Patents Assigned to NIPPON KOSHUHU STEEL CO LTD
  • Publication number: 20140023740
    Abstract: A press-forming mold has a protective film for preventing seizing during press-forming formed on at least a forming surface that comes into contact with a formed body. The protective film is formed by PVD. An arbitrary selection section extracted from the surface of the protective film is divided into a plurality of individual sections; and, when the gradient of the surface at the nth division point is represented by (dZn/dXn), taking N to represent the number of divisions, the root-mean-square R?q calculated by the following numerical expression is no greater than 0.032. R ? ? ? ? ? q = 1 N ? ? n = 1 N ? ? ( ? Z n ? X n ) 2 It is thereby possible to improve the seizing resistance of a press-forming mold having a protective film formed by PVD.
    Type: Application
    Filed: April 3, 2012
    Publication date: January 23, 2014
    Applicants: KABUSHIKI KAISHA KOBE SEIKO SHO (KOBE STEEL, LTD), NIPPON KOSHUHU STEEL CO LTD
    Inventors: Takaharu Kashi, Kenji Yamamoto