Global Patent Index - EP 4286544 A1

EP 4286544 A1 20231206 - STEEL SHEET FOR HOT STAMPING AND HOT STAMPING MOLDED BODY

Title (en)

STEEL SHEET FOR HOT STAMPING AND HOT STAMPING MOLDED BODY

Title (de)

STAHLBLECH FÜR HEISSPRÄGUNG UND HEISSPRÄGUNG EINES FORMKÖRPERS

Title (fr)

TÔLE D'ACIER POUR ESTAMPAGE À CHAUD, ET CORPS MOULÉ PAR ESTAMPAGE À CHAUD

Publication

EP 4286544 A1 20231206 (EN)

Application

EP 22807432 A 20220509

Priority

  • JP 2021081620 A 20210513
  • JP 2022019656 W 20220509

Abstract (en)

This steel sheet for hot stamping has a predetermined chemical composition and has a microstructure in which S<sub>α</sub> + S<sub>GB</sub>, which is a total of an area ratio S<sub>α</sub> of ferrite and an area ratio S<sub>GB</sub> of a granular bainite, is 10% or more and less than 50% and S<sub>GB</sub>/S<sub>α</sub>, which is a ratio between the area ratio S<sub>GB</sub> of the granular bainite and the area ratio S<sub>α</sub> of the ferrite, is 0.30 to 0.70. In addition, a hot-stamping formed body manufactured using this steel sheet for hot stamping has a predetermined chemical composition and a microstructure in which an average grain size of prior austenite grains is 5 to 25 µm, and a standard deviation of grain sizes of the prior austenite grains is 0.1 to 2.0 µm, and a tensile strength of the hot-stamping formed body is 2,200 MPa or more.

IPC 8 full level

C21D 9/00 (2006.01); C21D 1/18 (2006.01); C21D 9/46 (2006.01); C22C 38/00 (2006.01); C22C 38/60 (2006.01)

CPC (source: EP KR US)

C21D 1/02 (2013.01 - EP); C21D 1/18 (2013.01 - EP KR); C21D 1/673 (2013.01 - EP); C21D 7/13 (2013.01 - EP); C21D 8/0205 (2013.01 - EP); C21D 8/0226 (2013.01 - EP); C21D 9/46 (2013.01 - EP KR US); C22C 38/001 (2013.01 - KR); C22C 38/005 (2013.01 - EP); C22C 38/008 (2013.01 - EP KR); C22C 38/02 (2013.01 - EP US); C22C 38/04 (2013.01 - EP); C22C 38/06 (2013.01 - EP US); C22C 38/22 (2013.01 - EP); C22C 38/26 (2013.01 - EP); C22C 38/28 (2013.01 - EP); C22C 38/30 (2013.01 - EP); C22C 38/32 (2013.01 - EP); C22C 38/38 (2013.01 - EP US); C22C 38/42 (2013.01 - KR); C22C 38/44 (2013.01 - KR); C22C 38/46 (2013.01 - KR); C22C 38/48 (2013.01 - EP KR); C22C 38/50 (2013.01 - EP KR); C22C 38/52 (2013.01 - KR); C22C 38/54 (2013.01 - EP KR); C22C 38/58 (2013.01 - EP KR); C22C 38/60 (2013.01 - EP); C21D 2211/001 (2013.01 - KR US); C21D 2211/002 (2013.01 - EP KR US); C21D 2211/005 (2013.01 - EP KR US)

Designated contracting state (EPC)

AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

Designated extension state (EPC)

BA ME

Designated validation state (EPC)

KH MA MD TN

DOCDB simple family (publication)

EP 4286544 A1 20231206; EP 4286544 A4 20240731; CN 116917524 A 20231020; JP WO2022239731 A1 20221117; KR 20230137436 A 20231004; MX 2023010146 A 20230911; US 2024183015 A1 20240606; WO 2022239731 A1 20221117

DOCDB simple family (application)

EP 22807432 A 20220509; CN 202280018830 A 20220509; JP 2022019656 W 20220509; JP 2023521010 A 20220509; KR 20237029584 A 20220509; MX 2023010146 A 20220509; US 202218279370 A 20220509