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:
Nov. 30, 2010
Filed:
Sep. 15, 2005
Kazuhisa Kusumi, Chiba-Ken, JP;
Hironori Sato, Chiba-Ken, JP;
Masayuki Abe, Chiba-Ken, JP;
Nobuhiro Fujita, Chiba-Ken, JP;
Noriyuki Suzuki, Chiba-Ken, JP;
Kunio Hayashi, Chiba-Ken, JP;
Shinya Nakajima, Chiba-Ken, JP;
Jun Maki, Chiba-Ken, JP;
Masahiro Oogami, Chiba-Ken, JP;
Toshiyuki Kanda, Chiba-Ken, JP;
Manabu Takahashi, Chiba-Ken, JP;
Yuzo Takahashi, Chiba-Ken, JP;
Kazuhisa Kusumi, Chiba-Ken, JP;
Hironori Sato, Chiba-Ken, JP;
Masayuki Abe, Chiba-Ken, JP;
Nobuhiro Fujita, Chiba-Ken, JP;
Noriyuki Suzuki, Chiba-Ken, JP;
Kunio Hayashi, Chiba-Ken, JP;
Shinya Nakajima, Chiba-Ken, JP;
Jun Maki, Chiba-Ken, JP;
Masahiro Oogami, Chiba-Ken, JP;
Toshiyuki Kanda, Chiba-Ken, JP;
Manabu Takahashi, Chiba-Ken, JP;
Yuzo Takahashi, Chiba-Ken, JP;
Nippon Steel Corporation, Chiyoda-ku, Tokyo, JP;
Abstract
High-strength parts and a method for producing them can be provided, where such parts exhibit hydrogen embrittlement resistance and strength after high-temperature forming. For example, the atmosphere in a heating furnace can contain less than about 10% hydrogen and/or have a dew point of about 30° C. or less. The amount of hydrogen penetrating a steel sheet during heating can thereby be reduced. After forming, quench hardening in a die assembly and post-working can be performed. Post-working can include shearing followed by re-shearing or compression forming; punching with a cutting blade having a continuously reduced base width; punching with a tool having a curved blade and a protrusion at the tip of the cutting blade, where the curved blade may include a shoulder portion of given radius and/or angle; fusion cutting; etc. Tensile residual stresses after punching can be reduced and resistance to hydrogen embrittlement can be improved.