Stahlblech, Element und Herstellungsverfahren dafür

Details

Veröffentlichungs-Nr.

EP4752250

Anmeldetag

3. Oktober 2024

Veröffentlichung

10. April 2025

Rechtsraum

EP

Abstract

To provide a technique for a steel sheet having a TS of 780 MPa or more and less than 1180 MPa, a high YS, and high press formability in the inner portion of the steel sheet and at an end portion of the steel sheet.In the steel sheet, a base steel sheet has a predetermined chemical composition and has a surface soft layer having a Vickers hardness of 84% or less with respect to that at the quarter thickness from the surface of the base steel sheet and satisfying the following formula (1),the surface soft layer has a microstructure in a specific range, the base steel sheet has a microstructure in a specific range at the quarter thickness, and the steel sheet has a tensile strength of 780 MPa or more and less than 1180 MPa.20≤X≤120−3800×Sb−1900×SnIn the formula (1), X denotes the thickness of the surface soft layer (µm), and [Sb] and [Sn] denote an Sb content and a Sn content of steel (% by mass), respectively.

Anmelder

Firma

JFE Steel Corporation

Land

🇯🇵 Japan