Jfe Steel Corporation

Kansai Paint Company, Ltd.

Nkk Corporation

Hisato Noro

Kaoru Sato

Norihiko Nakamura

Takeshi Suzuki

Hiroki Iwasa

Masaaki Yamashita

Yuka Miyamoto

Katsumi Yamada

Seiichi Watanabe

Kazuhiko Baba

Masao Inose

Yoichi Tobiyama

Junichi Kitagawa

Yuji Yamasaki

Masaki Tada

Akira Matsuzaki

Satoru Ando

Yoichiro Yamanaka

Masayasu Nagoshi

Takahiro Kubota

Hiroyuki Masuoka

Junichi Inagaki

Yoshihiko Yasue

Masayasu Ueno

Naoto Yoshimi

Yoshiharu Sugimoto

Yukio Kimura

Takako Yamashita

Kazuaki Kyono

Satoshi Kinoshiro

Reijiro Nishida

Shoichi Tanaka

Noriko Makiishi

Haruo Nakamichi

Wataru Tanimoto

Masahiko Tada

Masahiro Murata

Tomoharu Ishida

Hiroyasu Matsuki

Manabu Watanabe

Tomohiro Matsushima

Hisao Yasuhara

Yasuhiro Sodani

Yoshikazu Morohoshi

Shogo Tomita

Shingo Amaki

Shigeyuki Aizawa

Souki Yoshida

Okai Kazuhisa

Yoshihisa Kajima

Mitsuyoshi Sekimoto

A coated steel sheet includes a corrosion-resistant coating composed of at least one layer selected from the group consisting of a Ni layer, a Sn layer, an Fe&#x2014;Ni alloy layer, an Fe&#x2014;Sn alloy layer, and an Fe&#x2014;Ni&#x2014;Sn alloy layer disposed on at least one surface of a steel sheet, and an adhesive coating disposed on the corrosion-resistant coating, the adhesive coating containing Zr and further containing at least one metal element selected from the group consisting of Co, Fe, Ni, V, Cu, Mn, and Zn, in total, at a ratio by mass of 0.01 to 10 with respect to Zr. The coated steel sheet has excellent humid resin adhesion and corrosion resistance, in which streaky surface defects do not occur.

Coated steel sheet, method for producing the same, and resin-coated steel sheet obtained using the same

Provided are an apparatus for continuous electrolytic treatment of a steel sheet that is suitable for producing a surface-treated steel sheet and a method for producing the surface-treated steel sheet using the apparatus for continuous electrolytic treatment of a steel sheet. The apparatus includes N pairs of tabular electrodes having a length L and being arranged to respectively face two surfaces of a steel sheet. Each electrode includes n sections arranged in the longitudinal direction of the electrode and disposed on the surface of the electrode facing the steel sheet surface. Each section is constituted by a conductive portion including an electrode portion having a length Tand a nonconductive portion made by making an electrode portion having a length Tnonconductive, where n&#xd7;N&#x2267;10, 0.96&#x2267;T/(T+T)&#x2267;0.05, and 0.9&#x2267;T/L&#x2267;0.1.

Apparatus for continuous electrolytic treatment of steel sheet and method for producing surface-treated steel sheet using the same

This invention provides methods and apparatuses which can manufacture Si-containing cold rolled steel sheets exhibiting excellent chemical conversion properties even if a chemical conversion treatment solution is used at a lower temperature while minimally suppressing the generation of sludge as well as reducing running costs. The method includes steps of cold rolling a steel containing 0.5 to 3.0 mass % Si, continuously annealing the cold rolled steel sheet, pickling the surface of the continuously annealed cold rolled steel sheet, and repickling the surface of the pickled steel sheet with a non-oxidative acid. The repickling is performed such that a repickling solution is sampled continuously or periodically, an acid concentration in the sampled solution is measured, and the acid concentration in the repickling solution is regularly controlled within a prescribed concentration range.

Method and apparatus for manufacturing Si-containing cold rolled steel sheets

A method to evaluate the corrosion resistance of a can to a content includes filling the can with the content to form a specimen, setting the specimen in an apparatus capable of blocking an outside atmosphere from entering the specimen, optionally saturating the content with nitrogen gas to expel dissolved oxygen present in the content, thereafter while maintaining the temperature of the content at a constant temperature in the range of 25 to 60&#xb0; C., applying a constant potential that is more anodic than an immersion potential by 50 mV to 200 mV to the can of the specimen, and evaluating the corrosion resistance of the can to the content based on the accumulated amount of electricity generated during a time appropriately selected from 6 to 48 hours immediately after the application of the constant potential.

Method for evaluating corrosion resistance of cans to contents

A method for analyzing a metallic material includes the steps of electrolyzing a metal sample in an electrolyte; removing the electrolyzed metal sample from the electrolyte; immersing the metal sample removed from the electrolyte into a dispersive solution that is different from the electrolyte to separate at least one selected from the group consisting of a precipitate and an inclusion deposited on the metal sample; and analyzing the at least one selected from the group consisting of a precipitate and an inclusion extracted into the dispersive solution.

Method for analysis of metal inclusions in steels by partial electrolysis

The press formability of a galvanized steel sheet including an oxide film, which has a thickness of 10 nm to 100 nm, as a surface layer is nondestructively speedily evaluated. A specific method for solving problems is characterized by including the steps of irradiating X-rays to a galvanized steel sheet, dispersing a fluorescent X-ray, which is excited and emitted in the applying, with an analyzing crystal exhibiting the difference in diffraction angle between a primary oxygen K&#x3b1; x-ray and a secondary zinc L&#x3b2; x-ray of 2 degrees or more, detecting the X-ray, which is dispersed in the dispersing and which mainly contains the primary oxygen K&#x3b1; x-ray, with a detector, separating an X-ray at an energy level within the range of &#xb1;25% to &#xb1;75% relative to the reference (100%) that is the energy level of the primary oxygen K&#x3b1; x-ray from the X-ray, which is detected in the detecting and which mainly contains the primary oxygen K&#x3b1; x-ray, by adjusting the window width of a pulse-height analyzer, measuring the intensity of the X-ray separated in the separating, and evaluating the press formability of the galvanized steel sheet on the basis of the intensity of the X-ray measured in the measuring.

Method for evaluating press-formability of galvanized steel sheet

The invention is to provide a surface-treated steel sheet of good white rust resistance with no chromium in its surface treatment film, and it has realized a surface-treated steel sheet of higher-level corrosion resistance by forming a reaction layer of plating metal with a barrier layer effective for anticorrosion not in a two-layered film but in a single-layered film. The surface-treated steel sheet is fabricated by applying a surface-treating composition that contains:

Surface-treated steel sheets of good white rust resistance, and method for producing them

The method for manufacturing galvanized steel sheet has a step of adjusting the surface texture thereof by blasting solid particles against the surface thereof. The surface texture is defined by at least one parameter selected from the group of parameters consisting of mean roughness Ra on the surface of steel sheet, peak count PPI on the surface of steel sheet, and filtered centerline waviness Wca on the surface of steel sheet. The galvanized steel sheet has a surface in dimple-pattern texture.

Galvanized steel sheet, method for manufacturing the same, and method for manufacturing press-formed product

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Kanagawa, Japan

Hisato Noro