The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 15, 2020
Filed:
Jun. 29, 2012
Norio Imai, Osaka, JP;
Masayuki Wakita, Osaka, JP;
Takuya Nishio, Osaka, JP;
Jun Haga, Osaka, JP;
Kengo Hata, Osaka, JP;
Yasuaki Tanaka, Osaka, JP;
Mitsuru Yoshida, Osaka, JP;
Hiroshi Takebayashi, Osaka, JP;
Suguhiro Fukushima, Osaka, JP;
Toshiro Tomida, Osaka, JP;
Norio Imai, Osaka, JP;
Masayuki Wakita, Osaka, JP;
Takuya Nishio, Osaka, JP;
Jun Haga, Osaka, JP;
Kengo Hata, Osaka, JP;
Yasuaki Tanaka, Osaka, JP;
Mitsuru Yoshida, Osaka, JP;
Hiroshi Takebayashi, Osaka, JP;
Suguhiro Fukushima, Osaka, JP;
Toshiro Tomida, Osaka, JP;
NIPPON STEEL CORPORATION, Tokyo, JP;
Abstract
A hot-dip galvanized cold-rolled steel sheet has a tensile strength of 750 MPa or higher, a composition consisting, in mass percent, C: more than 0.10% and less than 0.25%, Si: more than 0.50% and less than 2.0%, Mn: more than 1.50% and 3.0% or less, and optionally containing one or more types of Ti, Nb, V, Cr, Mo, B, Ca, Mg, REM, and Bi, P: less than 0.050%, S: 0.010% or less, sol. Al: 0.50% or less, and N: 0.010% or less, and a main phase as a low-temperature transformation product and a second phase as retained austenite. The retained austenite volume fraction is more than 4.0% and less than 25.0% of the whole structure, and has an average grain size of less than 0.80 μm. A number density of retained austenite grains having a grain size of 1.2 μm or more is 3.0×10/μmor less.