Nippon Steel Corporation

Yujiro Tatsumi

Shinji Kodama

Masanori Yasuyama

Yoshiaki Nakazawa

Toshiya Suzuki

Koichi Hamada

Kenichiro Otsuka

Yasunobu Miyazaki

Hiroki Fujimoto

Naruhiko Nomura

Yasuaki Naito

Hitoshi Sakuma

Shoko Oami

Ayaka Musha

A method of manufacturing a press-formed product includes a heating step, a transportation step, and a pressing step. At the heating step, workpieces are heated while a first workpiece Wis placed on a first group of strutsextending upward from a tray body, and a second workpiece Wis placed on a second group of strutsto be located above the first workpiece Wand overlap it. At the transportation step, the second workpiece W, while located above the first workpiece Wand overlapping it, is transported, together with the tray body, from the heating deviceto the lifting location. At the lifting location, the second workpiece Wis lifted upward by the transportation deviceand the first workpiece Wis lifted by the transportation devicebefore they are transported to their respective pressing locations.

Method of manufacturing press-formed product, and tray and hot-press manufacturing line used for manufacturing press-formed product

A welding method for obtaining a lap fillet welded joint excellent in tensile strength, without causing an increase in welding deformation, not fracturing at the weld metal when a tensile load is applied, that is, a method of overlaying at least scheduled welding locations of a first steel sheet with a tensile strength of 780 MPa or more and a second steel sheet and fillet welding an end part of the first steel sheet and a surface of the second steel sheet, characterized by providing a reinforcing part at a surface of the first steel sheet at the opposite side to the surface to be overlaid with the second steel sheet and fillet welding one end part of the reinforcing material and the surface of the first steel sheet and by fillet welding the end part of the reinforcing part, the end part of the first steel sheet, and the surface of the second steel sheet so as to be covered by the weld metal.

Fillet welding method and fillet welded joint

A fillet arc welded joint formed by fillet arc welding at least two metal members, comprising a remelted and solidified portion obtained by irradiating a laser at a weld toe portion of the fillet arc welding of at least one metal member and a region including a boundary of the heat affected zone caused by the fillet arc welding at the surface of that metal member, the remelted and solidified portion being a range from a surface of the metal member to a depth of &#xbd; or less of the thickness of that metal member, an average effective crystal grain diameter of prior austenite at a heat affected zone from a boundary of the remelted and solidified portion at the surface of the metal member to a depth of 0.1 mm in the thickness direction of the metal member being 20 &#x3bc;m or less.

Fillet arc welded joint and method for producing same

A control arm includes a pair of mounting portions provided separately from each other and a main body portion extending in a X-direction and connecting the pair of mounting portions. At a cross-section perpendicular to the X-direction at a position along the X-direction, the main body portion includes: a first V-shaped member having a first apex and opening from the first apex in a V-shape toward one side in a Y-direction, and a second V-shaped member having a second apex and opening from the second apex in a V-shape toward the other side in the Y-direction. At the cross-section, the first apex and the second apex are joined. At a cross-section perpendicular to the X-direction at the center position of the main body portion in the X-direction, an opening angle of the first V-shaped member and an opening angle of the second V-shaped member are each no more than 150&#xb0;.

Control arm

A method of production of a welded structure by butt welding two steel sheets () by laser welding () while supplying assist gas () to a back surface of a melt pool (), whereby it is possible to prevent formation of a through hole in the melt part (), characterized in that a thickness of at least one steel sheet () of the two steel sheets () is 0.6 mm or less, the assist gas () is a mixed gas () containing 10 to 50 vol % of Ogas, and, when an Oconcentration in the mixed gas () is C (vol %), a flow rate L of mixed gas () (liter/min) satisfies(liter/min)&#x2212;C(vol %)&#xd7;1 (liter/min/vol %)&#x2264;L (liter/min)&#x3c;40 (liter/min).

Production method for welded structure

Growing community of inventors

Tokyo, Japan

Yujiro Tatsumi