JP3062139B2 - Manufacturing method of multilayer ceramics - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a laminated ceramic which is excellent in mechanical properties such as strength and has oxidation resistance and corrosion resistance at high temperatures and which is suitable for a structural material. The present invention relates to a method for producing a laminated ceramic suitable as a material for producing a member, a member for an automobile engine, a heat-resistant member for an ultra-high-speed aircraft, and the like.

[0002]

2. Description of the Related Art Silicon nitride (SiN), sialon (Si)
Non-oxide ceramics such as -Al-ON) and silicon carbide (SiC) have excellent heat resistance, thermal shock resistance and creep resistance at high temperatures. It is expected to be applied to structural members. However, non-oxide ceramics are 1500 ° C
If the temperature becomes higher or lower or higher, deterioration due to the progress of oxidation becomes a problem, so that use at high temperatures is hindered. On the other hand, oxide ceramics have excellent heat resistance and oxidation resistance, but have low mechanical properties such as strength and toughness at high temperatures. Therefore, non-oxide ceramics and oxide ceramics alone cannot satisfy both heat resistance and oxidation resistance and mechanical properties that can withstand use at high temperatures.

[0003]

Therefore, if an oxide layer is formed on the surface of a non-oxide ceramic, it is expected that the oxidation resistance and the corrosion resistance will be improved, and that it will be a mechanical component material that can withstand use at high temperatures. You.

However, in general oxide ceramics, oxide ceramics have a higher coefficient of thermal expansion and different physical properties than non-oxide ceramics. Cracks occur due to residual stress (tensile stress generated on the oxide layer side) generated during the cooling process. Therefore, it is difficult to join and integrate the non-oxide ceramic and the oxide ceramic. Further, even if bonding and integration can be performed in a specific combination of non-oxide ceramics and oxide ceramics, the same prescription cannot be used in other combinations. Therefore, it is extremely difficult to develop a laminated ceramic having satisfactory characteristics suitable for practical use.

The present invention has been made in order to solve such problems of the prior art, and is intended to provide a mechanical component material which has excellent strength and heat resistance, can withstand oxidation and corrosion at high temperatures, and can be used for a long time. The purpose is to provide it easily.

[0006]

Means for Solving the Problems In order to achieve the above object, the present inventors have conducted intensive studies and as a result, have found that non-oxide ceramics containing silicon carbide as a main component and rare earth silicate compounds: RE ₂ SiO ₅ (Wherein RE is a rare earth element selected from the group consisting of Y, Yb, Er and Dy)
They have found that they can be integrated using a silicon oxide layer in a specific state, and have invented a multilayer ceramic of the present invention and a method for producing the same.

[0007] The method for producing a laminated ceramic of the present invention comprises:
Forming a second layer containing silicon oxide having a chemical bond to the first layer on the first layer containing silicon carbide, and a general formula: RE ₂ SiO ₅ (wherein RE is
Y represents a rare earth element selected from the group consisting of Y, Yb, Er and Dy). A third layer containing a rare earth silicate compound represented by Integrating the third layer.

Further, according to the method for manufacturing a laminated ceramic of the present invention, a surface of a first layer containing silicon carbide is oxidized to form a multilayer body of a second layer containing silicon oxide and the first layer. Step and general formula: RE ₂ SiO ₅ (where RE is a
A rare earth element selected from the group consisting of Y, Yb, Er, and Dy), and heating the third layer containing the rare earth silicate compound by contacting the third layer with the silicon oxide layer of the multilayer body. Integrating the first layer and the third layer.

Further, according to the method for producing a laminated ceramic of the present invention, the first layer containing silicon carbide is heated in an oxidizing atmosphere to oxidize the surface of the first layer, thereby forming the first layer and the silicon oxide. Forming a multi-layer body having a second layer containing: a general formula: RE ₂ SiO ₅ (wherein RE in the formula)
Represents a rare earth element selected from the group consisting of Y, Yb, Er and Dy). A third layer containing a rare earth silicate compound represented by the following formula is brought into contact with the second layer of the multilayer body and heated. Integrating the first layer and the third layer.

