Kobe Steel, Ltd.

Voestalpine Stahl Gmbh

Kabushiki Kaisha Kobe Seiko Sho

Junya Naitou

Shushi Ikeda

Keisuke Okita

Toshio Murakami

Toru Hashimura

Kenichi Watanabe

Yasuhiro Maeda

Jiro Iwaya

Takayuki Kimura

Kazuki Sakamoto

Yasuhiro Hayashida

Kensuke Funada

Shinji Sato

Hideo Hata

Andreas Pichler

Thomas Kurz

Ryohei Yukishige

Haruyuki Konishi

Hideto Katsuma

Naoto Takahashi

Shota Chinzei

Disclosed is a joining method of members, which includes the steps of: preparing a first member in which a first hole portion having a polygonal cross-sectional shape is formed, and a second member having a hollow shape, wherein the second member has a cross-sectional shape corresponding to the polygonal cross-sectional shape of the first hole portion, the second member including a plurality of straight line portions extending linearly and corner portions positioned between the adjacent two straight line portions in the cross-sectional shape; inserting the second member into the first hole portion of the first member; and caulking and joining the second member to the first member by enlarging and deforming the corner portions.

Joining method and joint structure of members

In a method for joining bumper members, a bumper reinforcement including a rear inclined wall provided with a hole, and a bumper stay in a hollow shape are prepared. The method for joining bumper members includes the steps of: inserting the bumper stay through the hole of the bumper reinforcement to pass through the rear inclined wall; inserting rubber into the bumper stay; and compressing the rubber in a direction of an axis L of the bumper stay to expand the rubber outward from inside to expand and deform at least a portion of the bumper stay inserted into the hole, thereby joining the bumper stay to the rear inclined wall by press-fitting.

Method for joining bumper members and bumper structure

A joining method for members includes: providing a steel component 10 including insertion holes 14and 15, an aluminum pipe 20 having a hollow shape, and a support component 30; inserting the aluminum pipe 20 into the insertion holes 14and 15of the steel component 10; and enlarging the aluminum pipe 20 through deformation and joining the aluminum pipe 20 to the steel component 10 by press-fitting. The press-fit joining is performed while at least part of the support component 30 is disposed in a press-fitting region.

Joining method for members

A steel sheet for hot pressing includes in a chemical composition, in percent by mass, C of 0.1% to 0.4%, Si of greater than 0% to 2.0%, Mn of 0.5% to 3.0%, P of greater than 0% to 0.015%, S of greater than 0% to 0.01%, B of 0.0003% to 0.01%, N of greater than 0% to 0.05%, Al in a content of 2&#xd7;[N]% to 0.3% at a Si content of greater than 0.5% to 2.0%; or Al in a content of (0.20+2&#xd7;[N]&#x2212;0.40&#xd7;[Si]N)% to 0.3% at a Si content of 0% to 0.5%, where [N] and [Si] are contents of N and Si, respectively, in mass percent, with the remainder being iron and inevitable impurities, where contents of Ti, Zr, Hf, and Ta, of the inevitable impurities, are each controlled to 0.005% or lower. The steel sheet includes nitride-based inclusions with an equivalent circle diameter of 1 &#x3bc;m or more in a number density of 0.10 per square millimeter.

Steel sheet for hot pressing and hot pressed article using the same

The joining method for members according to the present invention includes: providing an aluminum component including an insertion hole provided with a rib in at least part of an edge part, and a hollow steel pipe; inserting the steel pipe into the insertion hole of the aluminum component; and expanding and deforming the steel pipe to join the steel pipe to the aluminum component by press-fitting.

Structure including joint structure of dissimilar materials comprises a roof panel and a skeletal body. The roof panel has a bent portion at its end and is a panel member made of an aluminum alloy. The skeletal body has a support portion for supporting the first member and is made of steel. The roof panel and the skeletal body are joined by continuous welding of a vicinity of an apex of the bent portion of the roof panel and the support portion of the skeletal body, a reinforcing plate is joined to the roof panel at least partially along the joining portion with the skeletal body.

Structure and structure member including joint structure of dissimilar materials

A vehicle front structure includes a front side member extending in a vehicle front-rear direction in a front portion of a vehicle body, an upper side member disposed above the front side member in a vehicle and extending in the vehicle front-rear direction, and a suspension tower joined to the front side member and the upper side member. The suspension tower is made of aluminum alloy integrally formed by press working. The vehicle front structure is capable of being reduced in weight and being more easily manufactured without introducing new equipment.

