Kobe Steel, Ltd.

Daido Kogyo Co., Ltd.

Tsunetake Tsuyoshi

Narikazu Hashimoto

Shinya Morita

Hideki Ishitobi

Takahiro Shikama

Shingo Shimoaka

Hiroyuki Kajiwara

Toru Hashimura

Satoshi Nimura

Tomomichi Ohtani

Kenji Nakaya

Kei Chino

Koji Tabata

To compensate for a decrease in reaction force of a bumper reinforcement, which is made of an aluminum alloy extrusion having two end portions subjected to bend forming and crushed portions on the respective end portions, against an impact load in end impact involved in crushing, and compensate for a decrease in energy absorption amount of the bumper reinforcement. Assuming a space between two flanges includes a first region from a center line of the thickness between the flanges to an outer flange and a second region from the center line to an inner flange in a cross section of the crushed portion perpendicular to an extrusion direction, area of the webs located in one (for example, the first region) of the two regions is larger than area of the webs located in the other region (for example, the second region).

Bumper reinforcement for automobile

A door beam including an aluminum alloy extrusion extended in a longitudinal direction and having a pair of webs and a pair of flanges to be positioned on an inside and an outside in a vehicle width direction. The pair of webs connect the pair of flanges at joint portions of each of the pair of webs such that the pair of webs and the pair of flanges form a closed cross section in a direction perpendicular to the longitudinal direction, and each of the pair of webs has a welded portion in a vicinity of a neutral axis passing through a centroid of the closed cross section and parallel to the pair of flanges.

Door beam

A door beam including an inner flange extending in a longitudinal direction, an outer flange extending in the longitudinal direction and facing the inner flange at a distance from the inner flange, and-a pair of webs connecting the inner flange and the outer flange. The inner flange has an end portion in the longitudinal direction which is made closer to an end portion of the outer flange such that the distance between the inner and outer flanges at the end portions is shorter than the distance at other portions of the inner and outer flanges.

Door beam, door beam attachment structure, and method for manufacturing door beam

An aluminum alloy member resistant to cracking and having high strengths and excellent stress corrosion cracking resistance is manufactured by crushing a 7xxx aluminum alloy extrudate. Specifically, a 7xxx aluminum alloy extrudate containing Zn of 3.0-8.0%, Mg of 0.4-2.5%, Cu of 0.05-2.0%, and Ti of 0.005-0.2%, in mass percent, and prepared through press quenching is subjected to a reversion treatment, to crushing within 72 hours after the reversion treatment, and then to aging. The reversion treatment includes heating at a temperature rise rate of 0.4&#xb0; C./second or more, holding in a temperature range of 200-550&#xb0; C. for longer than 0 second, and cooling at a rate of 0.5&#xb0; C./second or more. The ratio of the tensile residual stress &#x3c3;to the 0.2% yield stress &#x3c3;after aging and the total content X of Mg and Zn satisfy a condition specified by Expression (1):&#x2264;&#x2212;0.1+1.4&#x2003;&#x2003;(1).

7xxx series aluminum alloy member excellent in stress corrosion cracking resistance and method for manufacturing the same

An aluminum alloy member resistant to cracking and having high strengths and excellent stress corrosion cracking resistance is manufactured by crushing a 7xxx aluminum alloy extrudate. Specifically, a 7xxx aluminum alloy extrudate containing Zn of 3.0-8.0%, Mg of 0.4-2.5%, Cu of 0.05-2.0%, and Ti of 0.005-0.2%, in mass percent, and prepared through press quenching is subjected to a reversion treatment, to crushing within 72 hours after the reversion treatment, and then to aging. The reversion treatment includes heating at a temperature use rate of 0.4&#xb0; C./second or more, holding in a temperature range of 200-550&#xb0; C. for longer than 0 second, and cooling at a rate of 0.5&#xb0; C./second or more. The ratio of the tensile residual stress &#x3c3;to the 0.2% yield stress &#x3c3;after aging and the total content X of Mg and Zn satisfy a condition specified by Expression (1):&#x2264;&#x2212;0.1+1.4&#x2003;&#x2003;(1).

