GB2177421A - Sintered body of silicon carbide - Google Patents
Sintered body of silicon carbide Download PDFInfo
- Publication number
- GB2177421A GB2177421A GB08609069A GB8609069A GB2177421A GB 2177421 A GB2177421 A GB 2177421A GB 08609069 A GB08609069 A GB 08609069A GB 8609069 A GB8609069 A GB 8609069A GB 2177421 A GB2177421 A GB 2177421A
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- Prior art keywords
- silicon carbide
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- weight
- sintered body
- parts
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/515—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics
- C04B35/56—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbides or oxycarbides
- C04B35/565—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbides or oxycarbides based on silicon carbide
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Ceramic Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Ceramic Products (AREA)
Abstract
A sintered body of silicon carbide comprises 50 to 97 percent by weight of SiC, 1 to 10 percent by weight of a metal nitride, 1 to 10 percent by weight of carbon and 1 to 30 percent by weight of alumina. The metal nitride may be aluminium nitride or titanium nitride. In one method the SiC, metal nitride and carbon in the appropriate amounts are mixed by means of an aluminium mill so as to contain the appropriate amount of alumina.
Description
SPECIFICATION
Sintered body of silicon carbide and method for manufacturing the same
The present invention relates to a sintered body of silicon carbide and to a method for manufacturing the same. In particular,this invention relates two a highstrength sintered body of silicon carbide used as a fire-resistant material, a high-strength material and an abrasion-resistant material.
Conventionally, sintered bodies of silicon carbide have been in general use because of their superior heat resistance and thermal shock resistance. The sintered bodies are produced bysintering under pressure or at normal pressure. The sintering under pressure provides compact and high-puritysintered bodies, butthe sintering can be applied onlyto a product having a simple shape. Moreoverthe sintering requires a complex and expensive apparatus.
In the case of sintering at normal pressure, boron (B) or boron carbide (B4C) is added as sintering aid with carbon (C), and the sintering is carried out at 1 950"C to 2100"C,for example, as described in Japanese Patent
Publications No.57-40109, No.58-14390 or No.
59-34147. The sintering of conventional silicon carbide requires a high temperature of 1950to 2100"C.
Sintering at 2000 C and above is necessary where specific properties are desirable. Sintering at such a high temperature requires a considerably largefur nace and leads to an increase of production cost.
Furthermore, sintering at normal pressure is a solidphase reaction which is accomplished by the addition of boron, boron carbide or carbon, and therefore, the properties of sintered bodies are affected by the dispersion of the sintering aid. Thus, sintered bodies of silicon carbidetend to have defects and to fluctuate in strength. Also, the conventional sintered bodies of silicon carbide have bending strengths of from about 500 to 700 MPa at room temperature.
It is an object of this invention to provide an improved high-strength sintered body ofsilicon carbide.
Another object ofthis invention is to provide a method for manufacturing a high-strength sintered body of silicon carbide.
Another object ofthis invention isto provide an engineering ceramic of silicon carbide.
This invention provides a sintered body of silicon carbide comprising from about 50 to 97 percent by weight of silicon carbide, from about 1 to 10 percent by weight of a metal nitride, from about 1 to 10 percent by weight of carbon and from about 1 to 30 percent by weight of alumina.
Also, in this invention a method for manufacturing a sintered body ofsilicon carbide is provided which comprises the steps of mixing a ceramic material comprising from about 50 to 97 parts by weight of silicon carbide, from about 1 ta 10 parts by weight of metal nitride, from about 1 to 10 parts byweightaf carbon and from about 1 to 30 parts byweight of alumina; forming the mixture into the shape of a desired body; and sintering the formed body.
Further, inthis invention a method for manufactur- ing a sintered body of silicon carbide comprises the steps of adding a ceramic material comprising from about 50 to 97 parts by weight of silicon carbide, from about 1 to 10 parts byweightofa metal material and from about 1 to 10 parts by weight of carbon to an alumina mill; mixing the ceramic material by means ofthe alumina mill so asto contain from about 1 to 30 parts byweightofaluminatothe ceramic mixture; formingthe mixture intotheshapeofa desired body; and sintering the formed body.
