S32205 heats ≥ 35). CPT (ASTM G48 A) ≈ 35–50 °C; CCT ≈ 20 °C. Resistant to chloride SCC up to ~150 °C where 316L fails at 60 °C. Suitable for seawater at ambient temperature with flow; crevices need super-duplex.

Physical properties

Density 7.8 g/cm³, E = 200 GPa, expansion 13 × 10⁻⁶/K (20–100 °C — closer to carbon steel than austenitics), conductivity 15 W/m·K, ferromagnetic.

Heat treatment

Solution anneal 1020–1100 °C, water quench. Never stress-relieve at 350–950 °C (embrittlement). Hot forming 1200–950 °C followed by full re-anneal.

Weldability

Weldable by TIG, MIG, MMA, SAW and FCAW with over-alloyed filler 22 9 3 N L (ER2209, 9 % Ni) to keep the weld metal ≥ 30 % austenite. Heat input 0.5–2.5 kJ/mm, interpass ≤ 150 °C (100 °C for thick sections), no preheat, no PWHT. Purge roots with argon + 2 % N₂. Autogenous welding without filler produces a ferritic, brittle bead and is not permitted for pressure parts.

Machining, forming and heat treatment

Machinability ≈ 30 % (high yield strength and work hardening): rigid set-ups, carbide with sharp positive geometry, low speed / high feed, abundant coolant. Cold forming requires ~50 % higher press force than 316L and generous bend radii (≥ 2 t); spring-back is large. Hot forming 1200–950 °C then solution anneal.

Typical applications

• Pressure vessels, columns and storage tanks (EN 13445, ASME VIII with S32205)
• Heat exchangers, condensers and evaporators in chloride-containing water
• Offshore process piping, risers, firewater systems, umbilical tubes
• Desalination (SWRO) high-pressure piping and vessels
• Pulp and paper digesters, bleach plant, white-liquor tanks
• Chemical tankers cargo tanks, road tankers
• Bridges, walkways and rebar in marine or de-icing environments
• Flue-gas desulphurization and wet scrubbers

Frequently asked questions

Related grades

Verified against EN 10088-2:2014; EN 10088-2:2014 Tables 4 and 13; EN 10028-7:2016; ASTM A240/A240M-22 (S31803/S32205 comparison). Last checked: September 2026.