JPH0925178A - Ceramic-based fiber composite material and method for producing the same - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: The initial matrix fracture strength, crack growth resistance and fracture energy value are large, and the delamination strength can be improved, and a fibrous structure having a complicated shape can be formed relatively easily. Provided are a ceramic-based fiber composite material and a method for producing the same. In a ceramic-based fiber composite material in which a fiber structure is composited in a matrix made of ceramics, the fiber structure is braided by weaving a fiber bundle (2) formed by bundling a plurality of monofilaments as a braid. The braiding woven fabric 1 made of the woven fabric 1 has a fiber volume ratio (Vf) of 10 to 4 in the composite material.
It is characterized by being 0% by volume. Further, it is preferable that the braided yarns (fiber bundles) 2 constituting the braiding fabric 1 are arranged so as to be oblique to each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic-based fiber composite material and a method for producing the same, and more particularly to a highly reliable ceramic-based fiber having improved initial breaking strength characteristics by imparting a braided structure to fibers to be composited. TECHNICAL FIELD The present invention relates to a composite material and a manufacturing method thereof.

[0002]

2. Description of the Related Art In general, a ceramic sintered body has a small decrease in strength up to a high temperature, and has various properties such as hardness, electric insulation, abrasion resistance, heat resistance, corrosion resistance, and light weight as compared with conventional metal materials. Because of their excellent properties, they are used in a wide range of fields as electronic and structural materials such as heavy electrical equipment parts, aircraft parts, automobile parts, electronic equipment, precision machine parts, and semiconductor device materials.

However, the ceramics sintered body is weaker in tensile stress as compared with compressive stress, and has a drawback of so-called brittleness, in which fracture progresses at a stretch under this tensile stress. For this reason, in order to enable the application of ceramic parts to parts requiring high reliability, it is strongly required to increase the toughness and increase the fracture energy of the ceramic sintered body.

That is, gas turbine parts, aircraft parts,
Ceramic structural parts used for automobile parts are required to have high reliability in addition to heat resistance and high temperature strength.
In order to meet this demand, composite materials such as fibers, whiskers, plates and particles made of inorganic substances and metals are dispersed and compounded in a matrix sintered body to improve fracture toughness value, fracture energy value and thermal shock resistance. Researches for practical use of ceramic matrix composite (CMC) parts are being carried out by research institutions in Japan and abroad.

In particular, the ceramic base fiber composite material in which the ceramic fibers as described above are dispersed and composited in a matrix sintered body has a great effect of improving the fracture resistance. However, in order to increase the fracture resistance, it is necessary to compound a relatively large amount of fibers in the matrix. Further, in order to reduce the anisotropy of composite material characteristics, a preform formed by weaving ceramic fibers in a two-dimensional direction or a three-dimensional direction is used as a fiber structure.

When various structural parts are produced from the above ceramic-based fiber composite material, the initial matrix fracture strength of the composite material is large, the resistance to crack propagation is large, and the fracture energy is large. It is desirable to have

When the stress acting on the composite material is equal to or lower than the initial matrix breaking strength, it is in the elastic change region, so that the composite material is less likely to be damaged by cracks or the like. Further, under the above stress conditions, the excellent environment resistance of ceramics is sufficiently exhibited, and the deterioration of characteristics over time, which is accompanied by the progress of the damage initially generated in the material, cannot occur. Therefore, securing a large initial matrix fracture strength of the composite material is an extremely important item in the design of parts. Also, from the viewpoint of enhancing the reliability and damage tolerance of parts, increasing the fracture energy value of the composite material is also an extremely important item.

[0008]

However, in the conventional ceramic-based fiber composite material, it was practically impossible to satisfy both properties of high initial matrix fracture strength and large fracture energy at the same time. That is, the higher the initial matrix fracture strength, the smaller the resistance to crack growth, and the fracture energy tended to remain at a small value. On the contrary, in the case of a composite material having a large breaking energy, the initial matrix breaking strength tends to be low. In any case, a composite material that satisfies both the initial matrix fracture strength and the fracture energy cannot be obtained, which causes a problem that the target parts to which the composite material can be applied are limited to a narrow range.

Further, depending on the orientation direction of each fiber constituting the fiber structure, there is a drawback that the strength characteristics and the like of the composite material have anisotropy, and the characteristics of the entire component become unstable. In particular, in a composite material in which a plurality of fiber woven fabrics are laminated to form a fiber structure and the fiber structure is arranged in a ceramic matrix, there is also a problem that the interlaminar peel strength is extremely reduced.

