Cold rolled flat steel product for packaging and method for producing a steel flat product

US11920206B2 · kind B2 · utility

Assignee

• thyssenkrupp Rasselstein GmbH · DE

Inventors

• Burkhard Kaup · Andernach, DE
• Peter Kirchesch · Koblenz, DE
• Manuel KÖHL · Menning, DE
• Dimitrios Nouskalis · Burgbrohl, DE
• Alexander Gossen · Rengsdorf, DE
• Björn Ehmke · Sankt Johann, DE

Key dates

• Filing date: Oct 3, 2022
• Grant date: Mar 5, 2024
• Expiry date: Oct 3, 2042

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P10/25
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A cold rolled steel flat product for packaging made of a low carbon steel having a thickness of less than 0.49 mm and a method of making. The steel flat product has a martensite-free microstructure and represents a standard grade for packaging with tensile strengths from 300 to 550 MPa, which can be produced from a cold-rolled steel sheet with a carbon content from 0.01% to 0.1% by weight by inductive annealing of the steel sheet and subsequent water cooling for quenching the recrystallization-annealed steel sheet. To achieve flatness of 5 I-units or less, the induction annealed steel sheet is first primarily cooled in the manufacturing process to a take-off temperature at a rate of less than 1000 K/s, with the take-off temperature being below the transformation temperature of 723° C., and thereafter a secondary cooling by water cooling with a water temperature of less than 80° C. at a rate of more than 1000 K/s.