Patent · US Active

Coated steel sheet and high strength press hardened steel part and method of manufacturing the same

US12385121B2 · kind B2 · utility

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Key dates

Filing dateDec 3, 2021
Grant dateAug 12, 2025
Priority date
Expiry dateDec 3, 2041

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC21D2211/008
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A coated steel sheet and press hardened steel part having a composition including, by weight percent: C 0.15-0.25%, Mn 0.5-1.8%, Si 0.1-1.25%, Al 0.01-0.1%, Cr 0.1-1.0%, Ti 0.01-0.1%, B 0.001-0.004%, P≤0.020%, S≤0.010%, N≤0.010% the remainder of the composition being iron and unavoidable impurities resulting from the smelting. The press hardened steel part includes a bulk having a microstructure including, in surface fraction, more than 95% of martensite and less than 5% of bainite, a coating layer at the surface of the steel part, a ferritic interdiffusion layer between the coating layer and the bulk, and a ratio between the ferritic grain width in the interdiffusion layer GWint over prior austenite grain size in the bulk PAGSbulk, satisfying following equation (GWint/PAGSbulk)−1≥30%.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.