The first layer is a sintered body containing silicon carbide, and heat for oxidizing the surface of the first layer is 1350 to 17
The heating is performed at a temperature of 00 ° C. for 1 to 500 hours, and the heating for integrating the first layer and the third layer is performed at 1400 to 1700 ° C.
At a temperature of

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Silicon carbide is a ceramic excellent in high-temperature strength, and if it is improved in oxidation resistance and corrosion resistance at high temperatures, it is a suitable material for mechanical parts. This is oxidation resistance,
This is realized by coating the surface of silicon carbide with an oxide ceramic having corrosion resistance. As an oxide for this purpose, a silicate compound of a rare earth element (RE ₂
SiO ₅ or RE ₂ Si ₂ O ₇ , where RE is Y, Y
The present inventors have found that a rare earth element selected from the group consisting of b, Er and Dy is suitable.
The rare earth silicate compound (hereinafter, the rare earth silicate compound is simply referred to as silicate in the present application) has excellent oxidation resistance, a thermal expansion coefficient close to that of silicon carbide, and similar thermal expansion behavior. However, since silicon carbide and silicate are not joined even when they are brought into direct contact with each other and heated, the applicant of the present application disclosed in Japanese Patent Application No. 8-262342 that heat treatment was carried out by interposing alumina at the interface between silicon carbide and silicate. Proposes a method of joining. However, considering components that are used for a long time at high temperatures, such as gas turbines,
It is desired to use a material such as silicon oxide having a lower oxygen permeability than alumina as the bonding material. In view of this, the applicant of the present application has disclosed in Japanese Patent Application No. Hei 9-162900 that a silicon carbide layer and a silicate compound of a rare earth element: RE ₂ Si ₂ O ₇ (R in the formula)
E represents a rare earth element selected from the group consisting of Y, Yb, Er and Dy. Hereinafter, a silicon oxide (SiO ₂ ) layer is interposed between the silicon carbide layer and the disilicate layer, and the silicon carbide layer and the disilicate layer are joined to obtain a laminated ceramic. is suggesting. Although this laminated ceramic is a material excellent in heat resistance and stability against temperature change, in view of the fact that densification of disilicate is relatively difficult, the present applicant further added a silicon carbide layer and a silicate compound of a rare earth element: RE
Development of a laminated ceramic in which a layer of ₂ SiO ₅ (wherein RE is a rare earth element selected from the group consisting of Y, Yb, Er and Dy; this silicate compound is hereinafter simply referred to as monosilicate) is bonded. Tried.

However, even when heating is performed by interposing a layer of silicon oxide powder at the interface between the monosilicate and silicon carbide, the silicon oxide is absorbed by the monosilicate during heating and does not remain at the interface. It is not bonded to silicon carbide. Even when silicon oxide fine powder is deposited on silicon carbide by using a dipping method, an electrophoresis method or a sol-gel method, a bond with monosilicate is not formed. In such a situation, as a result of intensive studies, silicon oxide is absorbed into monosilicate because the bonding between silicon carbide and silicon oxide is weak, and the bonding between silicon carbide and silicon carbide is strong. It has been found that when a layer is used, silicon carbide and monosilicate can be integrated, and a method for manufacturing a multilayer ceramic according to the present invention has been proposed.

[0013] That is, the present invention joins a silicon carbide base material and a monosilicate layer by heat sintering with a silicon oxide layer firmly bonded to the silicon carbide base material at the atomic and molecular level interposed therebetween. In this case, the loss of silicon oxide during heating is suppressed, and a suitably bonded laminated ceramic is manufactured.

Hereinafter, the present invention will be described in more detail.

