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1.发明授权公开(公告)号：US6410468B2
公开(公告)日：2002-06-25
申请号：US89973601
申请日：2001-07-05
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： NAKAHATA SEIJI , YAMAKAWA AKIRA
IPC: C04B35/591 , C04B35/626
CPC classification number: C04B35/591
Abstract: A slurry Si-base composition comprising an Si powder having a thickness of a surface oxide film ranging from 1.5 to 15 nm, 50 to 90% by weight of water, 0.2 to 7.5% by weight, in terms of oxide, of a sintering aid and 0.05 to 3% by weight of a dispersant, the Si-base composition having a pH value adjusted to 8-12. This slurry Si-base composition is produced by a process which comprises subjecting Si powder to oxidation treatment at 200 to 800° C. in air, adding 50 to 90% by weight of water, 0.2 to 7.5% by weight, in terms of oxide, of a sintering aid and 0.05 to 3% by weight of a dispersant to the oxidized Si powder and performing such a pH adjustment that the resultant mixture has a pH value of 8 to 12. The slurry Si-base composition not only enables producing a ceramic of Si3N4 at a lowered cost without the need to install explosionproof facilities but also allows the obtained Si3N4 ceramic having a relative density of at least 96% and a flexural strength of at least 800 MPa can be obtained.
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公开(公告)号：DE69631733T2
公开(公告)日：2005-03-24
申请号：DE69631733
申请日：1996-11-12
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： NAKAHATA SEIJI , YAMAKAWA AKIRA
IPC: C04B35/591 , C04B35/626
Abstract: A slurry Si-base composition comprising an Si powder having a thickness of a surface oxide film ranging from 1.5 to 15 nm, 50 to 90% by weight of water, 0.2 to 7.5% by weight, in terms of oxide, of a sintering aid and 0.05 to 3% by weight of a dispersant, the Si-base composition having a pH value adjusted to 8 - 12. This slurry Si-base composition is produced by a process which comprises subjecting Si powder to oxidation treatment at 200 to 800 DEG C in air, adding 50 to 90% by weight of water, 0.2 to 7.5% by weight, in terms of oxide, of a sintering aid and 0.05 to 3% by weight of a dispersant to the oxidized Si powder and performing such a pH adjustment that the resultant mixture has a pH value of 8 to 12. The slurry Si-base composition not only enables producing a ceramic of Si3N4 at a lowered cost without the need to install explosionproof facilities but also allows the obtained Si3N4 ceramic having a relative density of at least 96% and a flexural strength of at least 800 MPa can be obtained.
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公开(公告)号：DE69631733D1
公开(公告)日：2004-04-08
申请号：DE69631733
申请日：1996-11-12
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： NAKAHATA SEIJI , YAMAKAWA AKIRA
IPC: C04B35/591 , C04B35/626
Abstract: A slurry Si-base composition comprising an Si powder having a thickness of a surface oxide film ranging from 1.5 to 15 nm, 50 to 90% by weight of water, 0.2 to 7.5% by weight, in terms of oxide, of a sintering aid and 0.05 to 3% by weight of a dispersant, the Si-base composition having a pH value adjusted to 8 - 12. This slurry Si-base composition is produced by a process which comprises subjecting Si powder to oxidation treatment at 200 to 800 DEG C in air, adding 50 to 90% by weight of water, 0.2 to 7.5% by weight, in terms of oxide, of a sintering aid and 0.05 to 3% by weight of a dispersant to the oxidized Si powder and performing such a pH adjustment that the resultant mixture has a pH value of 8 to 12. The slurry Si-base composition not only enables producing a ceramic of Si3N4 at a lowered cost without the need to install explosionproof facilities but also allows the obtained Si3N4 ceramic having a relative density of at least 96% and a flexural strength of at least 800 MPa can be obtained.
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公开(公告)号：DE69808575T2
公开(公告)日：2003-08-07
申请号：DE69808575
申请日：1998-09-04
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： MIYANAGA MICHIMASA , NAKAHATA SEIJI , YAMAKAWA AKIRA
IPC: C04B35/591 , C04B35/597 , C04B35/599
Abstract: Provided is a silicon nitride sintered body prepared through nitriding reaction of Si. The silicon nitride sintered body consists of crystal grains mainly composed of silicon nitride and/or SIALON and a grain phase, components forming the grain boundary phase consist of a first component including at least one element selected from a group of Na, K, Mg, Ca and Sr and a second component including at least one element selected from a group of Y and lanthanoid series elements, the molar ratio of the first component to the second component is in the range of 1:1 to 6:1 in terms of oxides, the mean breadth and the mean length of the crystal grains are not more than 0.1 mu m and not more than 3 mu m respectively, and the standard deviation of the mean length in the sintered body is within 1.5 mu m.
