Abstract: A method for producing a steel sheet having a two-layer recrystallization structure includes: providing a cold-rolled steel sheet made of a steel with a carbon content of 10 to 1000 ppm, based on the weight, and a specified recrystallization temperature; applying a barrier layer which is at least partly impermeable to nitrogen onto a first face; and heating the steel sheet to a heating temperature. The heating is carried out at least temporarily in a nitrogenizing gas atmosphere at least until the recrystallization temperature is reached, whereby nitrogen from the gas atmosphere is diffused at least in a region near the surface on a second face of the steel sheet upon heating and is stored in the region, whereby the recrystallization temperature of the steel is raised in the region. The heating temperature is higher than or equal to the specified recrystallization temperature and lower than the raised recrystallization temperature.

Abstract: A method for producing a steel sheet for packaging includes: cold-rolling a hot-rolled steel sheet made from a steel having a carbon content of 10 to 1000 ppm by weight, the steel of the hot-rolled steel sheet having a predetermined recrystallization temperature (TR); heating the cold-rolled steel sheet to a predetermined heating temperature (TE), where TR?TE, the heating performed at least partially in the presence of a nitrogen donor at least until TR is reached such that when the cold-rolled steel sheet is heated, nitrogen from the nitrogen donor is diffused at least into a near-surface region of the cold-rolled sheet steel and incorporated in the near-surface region, as a result of which the TR in the near-surface region is increased by a value ?T, where TE<TR+?T. Using this method, high-strength steel sheets having a multilayer microstructure can be produced.