Nippon Kokan Kabushiki Kaisha

Nkk Corporation

Kokan Mining Co., Ltd.

Irox-Nkk Co., Ltd.

Tomihiro Hara

Masaaki Yamashita

Takeshi Adaniya

Masahiro Ogawa

Tsutomu Watanabe

Shuzo Fukuda

Hiroshi Kagechika

Shunichi Sugiyama

Yoshinori Yomura

Hideyuki Yoshikoshi

Akira Tonouchi

Yutaka Ohkubo

Hiroshi Kametani

Akira Enatsu

Masaru Sagiyama

Masakazu Tsukada

Takashi Shimoma

Masaru Nabatame

Nobuaki Ikeda

Yasuhisa Tajiri

Satoshi Doi

Methods of manufacturing a composite ferrite of two or more of metal oxides prepared from a chloride solution containing ions of these metals, one of the metals being zinc. The methods comprise (a) ejecting a high temperature gas to the solution or atomizing the solution and (b) supplying the atomized gas to a combustion gas containing oxygen, to evaporate moisture from mist particles of the solution in a short period of time so that the zinc chloride in the solution is not substantially evaporated and to induce a heat decomposition or chemical reaction for the remaining metal salt particles, thereby forming a composite ferrite.

Method of manufacturing composite ferrite

An apparatus for hot dip plating on one side of a metal strip, comprising a plurality of nozzles disposed at an oblique angle to the direction of travel of the strip and having outlets which are tilted toward the edges of the strip, whereby splashing of the plating material is avoided, and occurence of plating material on the non-plated side of the strip is also avoided, and the plating is regular and without irregularity of plating or areas lacking plating material.

Apparatus of hot dip plating on one side of strip

The present invention relates to a process for the preparation of a highly anticorrosive surface-treated steel plate. This process comprises the steps of subjecting a surface of a steel plate having a plating layer of the zinc or aluminum type deposited thereon to a chromate treatment to form a chromate film, treating the steel plate with an organic composite silica solution comprising an epoxy resin in an amount exceeding a certain level as an indispensable component and a curing agent optionally incorporated therein to form an organic composite silicate film comprising colloidal silica, organic resin and silane formed on the chromate film, and heat-treating the steel plate at a specific temperature.

Process for preparation of highly anticorrosive surface-treated steel

An iron-zinc alloy electro-galvanized steel sheet having a plurality of iron-zinc alloy coatings, which comprises: at least one iron-zinc alloy coating as the lower layer, formed on the surface of a steel sheet, and at least two iron-zinc alloy coatings as the upper layer, formed on the at least one iron-zinc alloy coating as the lower layer. The ratio of iron content to the coating weight of each of the at least one iron-zinc alloy coating as the lower layer is within the range of from 1 to 15 wt. %, and the total coating weight of the at least one iron-zinc alloy coating as the lower layer is within the range of from 1 to 50 g/m.sup.2 per side of the steel sheet. The ratio of iron content to the coating weight of each of the at least two iron-zinc alloy coatings as the upper layer is over 15 wt. %, the ratio of iron content to the coating weight gradually increases from the innermost coating toward the outermost coating of the at least two iron-zinc alloy coatings as the upper layer, the difference in the ratio or iron content to the coating weight between two adjacent coatings of the at least two iron-zinc alloy coatings as the upper layer is within the range of from 1 to 15 wt. %, and the total coating weight of the at least two iron-zinc alloy coatings as the upper layer is within the range of from 1 to 40 g/m.sup.2 per side of the steel sheet. The difference in the ratio of iron content to the coating weight between the uppermost coating of the at least one iron-zinc alloy coating as the lower layer and the lowermost coating of the at least two iron-zinc alloy coatings as the upper layer is within the range of from 1 to 15 wt. %. The sum of the total coating weight of the at least one iron-zinc alloy coating as the lower layer and the total coating weight of the at least two iron-zinc alloy coatings as the upper layer is within the range of from 10 to 75 wt. % per side of the steel sheet.

Iron-zinc alloy electro-galvanized steel sheet having a plurality of

A strip horizontally travels within an electroplating apparatus while the plating solution is applied between the strip and anode, in which relative speed of the solution to the strip and/or current density are varied, whereby an outer plated layer on the strip is provided with Fe-Zn alloy of high Fe content while an inner plated layer on the strip is provided with Fe-Zn alloy of low Fe content.

Method of Fe-Zn alloy electroplating

A steel sheet utilized to prepare cans comprises an iron base sheet, a Fe--Sn alloy layer formed on the iron base sheet and containing 0.05-0.7 g/m.sup.2 of tin and 40-80 atomic % of iron, and a composite oxide film formed on the alloy layer and containing Fe, Sn, Cr and O. The composite oxide film is formed by applying a cathodic dichromate treatment to the steel sheet which has been quenched and cooled to form an oxide film on the alloy layer, the oxide film containing both of tin and iron oxides being converted to the composite oxide film.

Steel sheets for preparing welded and coated cans and method for

A multi-layer surface-treated steel plate comprises a zinc-containing plated layer, a lithium silicate film layer formed on said plated layer and an organic composite silicate film layer composed of colloidal silica and an organic resin, which is formed on the lithium silicate film layer.

Multi-layer surface-treated steel plate having zinc-containing layer

A composite coating steel sheet is disclosed which has good corrosion resistance, paintability and corrosion resistance after paint coating. The steel sheet comprises a plated base steel sheet, such as a galvanized, zinc alloy plated or aluminum plated steel sheet, and a chromate film formed on the plated base steel sheet. A composite silicate resin film is formed on the chromate film. The composite silicate film is composed of a reaction product of a colloidal silica, an organic resin and a silane compound.

Composite coating steel sheets having good corrosion resistance

A steel sheet with its surface prepared for paint coating is disclosed. The surface treated steel sheet comprises a base sheet, and an iron-zinc alloy film plated on the base sheet in an amount of at least 0.1 g/m.sup.2 and having an iron content of from 3 to 30%. A composite silicate resin film is coated on the iron-zinc alloy film in an amount of from 0.05 to 5.0 g/m.sup.2. The resin film is composed of an acrylic copolymer, an epoxy resin, a silica sol and a trialkoxysilane compound. The treated surface provides superior paintability, degrease resistance and corrosion resistance after pain coating.

Growing community of inventors

Yokohama, Japan

Tomihiro Hara