High-strength hot-dip galvanized steel sheet having excellent surface quality and electric resistance spot weldability, and manufacturing method therefor
US12371770B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 17, 2021 |
| Grant date | Jul 29, 2025 |
| Priority date | — |
| Expiry date | Jan 14, 2042 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC21D2221/02
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A hot-dip galvanized steel sheet according to one aspect of the present invention comprises a base steel sheet and a hot-dip galvanized layer formed on the surface of the base steel sheet, wherein the difference between the average of the Mn/Si values of surface oxides present on a surface portion, which is the region from the interface between the hot-dip galvanized layer and the base steel sheet to a depth of 15 nm, and the average of the Mn/Si values of internal oxides, which are present in the region from the interface to a depth of 50-100 nm, can be 0.5 or more. Mn and Si of each oxide mean the amounts (wt %) of Mn and Si components in the oxide, which are measured by EDS, and the average of Mn/Si values means the averaged value of the Mn/Si values measured for each oxide.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.