In the present invention, the silicon oxide used for bonding the silicon carbide layer and the monosilicate layer has a strong bonding state with the silicon carbide layer in order to prevent the silicon oxide from being absorbed by the monosilicate layer and disappearing during heating. A certain silicon oxide layer is used. Although it is not easy to strictly define the silicon oxide layer in the strong bonding state, the present inventor considers that a silicon oxide layer having chemical bonding to the silicon carbide layer is an appropriate definition, The “layer having a chemical bonding property” means a layer bonded by a chemical bond or a layer in a bonded state by chemical adsorption (adsorption by the action of a chemical bonding force) or a layer equivalent thereto.

As a specific example of the “silicon oxide layer having a chemical bond to the silicon carbide layer” in the present invention, for example, the silicon oxide layer is formed by heating a silicon carbide substrate in an oxidizing atmosphere to oxidize the surface. And a silicon oxide layer obtained by laminating silicon oxide powder on a silicon carbide layer and pre-sintering the same. Alternatively, a silicon oxide layer formed by a CVD film forming method after a surface of a silicon carbide base material has been previously cleaned can also be used. When the silicon carbide base material is heated in an oxidizing atmosphere, oxygen enters the silicon carbide sintered body from the surface and the substitution with carbon proceeds, so that silicon oxide is generated, and the silicon oxide layer is formed. A layered body is obtained. As a result, the multilayer body has a state in which a covalent bond or an ionic bond exists between the silicon oxide layer and the silicon carbide, and both layers are firmly joined. On the other hand, when silicon oxide powder is laminated on silicon carbide and pre-sintered, the silicon oxide powder is melted and fused to silicon carbide, and a dense silicon oxide layer firmly bonded to silicon carbide is formed by cooling. You. Further, in the silicon oxide layer formed by the CVD film forming method, silicon oxide molecules are adhered and deposited at an atomic molecular level, and are firmly bonded to silicon carbide. When a monosilicate layer is formed on the silicon oxide layer provided on the silicon carbide in this manner and then heated and sintered, the silicon oxide acts like an adhesive without the monosilicate layer disappearing, and the silicon carbide and the monosilicate layer Are joined well.

The bonding between silicon carbide and monosilicate is achieved by heating with a thin silicon oxide layer interposed between the silicon carbide layer and the monosilicate layer. The sintering temperature of silicon carbide is 2000 ° C. Since the temperature before and after the sintering is considerably higher than the sintering temperature of silicate or silicon oxide, the silicon carbide substrate to be joined is preferably a sintered body obtained by molding a powder containing silicon carbide and pre-sintering it.

In the case where the silicon oxide layer is formed by oxidizing the surface of the silicon carbide substrate, silicon carbide powder is molded and sintered in consideration of the fact that the substrate is likely to deteriorate in an oxidizing environment. It is preferable to use a dense silicon carbide sintered body obtained as a base material and form a silicon oxide layer thereon. The silicon carbide sintered body to be used does not need to be pure silicon carbide, and may contain impurities, and a sintered body prepared by using an additive such as a sintering aid can also be used. or,
Unreacted silicon may remain inside, such as a silicon carbide sintered body produced by a reaction sintering method. Alternatively, a composite material such as a fiber reinforced material may be used. The property of the generated silicon oxide layer changes depending on the oxidation conditions, the type and the amount of the auxiliary agent contained in the silicon carbide sintered body, and a silicon oxide layer such as a cristobalite phase or an amorphous phase is formed. When pure silicon carbide is heated and oxidized, a crystalline cristobalite phase silicon oxide layer is generated. When a small amount of impurities such as boron is present, an amorphous phase silicon oxide layer containing them is easily formed. Silicon carbide and monosilicate can be satisfactorily bonded to each other regardless of the phase of the silicon oxide layer.