Further objects, features and advantages of this invention will become apparent from the description of preferred embodiments which follows.
The surface of a silicon carbide particle is oxidized by air even at normal temperature. The oxidation is severe particularly in the case where the particles are extremely fine, such as 1 micron or less, because such fine particles have a large surface area per unit of volume.
Aluminum nitride is a sintering aid that permits the SiC-AIN-C system to advance to the liquid-phase reaction. Therefore, aluminum nitride is preferable to boron or boron carbide as a sintering aid in that aluminum nitride provides a more homogeneous sintered body. However, aluminum nitride is easily affected by oxygen in silicon carbide, and aluminum nitride is not added to silicon carbide containing more than about 1 percent by weight of oxygen or having a large specific surface area. Accordingly, the oxygen content in silicon carbide on the specific surface area of silicon carbide particles should be as low as possible in the case where aluminum nitride is used as a sintering aid.In otherwords, if aluminum nitride isto be added to silicon carbide, it is necessary to keep the oxygen content in the silicon carbide as low as possible and to keep the specific surface area ofthe silicon carbide as small as possible. For this reason, fine particles of silicon carbide are not used if aluminum nitride is to be added to silicon carbide.
However, fine particles are generally preferable to provide compact and high-strength sintered bodies.
The present invetors have discovered that it is possible to control the interference by oxygen contained in silicon carbide ifthe reaction system contains carbon. Carbon is added to silicon carbide to eliminate oxygen from silicon carbide, and aluminum nitride is added as a sintering aid so thatthe sintering is carried out under an ideal condition. Aluminum nitride added to silicon carbide reaches liquid-phase at sintering temperatures without being affected by oxygen in the silicon carbide.Thus,aluminum in the liquid-phase is uniformly replaced by silicon, and the resultant sintered body is homogeneous and has a high strength.
According to the present invention, alumina is also added to the composition. The alumina is partly reduced by carbon, and active aluminum is formed.
The active aluminum exists in the form of(X-A1203 at the boundary of the grains ofthe sintered silicon carbide. The coefficient ofthermal expansion of silicon carbide differs from that of alumina existing in thesinteredstructureofsilicon carbide. The difference eliminates the strain of the sintered body. Thus the sinteredbodyofsilicon carbide in this invention has a high strength, e.g., as high as 900 MPa. Also, the sintered body has a very high reliability with a Weibull coefficient of 15.
In view of the foregoing, the following composition has been provided according to this invention: silicon carbidefrom about 50 to 97 percentbyweight; metal nitride-from about 1 to 10 percent by weight; carbon-from about 1 to 10 percent by weight; and alumina-from about 1 to 30 percentbyweight.
If the content of metal nitride, such as aluminum nitride, is less than about 1 percent by weight, the resultant sintered body of silicon carbide is less compact and low in density. Such a sintered body is notsatisfactoryin bonding power. Conversely, if the content of metal nitride exceeds about 10 percent by weight, the sintering of silicon carbide is notaccom- plished satisfactorily, and the resultantsintered body is not satisfactory in strength. In this invention, the content of metal nitride is preferably from about 1 percentto 5 percent by weight. Also, titanium nitride may be used as the metal nitride instead of aluminum nitride in this invention.
Also, if the content of carbon is less than about 1 percent weight, the resultant sintered body of silicon carbide is compact in structure, but has a low strength at high temperatures. Conversely, if the content ofcarbon exceeds about 10 percent by weight, the resultant sintered body has a low density and weak bonding power between grains. Moreover, surplus carbon prevents the sintering of silicon carbide and gives free carbon which adversely affects the oxidation resistance ofthe sintered body.
