Nippon Steel Corporation

Nippon Steel Sumitomo Metal Corporation

Sony Corporation

Kenichiro Matsumura

Kohei Tokuda

Yasuto Goto

Noriyuki Maekawa

Kiyokazu Ishizuka

Nobuyuki Shimoda

Hiroaki Uramoto

Takuya Mitsunobu

Masahiro Fuda

Hidetoshi Shindo

Akihiro Sengoku

Akinobu Kobayashi

Ikuro Yamaoka

Hirokazu Taniguchi

Hiroshi Takebayashi

Makoto Nakazawa

Satoshi Kato

Mamoru Saito

Toshiki Nonaka

Akira Takahashi

Ikuo Kikuchi

Toyomitsu Nakamura

Miwako Yoritate

Takashi Futaba

Koji Kawanishi

Fumiaki Nakamura

Yuto Fukuda

Yuuki Yasuda

Hisashi Baba

Toshiki Hattori

Kohji Yanaba

Yasuhiro Majima

Naoyuki Yamato

Yuki Yasuda

Satoshi Nippon Steel Corporation Kato

A plated steel sheet comprises a plated layer on a surface of a steel sheet, in which in the plated layer, the total amount ΣA of Sn, Bi, and In is less than 0.75%, the total amount ΣB of Ca, Y, La, and Ce is 0.03 to 0.60%, the total amount ΣC of Cr, Ti, Ni, Co, V, Nb, Cu, and Mn is 0 to 1.00%, Sn≤Si, and 20.0≤Mg/Si are satisfied, and in an X-ray diffraction pattern of a surface of the plated layer, an X-ray diffraction peak of AlZnCa, an X-ray diffraction peak of CaZn, and an X-ray diffraction peak of η'-MgZnsatisfy a predetermined relationship.

Plated steel sheet

The present invention provides a coated steel product including: a steel product; a coating layer that is coated on the surface of the steel product and that includes from 8 to 50% by mass of Mg, from 2.5 to 70.0% by mass of Al, and from 0.30 to 5.00% by mass of Ca, with the balance consisting of Zn and impurities; and an intermediate layer interposed between the steel product and the coating layer, in which the intermediate layer has a sea-island structure constituted by a sea portion composed of an Al&#x2014;Fe alloy phase, and island portions including a Zn&#x2014;Mg&#x2014;Al alloy phase having a Mg content of 8% by mass or more, and in which the sea portion composed of the Al&#x2014;Fe alloy phase has an area fraction of from 55 to 90%.

Coated steel product

A manufacturing method of a steel sheet includes: a step of performing continuous casting of molten steel having a Si content of 0.4 mass % to 3.0 mass % to obtain a slab; a step of performing hot rolling of the slab to obtain a hot-rolled steel sheet; a step of performing cold rolling of the hot-rolled steel sheet to obtain a cold-rolled steel sheet; a step of performing cold-rolled sheet annealing of the cold-rolled steel sheet; a step of performing pickling after the cold-rolled sheet annealing; a step of performing water washing after the pickling; and a step of performing drying after the water washing. A dew point is set to &#x2212;35&#xb0; C. or lower in the cold-rolled sheet annealing, an electrical conductivity of a rinse water to be used in the water washing is set to 5.0 mS/m or less, a water-washing time is set to 15 seconds or less in the water washing, and the drying is started within 60 seconds from an end of the water washing.

Manufacturing method of steel sheet

There is provided a hot-stamped body including: a steel base metal; and a metallic layer formed on a surface of the steel base metal, wherein the metallic layer includes: an interface layer that contains, in mass %, Al: 30.0 to 36.0%, has a thickness of 100 nm to 5 &#x3bc;m, and is located in an interface between the metallic layer and the steel base metal; and a principal layer that includes coexisting MgZnphases and insular FeAlphases, is located on the interface layer, and has a thickness of 3 &#x3bc;m to 40 &#x3bc;m.

