ACCIAIO FERRITICO AL CROMO-MOLIBDE NO-NICHEL RESISTENTE ALLA CORROSIONE

Described herein is a ferritic chrome-molybdenum-nickel steel, containing specified amounts of niobium, zirconium and aluminum, of high chemical resistance against general and intercrystalline corrosion attack, as well as against pitting, crevice and stress corrosion in chloride-containing solutions. The described steel is useful for the fabrication of articles which must exhibit a 0.2-limit of at least 520 N/mm2 at room temperature; a notched bar impact strength of at least 40 J at 0 DEG C. and at least 70 J at 20 DEG C. in 3-mm U-notch impact specimens; and guaranteed for flat stock such as sheet or strip material up to at least 10 mm thickness and for bar material of at least 60 mm diameter, round of square.