The surface is oxidized by heating the above silicon carbide sintered body in an oxidizing atmosphere. As the heating temperature increases, the oxidation rate increases. However, the temperature at which the surface oxidation treatment is performed depends on the melting point of silicon oxide in the cristobalite phase (171
If the temperature exceeds 3 ° C.), a good layer is not formed due to foaming or the like,
In addition, deterioration due to rapid corrosion proceeds. In consideration of this, the heating temperature is preferably in the range of about 1350 to 1700 ° C. As the oxidation time increases, the thickness of the formed silicon oxide layer increases, and more specifically, the thickness of the generated silicon oxide layer is proportional to the half of the heating time. In order to satisfactorily join the silicon carbide layer and the monosilicate layer, the thickness of the silicon oxide layer to be formed is adjusted to 1 μm or more, preferably about 2 μm or more. Forming a thick silicon oxide layer requires a surface oxidation treatment at a high temperature and for a long time, and thus it is not economical to form a layer thicker than necessary. Further, it is not preferable in terms of the properties of the obtained laminated ceramics, so that the thickness is preferably about 100 μm or less. By heating at the above-described heating temperature for about 1 to 500 hours, a silicon oxide layer having a suitable thickness as described above can be obtained. If the oxidation treatment temperature is low and the treatment time is short, the formed silicon oxide layer does not reach a sufficient thickness, and cracks are formed inside the ceramic and at the bonding interface in the laminated ceramic obtained by the subsequent heat treatment with the monosilicate layer. Occurs. still,
When unreacted silicon remains inside the silicon carbide sintered body, the surface oxidation treatment must be performed at a heating temperature lower than the melting point of silicon (1400 ° C.), and a silicon oxide layer having a desired thickness is formed. In order to obtain, heating for a long time of about 500 hours is required. The oxidizing atmosphere for performing the surface oxidation treatment may be a pure oxygen atmosphere or an atmosphere containing a small amount of oxygen, such as air.

The silicon carbide substrate on which the silicon oxide layer is formed as described above is sintered by overlapping and heating the silicon oxide layer and the monosilicate layer so that they are in contact with each other.
The silicon oxide acts like an adhesive to obtain a laminated ceramic in which the silicon carbide substrate of the present invention and the monosilicate layer are joined.

As the monosilicate layer to be joined, a green compact formed by compressing a monosilicate powder into an appropriate shape by pressing or a rare earth oxide: RE ₂ O ₃ (where RE is Y, Yb , Er and Dy) and a silicon oxide powder in a ratio of 1: 1.
A green compact of a mixed powder having a monosilicate composition prepared so as to have a mixing ratio (molar ratio) can be used, and such a green compact is stacked on a silicon oxide layer of a silicon carbide substrate and heated. . When a mixed green compact of a rare earth oxide and silicon oxide is heated to the sintering temperature of monosilicate, sintering proceeds simultaneously with the formation of monosilicate, and as a result, the same as when using a monosilicate green compact It is. Alternatively, the monosilicate powder may be deposited on the silicon oxide layer of the silicon carbide base material by using a technique such as electrophoresis to laminate the monosilicate layer on the silicon oxide layer. Since the silicon carbide sintered body has conductivity, when the silicon carbide sintered body is immersed in a monosilicate suspension as a negative electrode and a DC voltage is applied, the monosilicate particles are electrophoretically effected, and the surface of the silicon carbide sintered body becomes To form a monosilicate layer. The formation of a monosilicate layer by electrophoresis is suitable for forming a thin layer with a thickness of several hundred μm, and the thickness of the silicon oxide layer to be formed can be easily controlled by adjusting the applied voltage and application time. it can. Further, even when the bonding interface is a curved surface, a uniform monosilicate layer can be formed, which is extremely useful.

The temperature of the heat treatment for bonding the silicon carbide substrate and the monosilicate layer with silicon oxide is about 1400 to 1400.
Preferably, the temperature is set to 1700 ° C. Hot press sintering in which pressure is applied simultaneously with heating may be performed. Part of the silicon oxide reacts or forms a solid solution with the silicon carbide and the monosilicate by heating, and acts as an adhesive on the silicon carbide layer and the monosilicate layer to join the two layers.

The monolithic ceramic layer obtained by the above-described method prevents the silicon carbide layer from being deteriorated by oxidation, and is a structural material having both high-temperature mechanical properties and oxidation resistance. In addition, since monosilicate easily forms a dense layer, the monosilicate layer suppresses a decrease in strength and results in a multilayer ceramic having higher resistance to oxidation.

