Process for producing a grain-orientated electrical steel sheet

US6153019A · kind A · utility

Assignee

• Thyssen Stahl AG · DE

Inventors

• Manfred Espenhahn · Essen, DE
• Andreas Böttcher · Mettmann, DE
• Klaus Gunther · Voerde, DE

Key dates

• Filing date: Oct 26, 1998
• Grant date: Nov 28, 2000
• Expiry date: Oct 26, 2018

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C21D8/1261
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A process for producing a grain-oriented magnetic steel sheet in which a slab, made from a steel containing (in mass %) more than 0.005 to 0.10% C, 2.5 to 4.5% Si, 0.03 to 0.15% Mn, more than 0.01 to 0.05% S, 0.01 to 0.035% Al, 0.0045 to 0.012% N, 0.02 to 0.3% Cu, the remainder being Fe, including unavoidable impurities, is heated through and hot rolled to a final thickness between 1.5 and 7.0 mm. The hot strip is annealed and immediately cooled and cold rolled in one or several cold-rolling steps to the final thickness of the cold strip. The cold strip is subjected to a recrystallizing annealing process in a humid atmosphere containing hydrogen and nitrogen, with synchronous decarburization. A non-stick layer, essentially containing MgO, is applied to the surface of the decarburized cold strip which is then subjected to final annealing. The cold strip is then rolled into coils.