Method for producing a nitrided packaging steel

The invention relates to a method for producing a nitrided packaging steel with a carbon content of 10 to 1000 ppm and an amount of uncombined nitrogen, dissolved in the steel, of more than 100 ppm, wherein the nitriding is performed in two stages, to be specific a first stage, in which a molten steel is nitrided to a nitrogen content of at most 160 ppm by introducing a nitrogen-containing gas and/or a nitrogen-containing solid into the molten steel, and a second stage, in which a flat steel product produced from the nitrided molten steel by cold rolling is treated with a nitrogen-containing gas in order to increase further the amount of uncombined nitrogen in the flat steel product. The second nitriding stage is in this case performed in an annealing furnace, in which the flat steel product is at the same time annealed in a recrystallizing manner. The packaging steels produced by this method are distinguished by great strength, in excess of 600 MPa, and good elongation to fracture, regularly in excess of 5%, as well as by good forming properties. The invention also relates to a nitrided packaging steel in the form of a flat steel product.