Vehicle front structure and method for manufacturing same

A manufacturing method of a press-formed article includes arranging a member to be pressed between first and second dies, and relatively moving the first and second dies so as to approach each other, thereby press forming to a portion to be pressed so that a height of the portion to be pressed decreases. In the press forming step, while first bent portions in a pair each bent in a protruded shape toward the second die on the portion to be pressed are held by groove-shaped holding portions in a pair separated from each other on the second die, a second bent portion bent in a protruded shape from a position between the first bent portions toward the first die on the portion to be pressed is pressed and deformed by a pressing portion of the first die.

Manufacturing method of press-formed article, press-formed article, and press forming apparatus

In the present invention, a press-formed product is manufactured by heating a steel sheet for hot pressing use to a temperature of 900&#xb0; C. or above and 1,100&#xb0; C. or below, the steel sheet for hot pressing use having a predetermined chemical component composition, some of Ti-containing precipitates contained in the steel sheet, each of which having an equivalent circle diameter of 30 nm or less, having an average equivalent circle diameter of 6 nm or less, and the precipitated Ti amount and the total Ti amount in the steel fulfilling the relationship represented by formula (1) shown below, thereafter starting press-forming, and holding at the bottom dead point and cooling to a temperature lower than the martensite transformation starting temperature Ms while securing the average cooling rate of 20&#xb0; C./s or more within a tool.Precipitated Ti amount(mass %)&#x2212;3.4[N]&#x3c;0.5&#xd7;[total Ti amount (mass %)&#x2212;3.4[N]]&#x2003;&#x2003;(1)(In the formula (1), [N] represents the content (mass %) of N in the steel.).

Method for manufacturing press-formed product and press-formed product

A manufacturing method of press-formed article according to the present invention includes a step of placing a flat plate member between a first die and a second die, and a step of causing a first press portion and a second press portion approach each other, thereby pressing the flat plate member. In the step of placing, the flat plate member is placed so that a first main surface and a second main surface align with a vertical direction. In the step of pressing, the flat plate member is vertically pressed by causing the first press portion and the second press portion to approach each other in the vertical direction, and a thick portion is formed on the flat plate member by causing a part of a material of the flat plate member in the vertical direction to flow into a thickened portion-forming section formed on a first opposing surface.

Manufacturing method of press-formed article and press forming apparatus

A hot-press formed product can be achieved which has regions corresponding to a shock resistant portion and an energy absorption portion within a single formed product without applying a welding method and achieves the balance of high strength and elongation with a high level according to each region by means of having a first forming region exhibiting a metal structure containing martensite: 80-97 area % and retained austenite: 3-20 area % respectively, the remaining structure being 5 area % or less, and a second forming region exhibiting a metal structure containing annealed martensite or annealed bainite: 30-97 area %, martensite as quenched: 0-67 area %, and retained austenite: 3-20 area %.

Hot-press formed product and method for manufacturing same

Provided is a hot-press molded article that can achieve a high level of balance between high strength and extension by region and has a region corresponding to an energy absorption site and a shock resistant site within a single molded article without applying a welding method by means of having first region having a metal structure containing both 80-97 area % of martensite and 3-20 area % of residual austenite, the remaining structure comprising no more than 5 area %, and a second region having a metal structure comprising 30-80 area % of ferrite, less than 30 area % (exclusive of 0 area %) of bainitic ferrite, no greater than 30 area % (exclusive of 0 area %) of martensite, and 3-20 area % of residual austenite.

There is provided a hot press-formed product, including a thin steel sheet formed by a hot press-forming method, and having a metallic structure that contains bainitic ferrite at 70% to 97% by area, martensite at 27% by area or lower, and retained austenite at 3% to 20% by area, the remainder structure of which is at 5% by area or lower, whereby balance between strength and elongation can be controlled in a proper range and high ductility can be achieved.

Hot press-formed product and process for producing same

There is provided a hot press-formed product, including a thin steel sheet formed by a hot press-forming method, and having a metallic structure that contains retained austenite at 3% to 20% by volume, whereby balance between strength and elongation can be controlled in a proper range and high ductility can be achieved.

Process for producing hot press-formed product

Provided is a press-forming product manufacturing method of manufacturing a forming product having satisfactory formability for a drawing process by press-forming a metal sheet using a press-forming tool with high productivity, including: heating the metal sheet to a transformation temperature Acor more; cooling the metal sheet to 600&#xb0; C. or lower; forming the metal sheet by a forming tool; ending the forming process at a martensite transformation start temperature Ms or more; taking out the metal sheet from the forming tool; and cooling the metal sheet.

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Kobe, Japan

Junya Naitou