Furthermore, ifthe content ofalumina is less than about 1 percent by weight, the strength of the resultant sintered body is not improved. Conversely, if the content of alumina exceeds about 30 percent by weight, the strength of the resultant sintered body is not satisfactory at high temperature. In this invention, the content ofalumina is preferably from about 5 percent to about 20 percent by weight in terms ofthe bending strength, more preferably from about 10 percentto about 20 percent by weight.
A method for manufacturing a sintered body of thins invention is carried out asfollows: Atfirst, silicon carbide powder is pulverized into powder having adequate specific surface area by means of a pot mill containing anhydrous acetone. In this invention, silicon carbide preferably has a specific surface area ofgreaterthan about 20 m2/g, more preferably g reaterthan about 40 m2/g. The surface of the resultant silicon carbide powder is partially oxidized because the silicon carbide powder is exposed to air at normal temperature.Next, from about 50 to 97 parts by weight ofthe silicon carbide powder, from about 1 to 10 parts by weight of a metal nitride, such as aluminum nitride ortitanium nitride, from about 1 to 10 parts by weight of carbon and from about 1 to 30 parts by weight of alumina are mixed with phenol resin as a binder by means of a pot mill. In this invention an alumina pot mill is preferably used as the pot mill. If an alumina pot mill is used, alumina need not be added to the starting material, because alumina is mixed with the starting material from the alumina pot mill during the mixing step. Further, the mixture is formed and sintered at normal pressure in an inert gas atmosphere. In this invention, the sintering of silicon carbide is carried out at a temperature offrom about 1700"C to 20500C.If the temperature of the sintering is less than about 1700"C, the sintering is not accomplished satisfactorily, and the resultant sintered body is poor in strength. Conversely, if the temperature of the sintering exceeds about 2050"C, the density of the resultant sintered body is poor, and the strength is deteriorated due to evaporation of alumina. The sintering temperature of silicon carbide in this invention is preferably from about 1700 Cto 1900 C.Also, the sintering of silicon carbide in this invention is preferably carried out in an inert gas such as argon or helium.
The invention will be more clearly understood with reference to the following examples:
Example 1
Silicon carbide powder having an average particle size of 1 micron was pulverized into powder having an average particle size of 0.5 micron by means of a pot mill containing anhydrous acetone. The silicon car
bide powder was mixed with alumina (awl203), carbon (C) and aluminum nitride (AIN) by means of a pot mill.
The mixture was formed into a prism by addition of phenol resin as a binder and then wassintered at
normal pressure in an argon atmosphereatatemper- ature of 1 700"C to 20500C as shown in Table 1. As the
result, there were obtained sintered bodies of silicon
carbide each having a composition as shown in Table 1. Also, each sintered body of silicon carbide has a
density equivalent to 80 percentto 98 percent ofthe theoretical value of silicon carbide (3.21 g/cm3).The
bending strengths ofthe sintered bodies at a tempera
ture of 20"C are shown in Table 1.Table 1 also shows
the bending strength of Comparative Example 1 which
contains 35 percent by weight of alumina, and
Comparative Example 2 which comprises silicon
carbide, carbon and aluminum nitride.
Table 1
Composition ( arts by weight) Sintering Bending SiC I A120 C A1N Temperature( C) Strength (MPa) 1-' 75 20 4 2 1750 500 Example 1-2 79 15 4 2 1800 900 1-3 84 10 4 2 1800 800 1-5 89 5 5 2 1850 700 Comparative 1 59 35 4 2 1800 500 Example 2 - 2 94 0 4 2 1850 500 As is apparentfrom Table 1, the sintered bodies in this invention have a high bending strength of 700 to 900 MPa and are superior to the conventional sintered bodies of silicon carbide having strengths of 500 to 700 MPa.Particularly, Example 1-2 showed the highest bending strength of 900 MPa when it was sintered at a temperature of 1800 C. On the other hand, Comparative Example 1 containing 35 percent by weight of alumina and Comparative Example 2 containing no alumina are inferiortothe Examples according to the invention in terms of the bending strength.
