Title:
HIGH-STRENGTH STEEL SHEET, HIGH-STRENGTH GALVANIZED STEEL SHEET, METHOD FOR PRODUCING HIGH-STRENGTH STEEL SHEET, AND METHOD FOR PRODUCING HIGH-STRENGTH GALVANIZED STEEL SHEET
Document Type and Number:
WIPO Patent Application WO/2019/163513
Kind Code:
A1
Abstract:
The present invention relates to a high-strength steel sheet which satisfies a specific chemical component composition, and which is configured such that: if the metal structure thereof is observed with a scanning electron microscope, polygonal ferrite is 30-60% by area; if the metal structure thereof is observed with an optical microscope, MA mixed structure is 21% by area or less; if the metal structure thereof is measured by an X-ray diffraction method, residual austenite is 8% by volume or more; the area ratio of polygonal ferrite having a circle-equivalent diameter of 35.0 μm or more is 0% and the area ratio of polygonal ferrite having a circle-equivalent diameter of 10.0 μm or more but less than 35.0 μm is 10% or less in the polygonal ferrite; and the connectivity as defined by a specific relational expression is 10% or more.
Inventors:
IKEDA MUNEAKI
SAITO KENJI
SAITO KENJI
Application Number:
PCT/JP2019/004185
Publication Date:
August 29, 2019
Filing Date:
February 06, 2019
Export Citation:
Assignee:
KOBE STEEL LTD (JP)
International Classes:
C21D9/46; C22C38/00; C22C38/06
Domestic Patent References:
| WO2016158160A1 | 2016-10-06 | |||
| WO2015046364A1 | 2015-04-02 | |||
| WO2013047739A1 | 2013-04-04 |
Foreign References:
| JP2015113504A | 2015-06-22 | |||
| JP2008214752A | 2008-09-18 |
Attorney, Agent or Firm:
KOTANI, Etsuji et al. (JP)
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