On the other hand, the ceramic fibers constituting the fibrous structure are generally easily damaged by bending and rubbing, and the monofilaments constituting the fibers are cut or fluffed. There is a problem that it is difficult to form a preform (fiber structure) having a complicated shape such as.

The present invention has been made in order to solve the above problems, and has a large initial matrix fracture strength, crack propagation resistance and fracture energy value, and can improve delamination strength, and has a complex fiber structure. It is an object of the present invention to provide a ceramic-based fiber composite material capable of forming a body relatively easily and a method for producing the same.

[0012]

In order to achieve the above object, the present inventors have prepared a composite material by forming a fiber structure by various manufacturing methods, and the manufacturing method and structure of the fiber structure have a composite material. The strength characteristics, especially the influence on the initial matrix fracture strength and fracture energy were comparatively investigated. As a result, when a fiber bundle obtained by bundling filaments is woven by a braiding method to form a braiding fabric having a predetermined shape, when the braiding fabric is compounded into a ceramic matrix at a predetermined fiber volume ratio to form a composite material. The formation of a fibrous structure was extremely easy, and a composite material excellent in initial breaking strength was obtained for the first time.

Further, when a woven fabric element formed by weaving a fiber bundle as a braided yarn by braiding is further woven by a braiding method, a stitching method, an orthogonal three-dimensional weaving method, a plain weaving method or the like to form a fiber structure. In addition, the fiber arrangement becomes more complicated, and the crack growth resistance after the initial fracture of the matrix can be increased.

Further, by weaving the above-mentioned fabric elements to form a thicker fabric, it becomes easy to form a fibrous structure corresponding to the shape of the component, and the delamination strength of the composite material can be improved. That is, by using a thick woven fabric, it is possible to reduce the number of laminated woven fabrics in order to obtain a predetermined wall thickness required for a component. In particular, the fibrous structure can be formed with only one layer of the fabric.
It is inevitable that the delamination strength of the composite material is lower than the strength in other directions. However, by reducing the number of woven fabrics as described above, the number of fragile parts can be reduced.

Further, a braided woven fabric is formed by using a fiber bundle obtained by bundling a plurality of organic fibers and ceramic fibers, and only the organic fibers are carbonized to be used as a matrix-forming raw material. It is also easy to adjust the temperature, and it is possible to form a matrix sintered body in the part where the organic fiber was present, to form a dense matrix around the fiber, and to obtain a composite material with excellent fracture resistance characteristics. Was obtained. The present invention has been completed based on the above findings.

That is, the ceramic-based fiber composite material according to the present invention is a ceramic-based fiber composite material in which a fiber structure is composited in a matrix made of ceramics, and the fiber structure is a fiber bundle formed by bundling a plurality of monofilaments. The braided woven fabric is formed by weaving and is molded, and the fiber volume ratio (Vf) of the braiding woven fabric in the composite material is 10 to 40% by volume. Further, the fiber bundles constituting the braiding fabric are preferably arranged so as to be oblique to each other. Furthermore, the matrix is preferably formed of silicon carbide ceramics formed by reaction sintering. The braiding fabric includes a center yarn, and the Young's modulus of the center yarn can be greater than the Young's modulus of the braided yarn. Further, it is possible to make the diameter of the center yarn larger than the diameter of the braided yarn.

The fiber structure is composed of a plurality of fabric elements formed by weaving fiber bundles as braided yarns by braiding, and a braiding weave structure, a stitching structure, and a three-dimensional orthogonal weave structure using each fabric element as a raw material. It is characterized in that it is formed to have a weaving structure of any one of a structure, a plain weave structure and a satin weave structure.

Further, the fabric element may be composed of a flat braiding fabric formed into a strip or a round braiding fabric flattened into a sack.

Carbon (C) and boron nitride (BN)
It is advisable to form a sliding layer having a thickness of 0.1 to 5 μm, which is made of at least one of the above, on the filament surface by a CVD method, a PVD method or the like. Further, in order to suppress the reaction between the filament and the matrix material, it is preferable to provide a barrier layer made of a material different from that of the sliding layer so as to further cover the surface of the sliding layer. This barrier layer may be composed of at least one selected from silicon carbide (SiC), carbon (C), molybdenum (Mo), and molybdenum suicide (MoSi ₂ ).

