公开(公告)号：US20170337304A1

公开(公告)日：2017-11-23

申请号：US15527086

申请日：2015-11-04

Applicant: JFE STEEL CORPORATION

Inventor： Toru MINOTE ,  Tatsuya NAKAGAITO ,  Yuichi TOKITA ,  Yoshikiyo TAMAI

IPC: G06F17/50 ,  C21D1/673 ,  B21D22/02

CPC classification number: G06F17/5009 ,  B21D22/022 ,  C21D1/673 ,  G01N3/28 ,  G01N2203/0218 ,  G06F17/5018 ,  G06F17/5086 ,  G06F2217/42

Abstract: A method of evaluating a hot stamped part manufactured by hot stamping a coated steel sheet having a Zn—Ni coating layer on a surface of a base steel sheet includes an analysis model setting step, a forming condition setting step, a forming analysis step, and an evaluation step which are performed using a computer, wherein in the evaluation step, a maximum micro-crack depth in the hot stamped part manufactured under a forming condition set in the forming condition setting step is evaluated using a correlation, obtained beforehand, between an equivalent plastic strain in a surface layer of the hot stamped part and the maximum micro-crack depth in the hot stamped part.

公开(公告)号：US20180195144A1

公开(公告)日：2018-07-12

申请号：US15531573

申请日：2015-09-08

Applicant: JFE STEEL CORPORATION ,  TOYOTA JIDOSHA KABUSHIKI KAISHA

Inventor： Masaki MORINO ,  Hideaki KOBIKI ,  Tatsuya NAKAGAITO ,  Yuichi TOKITA ,  Toru MINOTE ,  Yoshikiyo TAMAI

IPC: C21D9/50 ,  B21D22/02 ,  C21D1/673 ,  C22C18/00 ,  C25D3/22 ,  C23F17/00 ,  C21D8/02

CPC classification number: C21D9/50 ,  B21D22/022 ,  B21D22/20 ,  B21D22/203 ,  B21D22/208 ,  B21D37/16 ,  C21D1/673 ,  C21D8/0205 ,  C21D8/0278 ,  C22C18/00 ,  C23F17/00 ,  C25D3/22

Abstract: A method for manufacturing a hot press formed part, includes: preparing a hot press forming object comprising a single-ply portion and a two-ply portion; heating the hot press forming object to a temperature range from an Ac3 transformation temperature of a base steel sheet of the first coated steel sheet to 1000° C.; press forming the hot press forming object to obtain a formed body, the press forming being started upon temperatures of the single-ply portion and of the two-ply portion being no higher than solidification points of Zn—Ni coating layers of the first and second coated steel sheets and no lower than an Ar3 transformation temperature of the base steel sheet of the first coated steel sheet; and quenching the formed body to thereby obtain a hot press formed part, in which the hot press forming object has a thickness ratio from 1.4 to 5.0.

公开(公告)号：US20170225215A1

公开(公告)日：2017-08-10

申请号：US15502614

申请日：2015-09-07

Applicant: JFE STEEL CORPORATION

Inventor： Tatsuya NAKAGAITO ,  Yuichi TOKITA ,  Toru MINOTE ,  Yoshikiyo TAMAI

IPC: B21D22/20 ,  C21D1/673 ,  C22C18/00 ,  C22C38/60 ,  C23F17/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/00 ,  C23C2/02 ,  C23C2/06 ,  C21D9/46 ,  C22C38/06

CPC classification number: B21D22/208 ,  B21D22/20 ,  B21D22/201 ,  B21D24/00 ,  C21D1/673 ,  C21D9/46 ,  C22C18/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/60 ,  C23C2/02 ,  C23C2/06 ,  C23C30/00 ,  C23F17/00

Abstract: A method of manufacturing a hot press-formed part by hot pressing a coated steel sheet formed with a Zn—Ni plating layer on a surface of a steel sheet includes: heating the coated steel sheet to a temperature range of Ac3 transformation temperature to 1000° C.; cooling the coated steel sheet to 550-410° C. at a cooling rate of 100° C./s or higher by squeezing the coated steel sheet with a press tool for cooling having flat surfaces configured to contact the coated steel sheet; press forming the coated steel sheet with a tool of press forming to obtain a formed body, the press forming being initiated within 5 seconds after the cooling while the temperature of the coated steel sheet is 550-400° C.; and quenching the formed body, while squeezing the formed body with the tool of press forming and holding at its press bottom dead center, to obtain a hot press-formed part.

公开(公告)号：US20150377806A1

公开(公告)日：2015-12-31

申请号：US14766682

申请日：2013-02-08

Applicant: JFE STEEL CORPORATION

Inventor： Toru MINOTE ,  Yuichi TOKITA ,  Yoshikiyo TAMAI ,  Takeshi FUJITA

IPC: G01N25/00 ,  G01L1/00 ,  G01B21/20

CPC classification number: G01N25/00 ,  B21D22/022 ,  B21D22/208 ,  G01B21/20 ,  G01L1/00 ,  G06F17/5009 ,  G06F17/5086 ,  G06F2217/80

Abstract: A method of analyzing press-forming of a press-forming material including analyzing press-forming, analyzing springback and analyzing a change in shape of the press-forming material. The analyzing press-forming may include setting an initial temperature distribution for the heated press-forming material and performing a press-forming analysis by combining temperature analysis and structural analysis to obtain shape information, temperature distribution, stress distribution, and strain distribution. The analyzing springback may occur with and without consideration of contact heat transfer between a press-forming tool and the press-forming material. The method may further include modifying the temperature distribution obtained in the analyzing springback and then re-analyzing the change in shape of the press-forming material. The analyzing the change in shape may be performed until a temperature distribution in the press-forming material is within the range of ±5° C.

Abstract translation: 一种分析压制成形材料的压制成形方法，包括分析压制成型，分析回弹和分析压制成型材料的形状变化。 分析压制成形可以包括设定加热成形材料的初始温度分布，并通过组合温度分析和结构分析进行压制成形分析，以获得形状信息，温度分布，应力分布和应变分布。 在压制成形工具和压制成形材料之间可以考虑和不考虑接触热传递而发生分析回弹。 该方法还可以包括改变在分析回弹中获得的温度分布，然后重新分析压制成形材料的形状变化。 可以进行分析形状变化，直到压制成形材料中的温度分布在±5℃的范围内

公开(公告)号：US20240320384A1

公开(公告)日：2024-09-26

申请号：US18274533

申请日：2021-11-01

Applicant: JFE STEEL CORPORATION

Inventor： Yuichi TOKITA ,  Tsuyoshi SHIOZAKI

IPC: G06F30/15 ,  B62D65/02

CPC classification number: G06F30/15 ,  B62D65/02

Abstract: An optimization analysis method for joining positions of an automotive body includes setting the whole or part of an automotive body model as an analysis object model, generating an optimization analysis model by densely setting joining candidate points to the analysis object model, setting a variable loading condition, setting a reciprocal of a predetermined target fatigue life as a target liner cumulative damage, setting improvement of stiffness of the optimization analysis model, reduction of liner cumulative damage that is a reciprocal of fatigue life of joining candidate points, and minimization of the number of joining candidate points, as optimization analysis conditions, and performing optimization analysis by applying the variable loading condition to the optimization analysis model to obtain optimal arrangement of the joining points that achieves the optimization analysis conditions.