The laminated ceramics thus bonded are stable laminates in which little residual stress is generated due to a difference in thermal expansion coefficient. However, in order to prevent the occurrence of cracks due to a rapid temperature change, cooling after heating must be performed. It is preferred to do it gently.

In the present invention, commonly used additives such as a sintering aid and a lubricant can be used in accordance with a general method, and a two-layer containing silicon carbide and disilicate as main components, respectively, can be used. Can be satisfactorily bonded.

[0026]

The present invention will be described below in more detail with reference to experimental examples.

[Production of Sintered Silicon Carbide] Silicon Carbide Powder 9
To 8 parts by weight, 1 part by weight of boron powder and 1 part by weight of carbon powder were added as sintering aids, wet-mixed with a ball mill, and dried to obtain a silicon carbide mixed powder. This powder is uniformly filled in a carbon mold, and the powder is placed in an argon atmosphere at 1 atm.
Hot press sintering was performed at a pressure of 40 MPa for 60 minutes while maintaining the temperature at 000 ° C., and the dimensions were 30 mm × 40 mm × 5.
mm of silicon carbide sintered body was obtained. This is ground and polished to 30mm
A silicon carbide piece of × 40 mm × 3 mm was obtained.

[Formation of Silicon Oxide Layer] An oxygen gas flow is passed through a horizontal annular furnace of an alumina furnace tube at a speed of 100 mm / min, and the silicon carbide pieces obtained above are arranged in the furnace and heated to form a surface. Was oxidized to produce a silicon carbide piece having a silicon oxide layer having a thickness of 1 to 200 μm. Since the thickness of the generated silicon oxide layer varies depending on the heating temperature and time,
The desired thickness was formed by adjusting the heating temperature and time.
In the above operation, the thickness of the silicon oxide layer is 15
Heat treatment at 00 ° C. × 1 hour resulted in 2 μm, 1550 ° C. × 3 hours 20 μm, and 1650 ° C. × 24 hours 200 μm.

[Preparation of Monosilicate Layer] For each rare earth element, a rare earth oxide powder: RE ₂ O ₃ (RE in the formula)
Represents a rare earth element selected from the group consisting of Y, Yb, Er and Dy) and silicon oxide (SiO ₂ ) powder in a ball mill such that the mixing ratio (molar ratio) becomes 1: 1. After drying, four kinds of silicate layers (Y ₂ SiO ₅ ,
A mixed powder for forming Yb ₂ SiO ₅ , Er ₂ SiO ₅ , Dy ₂ SiO ₅ ) was prepared. A part of each mixed powder is calcined in an argon atmosphere at 1300 to 1500 ° C. to form a monosilicate, and pulverized using a planetary ball mill to a fine powder having a particle size of 1 μm or less. I got

Each of the above-mentioned four kinds of mixed powder and four kinds of monosilicate powder were charged into a mold, and were press-molded by a cold press at a press pressure of 10 MPa to obtain eight kinds of compacts. These were used as a monosilicate layer in the following sample preparation.

[Preparation of Samples] Samples 1 to 20 were prepared according to Table 1.
Were prepared by the following operations.

(Samples 1 to 20) For each of Samples 1 to 20, a silicon carbide sintered body having a silicon oxide layer having a thickness shown in Table 1 was placed in a carbon mold, and a mixed powder having a monosilicate composition shown in Table 1 was obtained. Was pressed on a silicon oxide layer and heated at a press pressure of 30 MPa for 1 hour while heating to a heating temperature shown in Table 1 in an argon atmosphere, and then gradually cooled to room temperature. ~ 20 laminated ceramics were obtained.

[Evaluation] The conditions of the silicon carbide layer, the silicon oxide layer and the silicate layer of the laminated ceramics of Samples 1 to 20 were visually and microscopically examined by the following A to D.
The evaluation was made according to which of the above conditions. The results of the evaluation are shown in Table 1. (A) The silicon carbide layer, the silicon oxide layer and the monosilicate layer were satisfactorily joined, and no defects such as cracks were observed even under a microscope.

