Schweissverbindung und Verbindungsstruktur für ein Automobilelement

Details

Veröffentlichungs-Nr.

EP4748956

Anmeldetag

12. Juli 2024

Veröffentlichung

23. Januar 2025

Rechtsraum

EP

Abstract

The present invention has as its technical issue the provision of a welded joint suppressing LME at the time of production. The welded joint of the present invention is a welded joint comprising a plurality of steel sheets which are overlaid and a spot welded part joining the plurality of steel sheets, wherein the spot welded part has a nugget, an indentation, and a weld shoulder part, at least one of the steel sheets among the plurality of steel sheets is a plated steel sheet, at least one of the steel sheets forming the overlaid surface among the plurality of steel sheets is a high strength steel sheet having a predetermined chemical composition, in a first region, a surface roughness Ra of the high strength steel sheet is 3.0 µm or less, a depth in a thickness direction from the surface of the high strength steel sheet wherein a C concentration is 0.02% or less is 3 µm or more, in grazing incidence X-ray diffraction with an incidence angle of 1° with respect to the surface of the high strength steel sheet, 0.45 ≤ 1(110) / ( I(110) + I(200) + I(211) ) ≤ 0.90 is satisfied, when I(110) denotes a diffraction intensity corresponding to the (110) plane, I(200) denotes a diffraction intensity corresponding to the (200) plane, and I(211) denotes a diffraction intensity corresponding to the (211) plane, and, in a second region of the high strength steel sheet, a thickness in a thickness direction from the surface of the high strength steel sheet of a layer having an area ratio of ferrite of 90% or more is 3 µm or more.

Anmelder

Firma

Nippon Steel Corporation

Land

🇯🇵 Japan