Material number 1.4571: 1.4571
1.4571 is the European material number (Werkstoffnummer, EN 10027-2) for 1.4571, austenitic Cr-Ni-Mo stainless steel, titanium-stabilized specified in EN 10088-2.
What 1.4571 means
EN 10027-2 material numbers have the form 1.XXYY: the leading 1 is steel; the next two digits give the steel group (45 → stainless steels with special additions); 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 1.4571 has stayed constant while the symbolic name moved from X10CrNiMoTi18 10 to 1.4571.
1.4571 at a glance
1.4571 (X6CrNiMoTi17-12-2) is the titanium-stabilized member of the 316 family and, with 1.4404, one of the two grades German engineers mean by "V4A". Instead of driving carbon down to 0.03 %, the mill adds titanium at five times the carbon content; the carbon precipitates as harmless TiC during hot rolling, so the 17 % Cr / 2.2 % Mo matrix keeps its full corrosion resistance after welding or after service at 400–550 °C.
That heat stability is the reason 1.4571 remains the specified grade in German, Austrian and Eastern-European pressure-vessel, exhaust, flue-gas and chemical plant drawings (EN 10028-7, AD 2000). Strength is 10–20 MPa above 1.4404, creep strength is markedly better, and PREN is the same ≈ 24.
The price is surface quality: titanium carbonitride stringers show as fine streaks after bright polishing and can nucleate pits in thin sheet, so hygienic and decorative applications moved to 1.4404. Outside Europe, 316Ti is rare — ASTM lists it as S31635 but US mills stock 316L — and the cross-reference table explains what to accept as a substitute.
Full data sheet for 1.4571 → · Equivalent grades →