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公开(公告)号：DE69627078D1
公开(公告)日：2003-05-08
申请号：DE69627078
申请日：1996-07-25
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： MATSUURA TAKAHIRO , KAWAI CHIHIRO , YAMAKAWA AKIRA
Abstract: A ceramics porous body having excellent acid resistance and alkali resistance as well as excellent mechanical strength and durability which can be employed as a filter or a catalytic carrier is provided. A silicon nitride porous body contains a plurality of silicon nitride crystal grains with pores formed in grain boundary parts thereof, or comprises a body part and a pore part so that the body part is formed by a plurality of silicon nitride crystal grains and the pore part forms a three-dimensional network structure. The body part is formed by at least 90 vol. % of silicon nitride crystal grains, which are directly bonded to each other for forming the body part. The porous body which is mainly composed of silicon nitride is brought into contact with an acid and/or an alkali so that a component other than silicon nitride is partially or entirely dissolved and removed, thereby preparing a porous body.
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Patent Agency Ranking
公开(公告)号：DE69625174D1
公开(公告)日：2003-01-16
申请号：DE69625174
申请日：1996-06-17
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： YAMAGIWA MASAMICHI , NISHIOKA TAKAO , TAKEUCHI HISAO , YAMAKAWA AKIRA
Abstract: An object of the present invention is to provide a sliding part having a crowning configuration by effecting surface hardening at a portion constituted by steel and a method for manufacturing the same part. The configuration and volume of crowning can be adjusted by heat treatment and processing after the surface hardening, and the sliding part is constituted by a single steel unit or includes at least one portion of a member forming a sliding surface formed into the crowning configuration through surface hardening is jointed to or fitted in a steel sliding part main body and made of ceramics.
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公开(公告)号：DE69808575D1
公开(公告)日：2002-11-14
申请号：DE69808575
申请日：1998-09-04
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： MIYANAGA MICHIMASA , NAKAHATA SEIJI , YAMAKAWA AKIRA
IPC: C04B35/591 , C04B35/597 , C04B35/599
Abstract: Provided is a silicon nitride sintered body prepared through nitriding reaction of Si. The silicon nitride sintered body consists of crystal grains mainly composed of silicon nitride and/or SIALON and a grain phase, components forming the grain boundary phase consist of a first component including at least one element selected from a group of Na, K, Mg, Ca and Sr and a second component including at least one element selected from a group of Y and lanthanoid series elements, the molar ratio of the first component to the second component is in the range of 1:1 to 6:1 in terms of oxides, the mean breadth and the mean length of the crystal grains are not more than 0.1 mu m and not more than 3 mu m respectively, and the standard deviation of the mean length in the sintered body is within 1.5 mu m.
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公开(公告)号：DE69526733D1
公开(公告)日：2002-06-20
申请号：DE69526733
申请日：1995-07-27
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： AWAZU TOMOYUKI , TSUZUKI YASUSHI , YAMAKAWA AKIRA
IPC: B28B1/26 , B28B7/46 , C04B35/622
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公开(公告)号：DE69525939D1
公开(公告)日：2002-04-25
申请号：DE69525939
申请日：1995-12-26
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： NAKAHATA SEIJI , TAKEUCHI HISAO , YAMAKAWA AKIRA
IPC: C04B35/591
Abstract: A dense, high-strength silicon nitride (Si3N4) sinter produced by reaction sintering with a shortened nitridation time and an improved productivity. The sinter has an unpaired electron concentration of 10 -10 /cm and is obtained by the reaction sintering of a silicon powder having an unpaired electron concentration of 10 -10 /cm and obtained by annealing a commercially available silicon powder in an atmosphere of other than nitrogen at a temperature of 300-800 DEG C for 3-5 hours. The production process comprises conducting the reaction sintering by mixing the starting powder with a sintering aid and a nitrogen pore forming agent comprising an element having a valency of, especially, +1, to +3 and satisfying the following relationship between RM (the radius of covalent bond of the element) and RSi (the radius of covalent bond of silicon): (RM-RSi)/RSi
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公开(公告)号：DE69518501D1
公开(公告)日：2000-09-28
申请号：DE69518501
申请日：1995-09-20
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： TAKEUCHI HISAO , SOGABE KOICHI , NISHIOKA TAKAO , MATSUURA TAKASHI , YAMAKAWA AKIRA
Abstract: A bonded body of aluminum and silicon nitride firmly bonded to each other which is produced economically, and a light-weight component having an excellent lubrication characteristic as a mechanical component of an internal combustion engine of an automobile. The bonded body includes a base consisting of aluminum as its principal component and a member comprising a silicon nitride sintered body bonded substantially directly to the base. A base material (2) in a powder or bulk form containing aluminum as the principal component and a member (1) comprising a silicon nitride sintered body are put into a mold and are heated under pressure to mutually bond them.
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