(B) Although microscopic cracks are observed in a part of the silicon carbide layer or the monosilicate layer when observed with a microscope, the layers are well bonded and completely integrated with each other.

(C) The silicon oxide layer disappeared and peeled off at the junction interface between the silicon carbide layer and the monosilicate layer.

(D) The silicon oxide layer was cracked or peeled off at the bonding interface of the silicon oxide layer and separated without being integrated.

[0037]

Table 1 Sample Monosilicate silicon oxide layer Heating temperature Evaluation Thickness (μm) (° C) _{) ------------------------------ 1 Y 2 SiO 5 1} 1550 C 2 Y 2 SiO 5 20 1550 A 3 Y 2 _{SiO 5 100 1550 B 4 Y 2} SiO 5 200 1550 D 5 Y 2 SiO 5 20 1300 D 6 Y 2 SiO 5 20 1750 C 7 Yb 2 SiO 5 1 1500 C 8 Yb 2 SiO 5 20 1500 A 9 Yb 2 SiO 5 _{200 1500 D 10 Yb 2 SiO 5} 20 1750 C 11 Er 2 SiO 5 1 1600 C 12 Er 2 SiO 5 20 1600 A 13 Er 2 SiO 5 100 1600 B 14 Er 2 SiO 5 200 1600 D 15 Er 2 Si _{5 20 1300 D 16 Er 2 SiO} 5 20 1750 C 17 Dy 2 SiO 5 1 1550 C 18 Dy 2 SiO 5 20 1550 A 19 Dy 2 SiO 5 200 1550 D 20 Dy 2 SiO 5 20 1750 C ------ −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− From the results of Samples 1 to 20, the bonding state between the silicon carbide layer and the monosilicate layer depends on the amount of silicon oxide. You can see that it changes. When the thickness of the silicon oxide layer is 1 μm or less as in Samples 1, 7, 11, and 17, a sufficient bonding action cannot be achieved by absorption into the monosilicate layer, and Samples 4, 9, 14, 1
When the thickness is 200 μm or more as in 9, peeling or cracking occurs due to the thermal behavior of the silicon oxide layer. From these, when the silicon oxide layer has a thickness of 2 to 100 μm, the bonding state becomes good.

When the heating temperature is as high as 1750 ° C. as in Samples 6, 10, 16, and 20, the remaining silicon oxide layer is reduced due to foaming of silicon oxide and promotion of absorption into the monosilicate layer, and sufficient bonding is achieved. do not do. Heating temperature is 1400-170
When the temperature is within the range of 0 ° C., good bonding is formed.

The same laminated ceramics as those of Samples 1 to 20 were prepared by using, as a monosilicate layer, a powder compact of a mixed powder of a rare earth oxide powder and a silicon oxide powder which was converted into a monosilicate by calcination. In this case, the same result as described above was obtained.

Further, using the laminated ceramic of Sample 2,
4mm × 3mm × 40 according to JIS-R1601
mm bending test pieces were prepared. At this time, the longitudinal direction of the bending test piece was made parallel to the bonding interface of the laminated ceramics, and a plurality of kinds of test pieces having different thicknesses of the monosilicate layer were prepared. Then, a fracture stress is applied to the test piece in an argon atmosphere at 1400 ° C. so that a tensile stress acts on the silicate layer side of the prepared bending test piece and the direction of crack propagation at the time of fracture is perpendicular to the lamination plane. A four-point bending test was performed. As a result, it was found that if the thickness of the monosilicate layer was within a certain range, the strength was not significantly reduced.