The present invention relates to a structure for mounting a hook bracket formed of an aluminum alloy extrusion to a bumper reinforce having a hollow cross-section, and further reduces the weight of the hook bracket and the weight of the mount structure without deteriorating towing performance. The hook bracket has a cut that is formed in an extrusion cross-section (a cross-section perpendicular to the direction of extrusion) and extended from the rear end of a shaft portion into the hollow in the bumper reinforce. Further, an internally threaded hole is formed. The shaft portion of the hook bracket is penetrated through a hole formed in front and rear walls of the bumper reinforce and fillet-welded to the front and rear walls. The shaft portion is not fillet-welded to the rear wall at a position where the cut is formed.

Structure for mounting hook bracket to bumper reinforce and bumper structure

A bumper reinforcement is formed of a 7000 series aluminum alloy hollow extrusion and has crushed end portions. A portion of the end portions is heated to a temperature of 400&#xb0; C. or more for reversion treatment, the heated portion is subjected to cold crushing, and then the whole bumper reinforcement is subjected to age hardening. Because of the age hardening, the heated portion has higher Vickers hardness than non-heated portions by Hv 10 or more. This compensates for a decrease in reaction force in a collision of an end portion resulting from a decrease in the section modulus of the crushed portion and thereby suppresses a decrease in energy absorption.

Bumper reinforcement and method for manufacturing the same

There is provided a bumper beam that is formed of a 7000 series aluminum alloy hollow extrusion, has a crushed longitudinal portion, and locally has a low-hardness region in a bumper stay joint section. A portion (portion to be heated) of end portions of the bumper beam formed of a tempered member of a heat-treatable aluminum alloy extrusion is subjected to reversion treatment, thereby forming a heat-affected zone in a bumper stay joint section. An end region (portion to be crushed) of the heated portion is subjected to cold crushing, and then the whole bumper beam is subjected to age hardening. The heated portion and a non-heat-affected zone are hardened through the age hardening, thereby forming a low-hardness region that overlaps the joint section in a portion of the heat-affected zone.

Bumper structure and method for manufacturing bumper beam

A bumper reinforcement includes a tubular body including a front wall that serves as an impact surface and a rear wall on a vehicle body side, the tubular body extending in a vehicle width direction and having a hollow cross section; and a tow hook attachment structure for allowing a tow hook to be removably attached thereto. The tow hook attachment structure includes a pair of cylindrical protrusions respectively integrally formed with the front and rear walls of the tubular body by shaping parts of the walls, the cylindrical protrusions being disposed at predetermined positions on the front and rear walls in the vehicle width direction so as to face each other and so as to protrude inward into the hollow cross section, and at least one of the pair of protrusions includes a threaded portion for allowing a threaded portion of the tow hook to be screwed thereinto.

Bumper reinforcement and method of manufacturing the same

An anti-collision component consisting of a metal hollow profile for automobiles includes a collision side flange, a body side flange, and a web connected to the flanges. The hollow profile has a longitudinal end at which a cross-sectional configuration is deformed by swaging to reduce a dimension between the flanges. The following relations are established:&#x2267;() where tis a wall thickness of the web at the end, Tis a wall thickness of the web at a portion where the cross-sectional configuration is not deformed, and Ris an inside corner radius of a corner formed of the web and each flange at the portion.

Anti-collision component

A battery frame includes an outer frame () which has a generally rectangular shape in planar view and a lower plate () which is joined to the lower surface of the outer frame and made from an aluminum alloy. The outer frame () has a pair of frame members () which have an identical shape and are respectively made of aluminum alloy hollow extruded material bent at 90&#xb0; at two portions in the longitudinal direction and joined to each other so that the ends () of one frame member () face the ends () of the other frame member ().

Battery frame structure for automobile

The bumper stay includes a cylindrical shaft member fit in to a hole of a bumper reinforce, a cylindrical reinforcing member fit in to the outer periphery of the shaft member in the rear side of the bumper reinforce, and a mounting flange member fit in to the outer periphery of the shaft member in its rear end. The shaft member is enlarged by electromagnetic forming and is tightly adhered to the inner peripheral surface of the hole formed in the bumper reinforce, the inner peripheral surface of the reinforcing member, and the inner peripheral surface of the hole flange formed in the mounting flange member, thereby these are joined with each other. Thin aluminum alloy extruded material can be used for the shaft member. With such configuration, when a bumper stay is fit in to the holes formed in the front and rear walls of the bumper reinforce and the bumper stay is enlarged by electromagnetic forming to join with the bumper reinforce, joining of the both can be firmly performed and sufficient strength and energy absorption quantity can be secured.

Growing community of inventors

Shimonoseki, Japan

Tsunetake Tsuyoshi