Example 2
Silicon carbide powder having an average particle size of 1 micron was pulverized by means of a pot mill containing an hydros acetone. Thus, there was obtained silicon powder having different specific surface areas as shown in Table 2. The resultant powderwas exposed to air at normal temperature so that the surface ofthe silicon carbide particles was partially oxidized. Next, 94 parts by weight of the partially oxidized silicon carbide powder was mixed with 10 parts by weight ofalumina (awl203),4 parts by weight of carbon (C) and 2 parts by weight of aluminum nitride (AIN) by means of a pot mill.The mixture was formed into a prism by addition of phenol resin as a binder and then was sintered at normal pressure in an argon atmosphere at a temperature of 1 8005C. As the result, there were obtained compact bodies each having a density equivalent to 80 percent to 98 percent of the theoretical value of silicon carbide. The bending strengths ofthe sintered bodies at a temperature of 20"C are shown inTable2.
Table 2
Bending Specific Surface Area Strength of SiC (n2 ) (MPa Comparative 3 10 500 fleaple 4 15 550 2-1 20 680 z ples 2-2 | 25 750 2-3 40 830 As is apparent from Table 2, the bending strength becomes high as the specific surface area of silicon carbide exceeds 20 m2/g.Particularly, when the specific surface area of silicon carbide is 40 m2/g, the sintered body of silicon carbide has a bending strength of 830 MPa.
Example 3
Silicon carbide powder having an average particle size of 1 micron was pulverized into powder having a specific surface area of 45 m2/g by means of a pot mill containing anhydrous acetone. Ninety-four(94) parts by weight of the silicon carbide powder was compounded with 4 parts by weight of carbon and 2 parts by weight of aluminum nitride. The compounded powderwasmixed by means of an alumina pot mill with phenol resin as a binder. Then the mixture was formed into a prism and was sintered at normal pressure in an argon atmosphere at a temperature of 1850"C. As the result, there was obtained a compact sintered body having a density of 3.32 g/cm3.The sinteredbodycontained 11 percentbyweightof alumina mixed from the alumina pot mill during the mixing step. The bending strength of the sintered bodywas860MPa at a temperature of 20 C.
As mentioned above, the sintered body of silicon carbide in this invention is superior to the conventional sintered body of silicon carbide in terms ofthe bending strength. The bending strength of the sintered body in this invention is as high as 900 MPa at a temperature of 20"C if optimum conditions are selected. Also, the sintering temperature forthe conventional sintered body ofsilicon ca rbide is 1 900eCtO 21 OO"C, butthe sintered body of silicon carbide in this invention is sintered at a lower temperature offrom about 1700into 2050 C. Particularly, in this invention it is possible to carry out sintering at a temperature of 1 9005C or below which has been considered to be too low for practical sintering.
Accordingly,the sintered body of silicon carbide in this invention is suitable for engineering ceramics such as conveyor rolls, rotatorsegments,wire drawing dies or gas heat exchanges.
Claims (30)
1. Asintered bodyof silicon carbidecomprising from about 50 percent to 97 percent by weight of silicon carbide, from about 1 percent to 10 percent by weight of a metal nitride, from about 1 percent to 10 percent by weight of carbon and from about 1 percent to 30 percent by weight of alumina.
2. A sintered body of silicon carbide according to
Claim 1, wherein the content of alumina is from about 5 percent to 20 percent by weight.
3. A sintered body of silicon carbide according to
Claim 1,wherein the content of alumina is from about 10 percentto 20 percent by weight.
4. A sintered body of silicon carbide according to
Claim 1, wherein the content of metal nitride is from about 1 percent to 5 percent by weight.
5. A sintered body of silicon carbide according to
Claim 1,whereinthedensityisequivalentto80 percent to 98 percent ofthetheoretical value of silicon carbide.
6. A sintered body of silicon carbide according to
Claim 1, wherein said metal nitride comprises alumi
num nitride.
7. A sintered body of silicon carbide according to
Claim 1, wherein said metal nitridecomprisestita- nium nitride.
