Patents by Inventor Rintaro Ueji

Rintaro Ueji 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: 20180214974
    Abstract: Provided are a simple and effective friction welding method that can suppress increases in hardness of the welded part and reductions in hardness (strength) in the heat affected zone regardless of the composition of ferrous material, and a welded structure obtained with the same. The present invention relates to a friction welding method wherein surfaces to be welded of two metal members (2, 4) to be welded are made to slide in contact with each other. The friction welding method is characterized in that at least one of the metal members (2, 4) to be welded is a ferrous material, and the maximum temperature reached during welding is equal to or less than the A3 point or equal to or less than the Acm point of the ferrous material. The maximum temperature reached during welding is preferably equal to or less than the A1 point of the ferrous material.
    Type: Application
    Filed: July 11, 2016
    Publication date: August 2, 2018
    Applicant: OSAKA UNIVERSITY
    Inventors: Hidetoshi Fujii, Rintaro Ueji, Yoshiaki Morisada
  • Publication number: 20080178972
    Abstract: The present invention relates to A high strength steel sheet having a structure which is mainly composed of MD structure (Micro Duplex structure) comprising a ferrite matrix, and as a secondary phase, martensite or martensite and retained austenite, finely dispersed in said matrix, wherein the proportion that the MD structure occupies in the whole structure is 90% or more, wherein the proportion that the secondary phase present in the whole structure occupies in the whole structure is from 10 to 60%, wherein the secondary phase in the MD structure is present in ferrite grains and at grain boundary, in which the proportion of the secondary phase present in the ferrite grains is 50% or more, and wherein the average grain size of the secondary phase in the whole structure is 3 ?m or less. The secondary phase is constituted of martensite, or martensite and retained austenite.
    Type: Application
    Filed: October 16, 2007
    Publication date: July 31, 2008
    Applicants: KABUSHIKI KAISHA KOBE SEIKO SHO (KOBE STEEL, LTD), National University Corporation Kagawa University
    Inventors: Kenji SAITO, Tomokazu MASUDA, Toshio MURAKAMI, Koichi MAKII, Kazutoshi KUNISHIGE, Rintaro UEJI
  • Publication number: 20070084529
    Abstract: A high strength and high ductility low carbon steel having a tensile strength of 800 MPa or more, an uniform elongation of 5% or more, and an elongation to failure of 20% or more which is produced by a method comprising subjecting an ordinary low carbon steel or an ordinary low carbon steel added with boron in an amount being 0.01% or less and effective for accelerating martensitic transformation to processing and heat treatment to prepare a product having coarser size of austenite crystal grains and then to water-quenching, to provide a steel product having a martensite phase in an amount of 90% or more, and subjecting the steel product to a low strain processing, specifically a cold rolling at a total rolling reduction in thickness of 20% or more and less than 80%, and to a low temperature annealing at 500° C. to 600° C., and a method for producing said high strength and high ductility low carbon steel.
    Type: Application
    Filed: October 11, 2006
    Publication date: April 19, 2007
    Inventors: Yoshihiro Saito, Nobuhiro Tsuji, Rintaro Ueji
  • Publication number: 20040112484
    Abstract: A high strength and high ductility low carbon steel having a tensile strength of 800 MPa or more, an uniform elongation of 5% or more, and an elongation to failure of 20% or more which is produced by a method comprising subjecting an ordinary low carbon steel or an ordinary low carbon steel added with boron in an amount being 0.01% or less and effective for accelerating martensitic transformation to processing and heat treatment to prepare a product having coarser size of austenite crystal grains and then to water-quenching, to provide a steel product having a martensite phase in an amount of 90% or more, and subjecting the steel product to a low strain processing, specifically a cold rolling at a total rolling reduction in thickness of 20% or more and less than 80%, and to a low temperature annealing at 500° C. to 600° C., and a method for producing said high strength and high ductility low carbon steel.
    Type: Application
    Filed: September 11, 2003
    Publication date: June 17, 2004
    Inventors: Yoshihiro Saito, Tsuji Nobuhiro, Rintaro Ueji