Title:
STEEL SHEET AND PLATED STEEL SHEET
Document Type and Number:
WIPO Patent Application WO/2018/026016
Kind Code:
A1
Abstract:
This steel sheet has a specific chemical composition and is provided with a structure represented by, in terms of area ratio, 0–30% ferrite and 70–100% bainite. When a crystal grain is defined as a region which is surrounded by grain boundaries having a misorientation of 15° or higher and for which the equivalent circle diameter is 0.3 μm or larger, the proportion of crystal grains having an intragranular misorientation of 5–14° relative to all of the crystal grains is 20–100% in terms of area ratio. The grain boundary number density of a solid solution of C, or the total grain boundary number density of a solid solution of C and a solid solution of B is 1 particle/nm2 to 4.5 particles/nm2 inclusive. The average particle size of cementite precipitated in the grain boundaries is no larger than 2 μm.
Inventors:
SANO KOHICHI (JP)
UNO MAKOTO (JP)
NISHIYAMA RYOICHI (JP)
YAMAGUCHI YUJI (JP)
SUGIURA NATSUKO (JP)
NAKATA MASAHIRO (JP)
UNO MAKOTO (JP)
NISHIYAMA RYOICHI (JP)
YAMAGUCHI YUJI (JP)
SUGIURA NATSUKO (JP)
NAKATA MASAHIRO (JP)
Application Number:
PCT/JP2017/028481
Publication Date:
February 08, 2018
Filing Date:
August 04, 2017
Export Citation:
Assignee:
NIPPON STEEL & SUMITOMO METAL CORP (JP)
International Classes:
C22C38/00; C22C38/58; C21D9/46
Domestic Patent References:
| WO2008123366A1 | 2008-10-16 | |||
| WO2014002941A1 | 2014-01-03 | |||
| WO2014014120A1 | 2014-01-23 | |||
| WO2008056812A1 | 2008-05-15 |
Foreign References:
| JP2009019265A | 2009-01-29 |
Other References:
See also references of EP 3495530A4
Attorney, Agent or Firm:
KOKUBUN, Takayoshi (JP)
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