Hot-stamped body

There is provided a hot-stamped body including: a steel base metal; and a metallic layer formed on a surface of the steel base metal, wherein the metallic layer includes: an interface layer that contains, in mass %, Al: 30.0 to 36.0%, has a thickness of 100 nm to 15 &#x3bc;m, and is located in an interface between the metallic layer and the steel base metal; and a principal layer that includes coexisting Zn phases and insular FeAlphases, is located on the interface layer, and has a thickness of 1 &#x3bc;m to 40 &#x3bc;m. This hot-stamped body is excellent in fatigue properties, corrosion resistance, and chipping resistance.

Provided is a surface treated steel sheet for a fuel tank, the surface treated steel sheet including: a Zn plated layer or a Zn&#x2014;Ni alloy plated layer which is formed on at least a surface of the steel sheet to be an inner surface of the fuel tank; and a chromate-free chemical conversion coating layer containing a water-and-oil repellent, the chromate-free chemical conversion coating layer being placed over the Zn plated layer or the Zn&#x2014;Ni alloy plated layer on the surface to be the inner surface of the fuel tank. A water contact angle on a surface of the chromate-free chemical conversion coating layer is more than or equal to 70 degrees and an n-hexadecane contact angle on the surface of the chromate-free chemical conversion coating layer is more than or equal to 30 degrees and less than or equal to 70 degrees.

Surface treated steel sheet for fuel tank

A steel sheet for a fuel tank according to the present invention includes: a Zn&#x2014;Ni alloy plated layer placed on one surface or each of both surfaces of a base metal; and a chromate-free chemical conversion coating film which is placed over the Zn&#x2014;Ni alloy plated layer. The Zn&#x2014;Ni alloy plated layer has a crack starting from an interface with the chromate-free chemical conversion coating film and reaching an interface with the steel sheet, the chromate-free chemical conversion coating film consists of an organosilicon compound consisting of a condensation polymer of a silane coupling agent, a phosphoric acid compound and/or a phosphonic acid compound, a vanadium compound, and a titanium compound and/or a zirconium compound, and a concentration of a total of amounts in terms of metal, per surface, of the phosphoric acid compound and/or the phosphonic acid compound+the vanadium compound+the titanium compound and/or the zirconium compound, is 5 mass % to 20 mass %.

Steel sheet for a fuel tank

A steel sheet for a fuel tank includes: a Zn&#x2014;Ni alloy plated layer which is placed on one surface or each of both surfaces of a base metal and formed on at least one surface; and an inorganic chromate-free chemical conversion coating film which is placed over the Zn&#x2014;Ni alloy plated layer. The Zn&#x2014;Ni alloy plated layer has a crack starting from an interface between the Zn&#x2014;Ni alloy plated layer and the inorganic chromate-free chemical conversion coating film and reaching an interface between the Zn&#x2014;Ni alloy plated layer and the steel sheet, and a water contact angle on a surface of the inorganic chromate-free chemical conversion coating film is more than or equal to 50 degrees.

The invention provides a coated steel including a steel, a coated metal layer coated on a surface of the steel, and an interfacial alloy layer formed at the boundary between the steel and the coated metal layer, in which the coated metal layer has a predetermined composition and structure, and in which the thickness of the coated metal layer is 0.1 &#x3bc;m or more, and the thickness of the interfacial alloy layer is 500 nm or less.

Coated steel

A plated steel sheet including an alloy plating layer formed on a surface of the steel sheet consisting of, in mass %, Cr: 5 to 91%, Fe: 0.5 to 10%, and the balance: Ni and unavoidable impurities, the Ni concentration gradually decreases from an outermost surface of the alloy plating layer to a side of the steel sheet, Ni/Cr&#x3e;1 in an area extending 300 nm or more from the outermost surface of the alloy plating layer, the Fe concentration in the alloy plating layer gradually decreases from the side of the steel sheet to the outermost surface, the Fe concentration in the outermost surface 0.5% or less, the total thickness of an alloy layer formed in the alloy plating layer and containing Cr and Fe is 500 to 2000 nm, and the total amount of the alloy plating layer deposited to the steel sheet is 4.5 to 55.5 g/m.

