Title:
HOT ROLLED STEEL SHEET AND METHOD FOR MANUFACTURING SAME
Document Type and Number:
WIPO Patent Application WO/2019/031583
Kind Code:
A1
Abstract:
A hot rolled steel sheet according to an embodiment of the present invention is configured such that: the hot rolled steel sheet has prescribed chemical components; the metal structure in a center position in the sheet width at 1/4 the depth of sheet thickness is formed of 90% by volume or greater martensite with the remaining structure being 0 – 10% by volume; the remaining structure is either one or both of bainite or ferrite; the average length of crystal grains in direction L is 0.2 – 5.0 µm, the average length of crystal grains in direction C is 0.1 – 5.0 µm, and the ratio of C direction grain lengths, which are the average lengths for the crystal grains in the direction C, to the L direction grain lengths, which are the average length for crystal grains in the direction L, is 0.2 ≤ C direction grain lengths/L direction grain lengths ≤ 5.0; and tensile strength is 1180 MPa or greater.
Inventors:
HIRASHIMA TETSUYA (JP)
TOYODA TAKESHI (JP)
TOYODA TAKESHI (JP)
Application Number:
PCT/JP2018/029920
Publication Date:
February 14, 2019
Filing Date:
August 09, 2018
Export Citation:
Assignee:
NIPPON STEEL & SUMITOMO METAL CORP (JP)
International Classes:
C22C38/00; C21D9/46; C22C38/14; C22C38/16; C22C38/58
Foreign References:
| JP2013011068A | 2013-01-17 | |||
| JP2014227583A | 2014-12-08 | |||
| JP2011052321A | 2011-03-17 | |||
| JP2017179540A | 2017-10-05 | |||
| JP2017154294A | 2017-09-07 | |||
| JPH05345917A | 1993-12-27 | |||
| JP2014205889A | 2014-10-30 | |||
| JP2011052321A | 2011-03-17 |
Other References:
See also references of EP 3666916A4
Attorney, Agent or Firm:
TANAI Sumio et al. (JP)
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