Nippon Steel Corporation

Nippon Steel Sumitomo Metal Corporation

Nittetsu Plant Designing Corporation

Shin-etsu Quartz Products Co., Ltd.

Heraeus Quarzglas Gmbh

Norikazu Fujii

Yoshiyuki Ushigami

Hiroyasu Fujii

Osamu Tanaka

Tomoji Kumano

Shuichi Nakamura

Kenichi Murakami

Norihiro Yamamoto

Yuji Kubo

Masayoshi Tanaka

Noriko Yamada

Kazutaka Higashine

Kazufumi Hanzawa

Chikara Kaido

Satoshi Arai

Kazutoshi Takeda

Fumiaki Takahashi

Koji Yamasaki

Hideyuki Hamamura

Takeshi Kimura

Hisashi Mogi

Kyoichi Inaki

Nobusato Morishige

Kazumi Mizukami

Masato Mizokami

Maremizu Ishibashi

Kikuji Hirose

Hideyuki Kobayashi

Eiichi Shinomiya

Eisuke Minematsu

Chie Hama

Hiroyuki Kimura

Masahide Urago

Makoto Saito

Isao Iwanaga

Akiyoshi Tsuchida

Hideki Tsuchida

Kimikazu Taniyama

Yoshifumi Ohata

Hitoshi Yokouchi

Masahide Uragoh

Provided is a silica glass disc in which the deformation amount thereof in heat treatment is minimized, and the surface area of a silica glass surface can be increased. There is provided a silica glass disc, including a dimple forming area in which a large number of dimples are formed on at least one of a front surface or a back surface of a silica glass body, and the dimples in the dimple forming area are regularly formed. It is preferred that the dimples be formed by a laser.

Silica glass disc having dimples formed thereon

A method for manufacturing a grain-oriented electrical steel sheet includes: a silicon steel material production process of producing a silicon steel material; a hot rolling process of obtaining a hot rolled sheet by subjecting the silicon steel material to hot rolling; a cold rolling process of obtaining a steel sheet of a final sheet thickness by subjecting the hot rolled sheet to a single cold rolling process or multiple cold rolling processes having intermediate annealing performed between the cold rolling processes; a decarburization annealing process of subjecting the steel sheet to decarburization annealing; and a final annealing process of applying an annealing separator containing alumina as a main component to the steel sheet and subjecting the steel sheet to final annealing.

Method for manufacturing grain-oriented electrical steel sheet

A grain-oriented electrical steel sheet includes: a base steel sheet; a primary film formed on a surface of the base steel sheet; and a tension insulation coating formed on a surface of the primary film, in which a magnetic domain control is performed by irradiating the tension insulation coating with a laser from above. When a strip-like sample having a length of 300 mm in a direction parallel to a rolling direction of the grain-oriented electrical steel sheet and a length of 60 mm in a direction parallel to a transverse direction is extracted from the grain-oriented electrical steel sheet, a range from a surface of the tension insulation coating to a depth position of 5 &#x3bc;m toward the base steel sheet side from an interface between the base steel sheet and the primary film is removed by pickling at least one surface of the sample, and a warpage amount of the sample is thereafter measured, the warpage amount satisfies predetermined conditions.

Grain-oriented electrical steel sheet causing low core loss and low magnetostriction

A grain-oriented electrical steel sheet being a grain-oriented electrical steel sheet containing Si of 0.8 mass % to 7 mass %, Mn of 0.05 mass % to 1 mass %, B of 0.0005 mass % to 0.0080 mass %, each content of Al, C, N, S, and Se of 0.005 mass % or less, and a balance being composed of Fe and inevitable impurities and having a glass coating film made of composite oxide mainly composed of forsterite on the steel sheet surface, in which when glow discharge optical emission spectrometry (GDS) to the surface of a secondary coating film formed on the surface of the glass coating film under a predetermined condition is performed, a peak, of B, in emission intensity having a peak position in emission intensity different from a peak position, of Mg, in emission intensity is obtained and the peak position, of B, in emission intensity from the steel sheet surface is deeper than the peak position, of Mg, in emission intensity.

