Aluminium-coated iron-chromium foil containing additions of rare earths or yttrium

摘要

An aluminium-coated ferritic stainless steel is provided which consists essentially of iron, 15-25% by weight of chromium, normal steelmaking impurities including up to about 0.03% sulphur, and an addition from the group consisting of cerium, lanthanum, neodymium, praseodymium and yttrium, wherein the atom ratio of the total addition from this group is at least one as compared to the sulphur content of the steel. Preferably the amount of aluminium within the ferritic stainless steel alloy is negligible. After strip, or foil, of appropriate thickness is produced from the alloy, it is coated with aluminium so as to obtain an average aluminium content within the composite material (which consists of the aluminium coating and the iron-chromium base metal) of approximately five weight percent. The aluminium-coated ferritic stainless steel alloy of this invention is characterized by superb oxidation resistance at elevated temperatures and good processability.