8. A method for manufacturing a sintered body of
silicon carbide comprising the steps of: mixing
ceramic material comprising from about 50 to 97
parts by weight of silicon carbide, from about 1 to 10
parts byweightofa metal nitride, from about 1 to 10
parts by weight of carbon and from about 1 to 30 parts byweightofalumina; forming the mixture intothe
shape of a desired body; and sintering the formed
body.
9. A method according to Claim 8, wherein said
silicon carbide comprises particles having a specific
surface area of greater than about 20 m2/g.
10. A method according to Claim 8, wherein said
silicon carbide comprises particles having a specific
surface area of greaterthan about 40 m2/g.
11. A method according to Claim 8, wherein said sintered step is carried out in an inert gas atmosphere.
12. A method according to Claim 11, wherein said inert gas comprises argon or helium.
13. A method according to Claim 8, wherein said sintering step is carried outatatmosphericpressure.
14. A method according to Claim 13, wherein said sintering step is carried out at a temperature of from about 1700 Cto 2050 C.
15. A method according to Claim 8, wherein said sintering step is carried out attemperature of from about1700 Cto 1900 C.
16. A method according to Claim 8, wherein said metal nitride comprises aluminum nitride.
17. A method according to Claim 8, wherein said metal nitride comprises titanium nitride.
18. Amethodformanufacturing asinteredbody of silicon carbide comprising the steps of:
adding a ceramic material comprising from about 50 to 97 parts byweightofsilicon carbide, from about 1 to 10 parts by weight of a metal nitride and from about 1 to 10 parts by weight of carbon to an alumina mill;
mixing said ceramic material by means of said alumina mill so as to contain from about 1 to 30 parts by weight ofalumina to the ceramic mixture;
forming the mixture into the shape of a desired body; and sinteringtheformed body.
19. A method according to Claim 18, wherein said sintering step is carried out at temperature of from about 1700 C to 2050 C.
20. A method according to Claim 18, wherein said sintering step is carried out at temperature of from about 1700 Cto 1900 C.
21. A method according to Claim 18, wherein said sintering step is carried out at normal atmospheric pressure.
22. A method according to Claim 18,whereinsaid sintering step is carried out in an inert gas atmosphere.
23. A method according to Claim 22, wherein said inert gas comprises argon or helium.
24. A method according to Claim 18, wherein said silicon carbide comprises particles having a specific surface area at least about 20 m2/g.
25. A method according to claim 18,wherein said silicon carbide comprises particles having a specific surface area at least about 40 m2/g.
