Patents by Inventor Yasunori Iwasa

Yasunori Iwasa 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).

  • Patent number: 11371110
    Abstract: A cold-rolled steel according to the present invention has a predetermined chemical composition, satisfies (5×[Si]+[Mn])/[C]>10 when [C] is the amount of C by mass %, [Si] is the amount of Si by mass %, and [Mn] is the amount of Mn by mass %, includes 40% to 95% ferrite and 5% to 60% martensite in area fraction, and optionally further includes 10% or less pearlite in area fraction, 5% or less retained austenite in volume fraction, and less than 40% bainite in area fraction. The total of the area fraction of ferrite and the area fraction of martensite is 60% or more, the hardness of martensite measured with a nanoindenter satisfies H2/H1<1.10 and ?HM<20.
    Type: Grant
    Filed: December 6, 2019
    Date of Patent: June 28, 2022
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Yoshihiro Suwa, Toshiki Nonaka, Koichi Sato, Manabu Naruse, Yasunori Iwasa, Yoshifumi Kobayashi
  • Publication number: 20200109458
    Abstract: A cold-rolled steel according to the present invention has a predetermined chemical composition, satisfies (5×[Si]+[Mn])/[C]>10 when [C] is the amount of C by mass %, [Si] is the amount of Si by mass %, and [Mn] is the amount of Mn by mass %, includes 40% to 95% ferrite and 5% to 60% martensite in area fraction, and optionally further includes 10% or less pearlite in area fraction, 5% or less retained austenite in volume fraction, and less than 40% bainite in area fraction. The total of the area fraction of ferrite and the area fraction of martensite is 60% or more, the hardness of martensite measured with a nanoindenter satisfies H2/H1<1.10 and ?HM<20.
    Type: Application
    Filed: December 6, 2019
    Publication date: April 9, 2020
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Yoshihiro SUWA, Toshiki NONAKA, Koichi SATO, Manabu NARUSE, Yasunori IWASA, Yoshifumi KOBAYASHI
  • Patent number: 10544475
    Abstract: A hot-stamped steel according to the present invention has a predetermined chemical composition, satisfies (5×[Si]+[Mn])/[C]>10 when [C] is the amount of C by mass %, [Si] is the amount of Si by mass %, and [Mn] is the amount of Mn by mass %, includes 40% to 95% ferrite and 5% to 60% martensite in area fraction, and optionally further includes 10% or less pearlite in area fraction, 5% or less retained austenite in volume fraction, and less than 40% bainite in area fraction. The total of the area fraction of ferrite and the area fraction of martensite is 60% or more, the hardness of martensite measured with a nanoindenter satisfies H2/H1<1.10 and ?HM<20, and TS×? which is product of tensile strength TS and hole expansion ratio ? is 50000 MPa·% or more.
    Type: Grant
    Filed: March 27, 2014
    Date of Patent: January 28, 2020
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Yoshihiro Suwa, Toshiki Nonaka, Koichi Sato, Manabu Naruse, Yasunori Iwasa, Yoshifumi Kobayashi
  • Publication number: 20160060722
    Abstract: A hot-stamped steel according to the present invention has a predetermined chemical composition, satisfies (5×[Si]+[Mn])/[C]>10 when [C] is the amount of C by mass %, [Si] is the amount of Si by mass %, and [Mn] is the amount of Mn by mass %, includes 40% to 95% ferrite and 5% to 60% martensite in area fraction, and optionally further includes 10% or less pearlite in area fraction, 5% or less retained austenite in volume fraction, and less than 40% bainite in area fraction. The total of the area fraction of ferrite and the area fraction of martensite is 60% or more, the hardness of martensite measured with a nanoindenter satisfies H2/H1<1.10 and ?HM<20, and TS×? which is product of tensile strength TS and hole expansion ratio ? is 50000 MPa·% or more.
    Type: Application
    Filed: March 27, 2014
    Publication date: March 3, 2016
    Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Yoshihiro SUWA, Toshiki NONAKA, Koichi SATO, Manabu NARUSE, Yasunori IWASA, Yoshifumi KOBAYASHI
  • Publication number: 20090184446
    Abstract: In a polymer film stretching system, a tentering machine draws polymer film of cellulose acylate containing additive of triphenyl phosphate in a transverse direction while the polymer film is guided continuously and heated. A stretching chamber contains the tentering machine. A far infrared heater and heat roller heat the polymer film before entry to the stretching chamber to set temperature of the polymer film upon entry to the stretching chamber in a range equal to or higher than T+10 (deg. C.) and equal to or lower than T+80 (deg. C.), where T (deg. C.) is a condensation temperature of the additive evaporated in the stretching chamber. Furthermore, a film dispenser supplies the polymer film from a film roll to the tentering machine.
    Type: Application
    Filed: January 22, 2009
    Publication date: July 23, 2009
    Applicant: FUJIFILM Corporation
    Inventors: Masaki KAWATA, Yasunori Iwasa, Nobuyoshi Suzuki, Shinsuke Aoshima