Plated steel sheet and method producing same

A Mg-containing Zn alloy coated steel including a steel and a metallic coating layer placed on a surface of the steel, in which the metallic coating layer is a layered structure of plural flat-form metal particles having a particle diameter of from 5 to 100 &#x3bc;m, and a thickness of from 0.5 to 30 &#x3bc;m, the composition of the metal particles include Zn from 11 to 80 mass %, Al from 3 to 80 mass %, Mg from 8 to 45 mass %, and Ca from 1 to 5 mass %, and the Zn, Al, and Mg content satisfy Zn+Al&#x3e;Mg, and in which the metal particles include a quasicrystalline phase, an MgZnphase, and optionally a balance structure.

Mg-containing Zn alloy coated steel

The present invention provides hot dip galvanized high strength steel sheet excellent in plating adhesion and hole expandability and a method of production of the same, that is, hot dip galvanization steel sheet excellent in plating adhesion and hole expandability containing, by mass %, C: 0.08 to 0.35%, Si: 1.0% or less, Mn: 0.8 to 3.5%, P: 0.03% or less, S: 0.03% or less, Al: 0.25 to 1.8%, Mo: 0.05 to 0.35%, and N: 0.010% or less and having a balance of Fe and unavoidable impurities, said hot dip galvanized high strength steel characterized in that the steel sheet has a metal structure having ferrite, bainite, by area percent, 0.5% to 10% of tempered martensite, and, by volume percent, 5% or more of residual austenite, and a method of production comprising annealing by a continuous annealing process at 680 to 930&#xb0; C. in temperature, then cooling to the martensite transformation point or less, then hot dip galvanizing the steel during which heating the steel to 250 to 600&#xb0; C., then hot dip galvanizing it.

Hot dip galvanized high strength steel sheet excellent in plating adhesion and hole expandability and method of production of same

A method using a continuous annealing furnace where a cooling method of a cooling zone including part or all of the temperature range of the steel sheet of 600 to 250&#xb0; C. following the heating for recrystallization is one or more of gas cooling, effusion cooling, and cooling pipe cooling, or a joint cold rolled steel sheet/hot dip galvanized steel sheet facility having such a continuous annealing furnace, to continuously anneal cold rolled steel sheet to produce high strength cold rolled steel sheet, characterized by exposing the steel sheet surface to an iron-oxidizing atmosphere in the steel sheet temperature range to make the surface oxidize, pickling the sheet at the outlet side of the annealing furnace, then iron- or Ni-plating the sheet to 1 to 50 mg/m.

Method of production and production facility of high strength cold rolled steel sheet excellent in chemical convertibility

A display apparatus for video signals has improved operability. The display apparatus includes a tuner which receives a video signal, an external input unit into which a video signal is input from the outside, a display processor operable to select one of the video signal received by the tuner or that obtained from the external input unit as a main video and to perform display processing on the main video, a display unit operable to display the video signals processed in the display processor, an operation unit and a controller operable to combine an operation guidance video with the main video to form a combined display based on a predetermined operation in the operation unit, and to display the combined display, wherein the combined display is displayed in different display modes depending on which video signal forms the main video. The operation unit may be in the form of a touch panel. Furthermore, when a specific button is operated, a display to select a function is performed.

Display apparatus having multiple source-dependent display modes

A process for producing a Zn--Cr alloy-electroplated steel plate, comprising immersing a steel plate in an acidic bath containing Zn.sup.+2 ions and Cr.sup.+3 ions and subjecting the steel plate to electroplating in the bath, wherein 0.01 g/-20 g/l of an additive comprising one or more members selected from the group consisting of polyethyleneoxyphenol derivatives with a sulfonic group (--SO.sub.3 H), sulfate group (--SO.sub.4 H), amino group (--NH.sub.2), carboxyl group (--COOH), nitro group (--NO.sub.2) or halogen (--F, --Cl, --Br or --I) as a substituent in the benzene ring, alkyl sulfonic acid compounds and polyethyleneoxyalkyl sulfonic acid compounds are added to the bath. The plating process makes it possible to produce Zn--Cr alloy-properties steel plates at a low cost without the additives having any adverse effect on the properties of the plating.

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Tokyo, Japan

Kenichiro Matsumura