26. A method according to Claim 18, wherein said metal nitride comprises aluminum nitride.
27. Amethod accordingto claim 18, wherein said metal nitride comprises titanium nitride.
28. An engineering ceramic comprising a sintered body of silicon carbide as defined by claim 1.
29. Asintered body of silicon carbide substantially as hereinbefore described.
30. A method of manufacturing a sintered body of silicon carbide substantially as hereinbefore described.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60106043A JPS62113762A (en) | 1985-05-20 | 1985-05-20 | Silicon carbide base high strength sintered body |
| JP60106041A JPS62113761A (en) | 1985-05-20 | 1985-05-20 | High strength sintered body and manufacture |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB8609069D0 GB8609069D0 (en) | 1986-05-21 |
| GB2177421A true GB2177421A (en) | 1987-01-21 |
| GB2177421B GB2177421B (en) | 1989-07-19 |
Family
ID=26446230
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8609069A Expired GB2177421B (en) | 1985-05-20 | 1986-04-14 | Sintered body of silicon carbide and method for manufacturing the same |
Country Status (3)
| Country | Link |
|---|---|
| DE (1) | DE3615861A1 (en) |
| FR (1) | FR2581986B1 (en) |
| GB (1) | GB2177421B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2262943A (en) * | 1991-12-27 | 1993-07-07 | Atomic Energy Authority Uk | A nitrogen-strengthened alloy |
| GB2321907A (en) * | 1997-02-10 | 1998-08-12 | Bayer Ag | A liquid phase-sintered,electrically conductive and oxidation-resistant ceramic material,a process for producing it and its use |
| GB2302335B (en) * | 1995-06-19 | 1998-08-26 | Ngk Spark Plug Co | A low-voltage type igniter plug having a semiconductor for use in jet and other internal combustion engines and a method of making the semiconductor |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3832706C1 (en) * | 1988-04-07 | 1989-04-27 | Feldmuehle Ag, 4000 Duesseldorf, De | |
| DE3832692A1 (en) * | 1988-09-27 | 1990-03-29 | Leybold Ag | SEALING ELEMENT WITH A SHUT-OFF BODY MADE OF A METAL OR NON-METAL MATERIAL AND METHOD FOR APPLYING HARD MATERIAL LAYERS TO THE SHUT-OFF BODY |
Citations (12)
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|---|---|---|---|---|
| GB2004906A (en) * | 1977-09-09 | 1979-04-11 | United Technologies Corp | Alumina-coated silicon carbide particles |
| EP0004031A1 (en) * | 1978-03-03 | 1979-09-19 | Elektroschmelzwerk Kempten GmbH | High density, polycrystalline silicon carbide articles and method for their preparation by pressureless sintering |
| GB1556173A (en) * | 1975-06-05 | 1979-11-21 | Carborundum Co | Sintered silicon carbide ceramic body |
| GB2023185A (en) * | 1978-06-15 | 1979-12-28 | Carborundum Co | Co-sintered Silicon Carbide- aluminium Nitride Products and a Method for their Production |
| GB1568063A (en) * | 1975-10-18 | 1980-05-21 | Watanabe H | Method for producing metal nitride sintered mouldings |
| GB2043111A (en) * | 1979-02-15 | 1980-10-01 | Coors Porcelain Co | Manufacturing silicon carbide compacts |
| GB2082165A (en) * | 1980-07-17 | 1982-03-03 | Asahi Glass Co Ltd | Silicon carbide ceramic |
| GB2104103A (en) * | 1981-08-21 | 1983-03-02 | Shinetsu Chemical Co | Forming shaped silicon carbide bodies |
| EP0093532A1 (en) * | 1982-04-30 | 1983-11-09 | United Kingdom Atomic Energy Authority | Production of reaction-bonded silicon carbide bodies |
| GB2125066A (en) * | 1982-07-29 | 1984-02-29 | Mamoru Omori | Sintered silicon carbide molding and process for production thereof |
| GB2133042A (en) * | 1982-12-08 | 1984-07-18 | Asahi Glass Co Ltd | Silicon carbide sintered article and process for its production |
| GB2140823A (en) * | 1980-06-23 | 1984-12-05 | Kennecott Corp | Sintered silicon carbide-titanium diboride mixtures and articles thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5290507A (en) * | 1976-01-26 | 1977-07-29 | Shinagawa Refractories Co | Refractories*compositions therefor and manufacture |
| US4141740A (en) * | 1978-02-23 | 1979-02-27 | University Of Utah | Solid solution and process for producing a solid solution |
