公开(公告)号：US20160121384A1

公开(公告)日：2016-05-05

申请号：US14896229

申请日：2014-04-14

Applicant: JFE STEEL CORPORATION

Inventor： Satoshi SUMIKAWA ,  Akinobu ISHIWATARI ,  Jiro HIRAMOTO

IPC: B21D22/02

CPC classification number: B21D22/02 ,  B21D22/10 ,  B21D22/26

Abstract: A method of press forming includes: forming a trench-shaped portion into a product shape with a die and a punch until reaching a first bottom dead center, and forms at least one of: a flange portion subject to shrink flange deformation such that a linear length of the flange portion subject to the shrink flange deformation in a longitudinal direction is shorter than a linear length of a flange portion in the product shape; and a flange portion subject to stretch flange deformation such that a linear length of the flange portion subject to the stretch flange deformation in the longitudinal direction is longer than the linear length of the flange portion in the product shape; and forming the formed flange portion into the product shape with the die and a flange forming die until reaching a second bottom dead center.

Abstract translation: 一种压制成形方法包括：通过模具和冲头将沟槽状部分形成为产品形状，直到达到第一下死点，并且形成以下中的至少一个：凸缘部分经受收缩凸缘变形，使得线性 受到收缩凸缘长度方向变形的凸缘部的长度比产品形状中的凸缘部的直线长度短; 以及凸缘部，其经受拉伸凸缘变形，使得在纵向方向上受拉伸凸缘变形的凸缘部分的线性长度比产品形状中的凸缘部分的线性长度长; 并且将所形成的凸缘部分形成为具有模具和凸缘成形模具的产品形状，直到达到第二下死点。

公开(公告)号：US20180021831A1

公开(公告)日：2018-01-25

申请号：US15552615

申请日：2016-01-27

Applicant: JFE STEEL CORPORATION

Inventor： Ryo AGEBA ,  Akinobu ISHIWATARI ,  Jiro HIRAMOTO

IPC: B21D19/08 ,  B21D22/20

CPC classification number: B21D19/08 ,  B21D22/20

Abstract: A press forming method for forming a press-formed product having no flange portion from a blank by performing a crash forming process while using a die and a punch, the press-formed product including at least a top portion and a side wall portion continued from the top portion via a connecting portion and being structured so that either all or a part of the side wall portion curves toward an outside of the press-formed product to form a convex shape in a planar view, the press forming method including forming the side wall portion while keeping a tip end portion of the blank in continuous contact with a side wall forming portion of the die and causing the die to impose no restraint on any part other than the tip end portion of the blank.

公开(公告)号：US20150294043A1

公开(公告)日：2015-10-15

申请号：US14436236

申请日：2013-10-10

Applicant: JFE STEEL CORPORATION

Inventor： Osamu SONOBE ,  Akinobu ISHIWATARI ,  Masaki URABE ,  Hirotaka KANO ,  Jiro HIRAMOTO

IPC: G06F17/50 ,  G06F17/10 ,  G01L5/00

CPC classification number: G06F17/5009 ,  B21D19/00 ,  B21D22/02 ,  B21D53/88 ,  G01L5/00 ,  G01M99/007 ,  G01N3/28 ,  G01N2203/0075 ,  G01N2203/0254 ,  G01N2203/027 ,  G06F17/10

Abstract: A method for specifying stretch flange limit strain includes specifying stretch flange limit strain so as to satisfy a relation in the following formula by using: strain gradient in an inward direction directed from an end portion of a metal sheet at a time a press load is applied; and strain gradient in a sheet thickness direction of the metal sheet intersecting the loading direction: εθlim=A[a·Δεθ/Δr+b·Δεθ/Δt]+c where εθlim represents the stretch flange limit strain (tangential direction of the sheet edge), Δεθ/Δr represents the strain gradient in the inward direction, Δεθ/Δt represents the strain gradient in the sheet thickness direction, A, a, and b represent influence coefficients, and c represents the limit strain at a time the strain gradient is zero.

Abstract translation: 用于规定拉伸凸缘极限应变的方法包括：通过使用：在施加压力载荷时从金属板的端部指向的向内方向上的应变梯度来指定拉伸凸缘极限应变以满足下式的关系： ; 和与加载方向相交的金属板的板厚度方向的应变梯度：＆amp;＆amp;＆nbsp;＆nbsp;＆nbsp;＆nbsp;＆Dgr;＆rdquo;＆Dgr;＆ ] + c其中＆egr;＆thetas; lim表示拉伸法兰极限应变（片材边缘的切线方向），＆Dgr;＆Egr＆amp;＆Thetas; /＆Dgr; r表示向内方向的应变梯度，＆Dgr; ＆Dgr; t表示板厚方向的应变梯度，A，a和b表示影响系数，c表示应变梯度为零时的极限应变。