For samples 2, 8, 12, and 18,
When an oxidation resistance test was performed for 100 hours in an air atmosphere at 400 ° C., there was no change in composition or structure, and the composition was stable. Furthermore, it was stable in a 100-hour oxidation resistance test in an air atmosphere at 1500 ° C. As described above, by bonding a silicon carbide layer and a monosilicate layer via a silicon oxide layer firmly bonded to the silicon carbide layer, a material having excellent mechanical properties and oxidation resistance at high temperatures is provided. Is possible.

(Laminated Ceramics Made of Silicon Carbide Composite Substrate) An oxygen gas flow of 100 was passed through a horizontal annular furnace of an alumina furnace tube.
at a speed of 1400 ° C. at a flow rate of 1400 ° C.
The surface was oxidized by heating for 0 hour to form a silicon oxide film having a thickness of 20 μm. Thereafter, bonding treatment with each of the four types of monosilicate layers was performed in the same manner as in Samples 1 to 20, and the obtained laminated ceramics were similarly subjected to a four-point bending test at 1400 ° C. As in the case of No. 20, it was found that if the thickness of the monosilicate layer was within a certain range, the oxidation-resistant layer could be laminated without significantly lowering the strength. Further, the laminated ceramics are resistant to impact force and have high fracture resistance due to the effect of the composite fiber, and thus are optimal for structural members requiring reliability.

[0043]

As described above, according to the present invention,
A laminated ceramic having excellent strength and oxidation resistance at high temperatures can be obtained, and its industrial value is extremely large. Also,
The laminated ceramics obtained by the present invention is suitable as a material for a structural member used in a high-temperature oxidizing atmosphere due to its excellent heat resistance, and can supply high-quality mechanical parts and the like.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masareu Kato 1 Komukai Toshiba-cho, Saiwai-ku, Kawasaki-shi, Kanagawa Prefecture Toshiba R & D Center Co., Ltd. Japanese Unexamined Patent Publication No. Hei 7-277861 (JP, A) Japanese Unexamined Patent Publication No. Hei 10-87364 (JP, A) Japanese Unexamined Patent Publication No. Hei 10-87386 (JP, A) Japanese Unexamined Patent Publication No. Hei 11-12050 (JP, A) JP, A) JP-A-10-245288 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C04B 37/00 B32B 18/00 C04B 41/89

Claims (4)

(57) [Claims] 1. The method according to claim 1, further comprising: forming a first layer on the first layer containing silicon carbide.
A second layer containing silicon oxide having a chemical bonding property to the layer.
A step of forming a layer and a general formula: RE ₂ SiO ₅ (provided that
RE in the formula represents a rare earth element selected from the group consisting of Y, Yb, Er, and Dy), and heating by bringing a third layer containing a rare earth silicate compound represented by A method of manufacturing the laminated ceramics, comprising a step of integrating the first layer and the third layer. 2. A step of oxidizing the surface of the first layer containing silicon carbide to form a multilayer body of the second layer containing silicon oxide and the first layer, and a general formula: RE ₂ SiO ₅ (Wherein RE represents a rare earth element selected from the group consisting of Y, Yb, Er and Dy). The silicon oxide layer of the multilayer body is a third layer containing a rare earth silicate compound represented by A step of integrating the first layer and the third layer by contacting and heating the first layer and the third layer. 3. A multi-layer comprising the first layer and the second layer containing silicon oxide by heating the first layer containing silicon carbide in an oxidizing atmosphere to oxidize the surface of the first layer. A step of forming a layered body, and a step of forming a rare earth silicate compound represented by the general formula: RE ₂ SiO ₅ (wherein RE represents a rare earth element selected from the group consisting of Y, Yb, Er and Dy). A step of bringing the third layer into contact with the second layer of the multilayer body and heating the same to integrate the first layer and the third layer, thereby producing a multilayer ceramic. Method. 4. The first layer is a sintered body containing silicon carbide, and heat for oxidizing the surface of the first layer is 1350 to 1
The heating is performed at a temperature of 700 ° C. for 1 to 500 hours, and the heating for integrating the first layer and the third layer is performed at 1400 to 1700
The method for producing a laminated ceramic according to claim 3, wherein the method is performed at a temperature of ° C.