| US4332755A (en) * | 1978-06-15 | 1982-06-01 | Kennecott Corporation | Sintered silicon carbide - aluminum nitride articles and method of making such articles |
| DE2912443A1 (en) * | 1979-03-29 | 1980-10-16 | Starck Hermann C Fa | Dense silicon carbide mouldings made by sintering without pressure - where aluminium and carbon are mixed with silicon carbide powder before moulding |
| JPS591886B2 (en) * | 1980-08-20 | 1984-01-14 | 三菱重工業株式会社 | Boundary layer control method and device |
| JPS5814390A (en) * | 1981-07-17 | 1983-01-27 | Matsushita Electric Ind Co Ltd | Detector for tape position |
| JPS5891066A (en) * | 1981-11-27 | 1983-05-30 | 旭硝子株式会社 | Silicon carbide sintered body and manufacture |
| JPS5934147A (en) * | 1982-08-20 | 1984-02-24 | Nissan Motor Co Ltd | Flaw detector for rotor blade |
-
1986
- 1986-04-14 GB GB8609069A patent/GB2177421B/en not_active Expired
- 1986-05-07 FR FR8606611A patent/FR2581986B1/en not_active Expired - Fee Related
- 1986-05-10 DE DE19863615861 patent/DE3615861A1/en active Granted
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1556173A (en) * | 1975-06-05 | 1979-11-21 | Carborundum Co | Sintered silicon carbide ceramic body |
| GB1568063A (en) * | 1975-10-18 | 1980-05-21 | Watanabe H | Method for producing metal nitride sintered mouldings |
| GB2004906A (en) * | 1977-09-09 | 1979-04-11 | United Technologies Corp | Alumina-coated silicon carbide particles |
| EP0004031A1 (en) * | 1978-03-03 | 1979-09-19 | Elektroschmelzwerk Kempten GmbH | High density, polycrystalline silicon carbide articles and method for their preparation by pressureless sintering |
| GB2023185A (en) * | 1978-06-15 | 1979-12-28 | Carborundum Co | Co-sintered Silicon Carbide- aluminium Nitride Products and a Method for their Production |
| GB2043111A (en) * | 1979-02-15 | 1980-10-01 | Coors Porcelain Co | Manufacturing silicon carbide compacts |
| GB2140823A (en) * | 1980-06-23 | 1984-12-05 | Kennecott Corp | Sintered silicon carbide-titanium diboride mixtures and articles thereof |
| GB2082165A (en) * | 1980-07-17 | 1982-03-03 | Asahi Glass Co Ltd | Silicon carbide ceramic |
| GB2104103A (en) * | 1981-08-21 | 1983-03-02 | Shinetsu Chemical Co | Forming shaped silicon carbide bodies |
| EP0093532A1 (en) * | 1982-04-30 | 1983-11-09 | United Kingdom Atomic Energy Authority | Production of reaction-bonded silicon carbide bodies |
| GB2125066A (en) * | 1982-07-29 | 1984-02-29 | Mamoru Omori | Sintered silicon carbide molding and process for production thereof |
| GB2133042A (en) * | 1982-12-08 | 1984-07-18 | Asahi Glass Co Ltd | Silicon carbide sintered article and process for its production |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2262943A (en) * | 1991-12-27 | 1993-07-07 | Atomic Energy Authority Uk | A nitrogen-strengthened alloy |
| GB2302335B (en) * | 1995-06-19 | 1998-08-26 | Ngk Spark Plug Co | A low-voltage type igniter plug having a semiconductor for use in jet and other internal combustion engines and a method of making the semiconductor |
| US5852340A (en) * | 1995-06-19 | 1998-12-22 | Ngk Spark Plug Co., Ltd. | Low-voltage type igniter plug having a semiconductor for use in jet and other internal combustion engines and a method of making the semiconductor |
| GB2321907A (en) * | 1997-02-10 | 1998-08-12 | Bayer Ag | A liquid phase-sintered,electrically conductive and oxidation-resistant ceramic material,a process for producing it and its use |
| GB2321907B (en) * | 1997-02-10 | 2000-11-15 | Bayer Ag | A liquid phase-sintered,electrically conductive and oxidation-resistant ceramic material,a process for producing it and its use |
| US6156238A (en) * | 1997-02-10 | 2000-12-05 | Bayer Ag | Liquid phase-sintered, electrically conductive and oxidation-resistant ceramic material, a process for producing it and its use |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2177421B (en) | 1989-07-19 |
| FR2581986B1 (en) | 1992-02-07 |
| FR2581986A1 (en) | 1986-11-21 |
| DE3615861A1 (en) | 1986-11-20 |
| GB8609069D0 (en) | 1986-05-21 |
| DE3615861C2 (en) | 1990-10-04 |
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| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19990414 |