Kabushiki Kaisha Kobe Seiko Sho

Kobe Steel, Ltd.

Yamakawa Industrial Co.

Ichiro Kokubo

Shunichi Hashimoto

Masatoshi Iwai

Atsuo Mizuta

Hirohiko Sakai

Shigeki Kirihara

Yoshitaka Yamamoto

Kensaburo Takisawa

Zenichi Shibata

Yuuji Koyama

Takuo Hosoda

Masakatsu Hata

Jitsuo Kitazawa

Kazuhiko Kourida

Tsunahiro Yamakawa

Kazuhiro Mimura

Satoru Nito

Seiji Ban

Junkiti Kobayashi

Hiroyoshi Yamakawa

Chosei Ueda

Steel containing, on a weight percent basis, 0.01 to 0.15% of carbon, 0.05 to 0.50% of silicon, 0.20 to 1.0% of manganese, 0.01 to 0.1% of aluminum, 0.3 to 2.0% of copper, 0.1 to 2.0% of nickel, 0.015 to 0.1% of niobium and 0.0005 to 0.0050% of calcium, the balance of its composition being iron and unavoidable impurities, is heated to a temperature of 1100.degree. C. to 1250.degree. C., and hot rolled. The hot-rolled steel is coiled at a temperature of 350.degree. C. to 500.degree. C. to prepare a hot-rolled steel sheet having a tensile strength not exceeding 65 kgf/mm.sup.2. The sheet is cold worked until a working strain of at least 15% is set up. The cold-worked product is heated at a temperature of 400.degree. C. to 550.degree. C. for 0.5 to three hours to yield a part having a tensile strength of at least 80 kgf/mm.sup.2 for an automobile, particularly its automatic transmission system.

Process for manufacturing high-strength parts of an automobile

A high strength hot rolled steel sheet for wheel rims contains, by weight, from 0.05 to 0.15% of C, from 0.05 to 0.5% of Si, from 1.0 to 1.6% of Mn, from 0.01 to 0.05% of Al, from 0.005 to 0.025% of Ti and from 15 to 60 ppm of N, with the content of P limited to 0.030% or below and the content of S limited to 0.010% or below, the balance being iron and unavoidable impurities. The steel sheet optionally contains, by weight, from 0.01 to 0.06% of Nb or at least one selected from the group consisting of from 0.0005 to 0.01% of Ca and from 0.005 to 0.1% of rare earth metals.

High strength hot rolled steel sheet for wheel rims

A plate-like stock material is rolled or edged to a desired width on an edging stand of an edger. The edging stand is equipped with a pair of vertical rolls. The central axis of at least one of the vertical rolls of the edging stand is tilted within a suitable angle range toward the same direction as the advancing direction of the stock material or toward the direction opposite to the advancing direction of the stock material in a vertical plane parallel to the advancing direction of the stock material. The resulting downward bending deformation is received by a table roller.

Rolling method of plate-like stock material by edger, and continuous hot

An article of manufacture comprising a steel substrate coated with an electroplated metallic double layer with good corrosion resistance after painting and wet adhesion of paint film; said article having on the steel substrate a first layer of electroplated Zn-Ni alloy containing 7-15 wt % of Ni and on the first layer and, on said first layer, a second electroplated layer of iron or Fe-Zn alloy containing more than 60% of Fe and less than 40% of Zn.

Double-layer electroplated steel article with corrosion resistance after

A thin rolled steel plate, and method and apparatus for producing it is disclosed. The thin rolled steel plate is formed with a drum shape in cross-section with a thickness ratio of a central portion to the edge portions of at least 1.1. The rolled steel plate is rolled having a concave drum shape during the rough rolling step and/or the first half of the hot finishing rolling step so as to achieve the desired drum shape. The plate is subsequently rolled in the second half of the hot finishing rolling step and the cold finishing rolling step by concave drum shaped rollers which reduce its thickness while not altering its drum shape.

Thin rolled steel plate having unequal thickness

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Kakogawa, Japan

Ichiro Kokubo