Method for producing a cold-rolled flat steel product for deep-drawing and ironing applications, flat steel product, and use of a flat steel product of said type

US10184159B2 · kind B2 · utility

Assignees

• ThyssenKrupp Steel Europe AG · DE
• thyssenkrupp Rasselstein GmbH · DE

Inventors

• Erhard Holleck · Duisburg, DE
• Eberhard Sowka · Dinslaken, DE
• Burkhard Kaup · Andernach, DE
• Stephan Schiester · Andernach, DE

Key dates

• Filing date: Mar 6, 2014
• Grant date: Jan 22, 2019
• Expiry date: Mar 20, 2035

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B21D51/26
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A method is disclosed for the operationally reliable production of a cold-rolled flat steel product of ≤0.5 mm in thickness for deep-drawing and ironing applications. In the method, a steel melt which (in wt %) comprises up to 0.008% C, up to 0.005% Al, up to 0.043% Si, 0.15-0.5% Mn, up to 0.02% P, up to 0.03% S, up to 0.020% N and in each case optionally up to 0.03% Ti and up to 0.03% Nb and, as a remainder, iron and unavoidable impurities, is, with the omission of a Ca treatment, subjected to a secondary metallurgical treatment which, in addition to a vacuum treatment, comprises a ladle furnace treatment and during which the steel melt to be treated is kept under a slag, the Mn and Fe contents of which are, in sum total, <15 wt %. From the steel melt, a thin slab or a cast strip are produced, which are subsequently hot-rolled to form a hot strip with a thickness of <2.5 mm and wound to form a coil. Subsequently, the hot strips are cold-rolled to form a flat steel product of up to 0.5 mm in thickness.