Patents by Inventor Shotaro TERASHIMA

Shotaro TERASHIMA has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20220251676
    Abstract: Provided are a high-strength hot-dip galvanized steel sheet that has a tensile strength of 1180 MPa or more and excellent ductility, stretch flangeability, bendability and LME resistance and can manufacture parts with high dimensional accuracy, and its manufacturing method. The high-strength steel sheet with a tensile strength of 1180 MPa or more has a chemical composition containing C, Si, Mn, P, S, Al and N, with [% Si], [% Mn], [% P], [% Mo] and [% Cr] satisfying a predetermined relationship and the balance being Fe and inevitable impurities, and a steel microstructure including ferrite, tempered martensite and bainite, and retained austenite, where the diffusible hydrogen amount in the steel sheet is 0.60 mass ppm or less, a thickness of softened surface layer is 5 ?m or more and 150 ?m or less, and a frequency of coincidence boundary in the steel sheet surface layer after a high-temperature tensile test is 0.45 or less.
    Type: Application
    Filed: June 19, 2020
    Publication date: August 11, 2022
    Applicant: JFE STEEL CORPORATION
    Inventors: Hidekazu MINAMI, Takeshi YOKOTA, Yoshiyasu KAWASAKI, Shotaro TERASHIMA
  • Patent number: 11248277
    Abstract: A method for manufacturing a high-strength galvanized steel sheet having excellent strength-elongation balance, coating adhesiveness, and surface appearance. The method includes: (i) a first heating process of heating a steel sheet having a predetermined chemical composition, (ii) a first pickling process of pickling the steel sheet which was subjected to the first heating process in an oxidizing acidic aqueous solution, (iii) a second pickling process of pickling the steel sheet which was subjected to the first pickling process in a non-oxidizing acidic aqueous solution, (iv) a second heating process of holding the steel sheet, which was subjected to the second pickling process, at a temperature range of 700° C. or higher and 900° C. or lower in a hydrogen-containing atmosphere for 20 seconds or more and 300 seconds or less, and (v) performing a galvanizing treatment on the steel sheet which was subjected to the second heating process.
    Type: Grant
    Filed: April 24, 2018
    Date of Patent: February 15, 2022
    Assignee: JFE STEEL CORPORATION
    Inventors: Shotaro Terashima, Yusuke Fushiwaki, Yoichi Makimizu, Hiroyuki Masuoka, Hiroshi Hasegawa
  • Publication number: 20200199705
    Abstract: A method for manufacturing a high-strength galvanized steel sheet having excellent strength-elongation balance, coating adhesiveness, and surface appearance. The method includes: (i) a first heating process of heating a steel sheet having a predetermined chemical composition, (ii) a first pickling process of pickling the steel sheet which was subjected to the first heating process in an oxidizing acidic aqueous solution, (iii) a second pickling process of pickling the steel sheet which was subjected to the first pickling process in a non-oxidizing acidic aqueous solution, (iv) a second heating process of holding the steel sheet, which was subjected to the second pickling process, at a temperature range of 700° C. or higher and 900° C. or lower in a hydrogen-containing atmosphere for 20 seconds or more and 300 seconds or less, and (v) performing a galvanizing treatment on the steel sheet which was subjected to the second heating process.
    Type: Application
    Filed: April 24, 2018
    Publication date: June 25, 2020
    Applicant: JFE STEEL CORPORATION
    Inventors: Shotaro TERASHIMA, Yusuke FUSHIWAKI, Yoichi MAKIMIZU, Hiroyuki MASUOKA, Hiroshi HASEGAWA