Grain-oriented electrical steel sheet and manufacturing method thereof

In a method of manufacturing a grain-oriented electrical steel sheet including a nitriding treatment (step S) and adopting so-called 'low-temperature slab heating', the finish temperature of finish rolling in hot rolling (step S) is set to 950&#xb0; C. or below, the cooling is started within 2 seconds after completion of the finish rolling, and a steel strip is coiled at 700&#xb0; C. or below. The cooling rate over the duration from the end of finish rolling to the start of coiling is set to 10&#xb0; C./sec or above. In annealing (step S) of the hot-rolled steel strip, the heating rate in the temperature range from 800&#xb0; C. to 1000&#xb0; C. is set to 5&#xb0; C./sec or above.

Method of manufacturing grain-oriented electrical steel sheet

A nitriding treatment (Step S) in which an N content of a decarburization-annealed steel strip is increased is performed between start of a decarburization annealing (Step S) and occurrence of secondary recrystallization in a finish annealing (Step S). In hot rolling (Step S), a silicon steel material is held in a temperature range between 1000&#xb0; C. and 800&#xb0; C. for 300 seconds or longer, and then finish rolling is performed.

Manufacturing method of grain-oriented magnetic steel sheet

A silicon steel material is heated in a predetermined temperature range according to contents of B, N, Mn, S, and Se (step S), and is subjected to hot rolling (step S). Further, a finish temperature Tf of finish rolling in the hot rolling is performed in a predetermined temperature range according to the content of B. Through these treatments, a certain amount of BN is made to precipitate compositely on MnS and/or MnSe.

Manufacturing method of grain-oriented electrical steel sheet

In a production of grain-oriented electrical steel sheet that is heated at a temperature of not higher than 1350&#xb0; C., (a) the hot-rolled sheet is heated to a prescribed temperature of 1000&#xb0; C. to 1150&#xb0; C., and after recrystallization is annealed for a required time at a lower temperature of 850&#xb0; C. to 1100&#xb0; C., or (b) in the hot-rolled sheet annealing process decarburization is conducted to adjust the difference in the amount of carbon before and after decarburization to 0.002 to 0.02 mass %. In the temperature elevation process used in the decarburization annealing of the steel sheet, heating is conducted in the temperature range of 550&#xb0; C. to 720&#xb0; C. at a heating rate of at least 40&#xb0; C./s, preferably 75 to 125&#xb0; C./s, utilizing induction heating for the rapid heating used in the temperature elevation process in decarburization annealing.

Method of production of grain-oriented electrical steel sheet having a high magnetic flux density

The present invention provides a method of production of grain-oriented electrical steel sheet comprising making a slab heating temperature 1280&#xb0; C. or less, annealing hot rolled sheet by (a) a process of heating it to a predetermined temperature of 1000 to 1150&#xb0; C. to cause recrystallization, then annealing by a temperature lower than that of 850 to 1100&#xb0; C. or by (b) decarburizing in annealing the hot rolled sheet so that a difference in amounts of carbon of the steel sheet before and after annealing the hot rolled sheet becomes 0.002 to 0.02 mass % and performing the heating in the temperature elevation process of the decarburization annealing under conditions of a heating rate of 40&#xb0; C. or more, preferably 75 to 125&#xb0; C./s while the temperature of the steel sheet is in a range from 550&#xb0; C. to 720&#xb0; C. and utilizing induction heating for rapid heating in the temperature elevation process of decarburization annealing.

