Material number 1.4462: 1.4462
1.4462 is the European material number (Werkstoffnummer, EN 10027-2) for 1.4462, ferritic-austenitic (duplex) stainless steel specified in EN 10088-2.
What 1.4462 means
EN 10027-2 material numbers have the form 1.XXYY: the leading 1 is steel; the next two digits give the steel group (44 → stainless steels with ≥ 2.5 % Ni, with Mo); the last two digits are a sequential number within that group. The number is unique to one composition and survives name changes, which is why 1.4462 has stayed constant while the symbolic name moved from X2CrNiMoN22 5 3 to 1.4462.
1.4462 at a glance
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.
Full data sheet for 1.4462 → · Equivalent grades →