Method of production of grain-oriented electrical steel sheet with high magnetic flux density

The present invention provides a grain-oriented electrical steel sheet product having a superior corrosion resistance, annealing resistance, film tension, and the like in insulating treatment based on a phosphate not containing chromium and a treatment agent for the same, so provides grain-oriented electrical steel sheet having an insulating film not containing chromium characterized by the insulating film containing a phosphate and one or more compounds selected from inorganic compounds of Fe, Ni, Co, Cu, Sr, and Mo in an amount, as metal elements, of 0.06 to 2.10 moles per mole of phosphate, and an insulating film agent of the same.

Grain-oriented electrical steel sheet having insulating film not containing chromium and insulating film agent of same

Grain-oriented electrical steel sheet superior in core loss characteristic containing Si: 0.8 to 7 mass % and having a secondary recrystallized texture with a {110}&#x3c;001&#x3e; orientation as the main orientation, characterized in that average deviation angles &#x3b1;, &#x3b2;, and &#x3b3; from the {110}&#x3c;001&#x3e; ideal orientation of the secondary recrystallized texture satisfy (&#x3b1;+&#x3b2;)&#x2266;&#x3b3;, where &#x3b1;: average deviation angle from {110}&#x3c;001&#x3e; ideal orientation around rolling surface normal direction (ND) of secondary recrystallized texture, &#x3b2;: average deviation angle from {110}&#x3c;001&#x3e; ideal orientation around traverse direction (TD) of secondary recrystallized texture, and &#x3b3;: average deviation angle from {110}&#x3c;001&#x3e; ideal orientation around rolling direction (RD) of secondary recrystallized texture.

Grain-oriented electrical steel sheet superior in core loss characteristic

A means for treating the end faces of a core which is used for an electrical apparatuses and etc., to give insulation extremely superior in effect of improvement of the insulation, corrosion resistance, adhesiveness, heat resistance, and magnetic properties at a low temperature in a short time without cleaning for removing punching oil, annealing, or other pre-treatment; a core having an insulation coating comprised of a dry film of a pure silicone polymer, modified silicone polymer, and/or mixed silicone polymer as a silicone compound on the core end faces and having an average film thickness of at least 0.5 &#x3bc;m, a breakdown voltage of at least 30V, and a heat resistance in the air of at least 400&#xb0; C.; and a method of production comprised of forming a core, then dipping it in or spraying it by one or more types of a pure silicone polymer, modified silicone polymer, and/or mixed silicone polymer as an insulation coating.

Core having superior end face insulation and method of treating core end faces to give insulation coating

A method for producing a grain-oriented electrical steel sheet excellent in magnetic property, comprising the steps of; heating a slab containing a prescribed amount of Al to a temperature of 1,200&deg; C. or higher, hot-rolling the slab into a hot-rolled strip, annealing the strip as required, cold-rolling it once or twice or more with intermediate annealing(s), and decarburization annealing the cold rolled sheet, and final box annealing after the application of an annealing separator to prevent strip sticking during the annealing, characterized by heating the slab to a temperature (slab heating temperature Ts (&deg; C.)) higher than the complete solution temperature of substances having intensities as inhibitors and nitriding treating the decarburization annealed steel sheet before the commencement of secondary recrystallization during the final box annealing.

Method for producing a grain-oriented electrical steel sheet excellent in magnetic properties

A quartz glass component having a projection on a flat face is manufactured by molding a quartz glass body at a high temperature and under high pressure. The heating temperature is set to a range of from 1800.degree. to 2000.degree. C. and slight pressure is applied by the female die which forms the projection, or pressure in a direction against gravity. The molding die includes a graphite frame surrounding a molding space formed by a female die and a receiving die sandwiching the quartz glass body in the graphite frame. The space between the receiving die and the female die is width-reducible, the compositions of the graphite frame and the two graphite dies are made to differ, the female die and receiving die contacting the quartz glass body during pressure molding have a plurality of gas-permeable micropores such as in sintered graphite for example and are formed by a high-purity graphite material having air permeability.

Method for manufacturing quartz glass components and molding frame

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Tokyo, Japan

Norikazu Fujii