Here, various ceramics sintered bodies can be used as the ceramics constituting the matrix of the ceramic-based fiber composite material, for example, silicon carbide (SiC), aluminum nitride (AlN), silicon nitride ( Si ₃ N ₄ ), sialon, boron nitride (BN)
Non-oxide ceramics sintered body such as alumina and alumina (Al
₂ O ₃ ), zirconia (ZrO ₂ ), titania (TiO
_2), mullite (3Al ₂ O ₃ · 2SiO _2), beryllia (BeO), cordierite, zircon, spinel (mixed MgAl ₂ O ₄₎ oxide-based ceramic materials such as one or two or more used To be done. In particular, in order to secure a large initial matrix fracture strength of the composite material and to secure an excellent environment resistance, it is desirable that the matrix is formed of a dense reaction sintered silicon carbide (RB-SiC) sintered body.

If necessary, the ceramic raw material powder for forming the above-mentioned sintered body contains yttrium oxide,
A sintering aid or additive such as alumina, cerium oxide, magnesium carbonate, calcium carbonate or silica is added. It is also possible to form the matrix by reaction sintering.

Further, the braiding fabric arranged in the matrix is compounded with a predetermined fiber volume ratio Vf in order to enhance the toughness of the composite material. The braided woven fabric is formed by weaving a fiber bundle formed by bundling 100 to 10,000 monofilaments as a braided yarn by a braiding method. The material of the monofilament forming the fiber bundle of the braiding fabric is not particularly limited, and the same ceramic fiber as the constituent material of the matrix can be used. Specific examples of such ceramic fibers include silicon carbide fibers (SiC,
Si—C—O, Si—Ti—C—O, etc.), SiC coated fiber (core wire is C, for example), alumina fiber, zirconia fiber, carbon fiber, boron fiber, silicon nitride fiber, Si ₃
N ₄ coated fiber (core wire is C, for example) and mullite (3A
_{l 2 O 3 · 2SiO 2 ~2Al} 2 O 3 · SiO 2) has fibers, it may use at least one selected from these.

The diameter and length of the fibers have a great influence on the arrangement of the fibers in the molded body, the volume fraction, and the strength characteristics of the composite material. In the present invention, the diameter is 3 to.
Use 150 μm continuous fibers. If the diameter is less than 3 μm, it will be near or below the particle size of the matrix,
With a thick fiber having a small composite effect and a diameter of more than 150 μm, stress due to a difference in thermal expansion easily occurs at the interface between the fiber and the matrix, and the matrix is easily cracked. In any case, the composite effect of the fiber Will be difficult to improve significantly.

The above ceramic fibers (monofilaments) are bundled into about 100 to 10,000 fibers to form a fiber bundle (yarn) having a predetermined thickness. Thereafter, the fiber bundle is woven as a braiding yarn by a braiding method or a braided fabric or It is a textile element.

FIG. 1 is a front view showing a state where a cylindrical braiding fabric (fiber structure) 1 is manufactured by applying a braiding method. A plurality of braided yarns (fiber bundles) 2 derived from the carrier of the braiding machine are wound vertically and horizontally so as to be wound around the surface of the mandrel (core) 3, whereby the braiding fabric 1 having a braided structure is obtained. It is formed.

FIG. 2 is a plan view showing an example of the structure of a braiding fabric, which is a fiber bundle 2a in the warp direction and a fiber bundle 2 in the weft direction.
b is woven at an intersection angle θ of about 60 degrees to form a braiding fabric 1a.

FIG. 3 is a plan view showing another structural example of the braiding fabric. In addition to the configuration shown in FIG. 2, a central yarn 4 extending in the vertical direction is woven into the braiding fabric 1b.
Are formed.

FIG. 4 is a plan view showing an example of the structure of the flat braided woven fabric 5. The flat braided woven fabric 5 is made into a plane by braiding the 9 fiber bundles 2 as braids. Has been formed. In order to form this flat-bladed braided fabric 5, at least five fiber bundles 2 are required as a braiding yarn.

FIG. 5 is a plan view showing another structural example of the flat braiding fabric 5a. This flat braiding fabric 5a is made by braiding 25 fiber bundles 2 and 12 central yarns 4. It is formed into a flat surface by processing.

FIG. 6 is a perspective view showing an example of the structure of the round striking braided fabric 6. This round striking braided fabric 6 is formed into a tubular shape by braiding the eight fiber bundles 2 as braids. It

The fibrous structure used in the present invention is formed by weaving a plurality of braiding fabrics prepared as described above as elements (fabric elements) into a two-dimensional structure or a three-dimensional structure. You may. 7 to 9 show fiber structures obtained by two-dimensionally weaving a textile element by braiding.

That is, the fiber structure 1d shown in FIG.
It is formed by weaving a plurality of textile elements 7 into a plain weave structure. The fibrous structure 1d has a structure in which the fabric elements 7, 7 in the vertical direction and the horizontal direction are alternately crossed one by one. Vertical and horizontal textile elements 7, 7
, The fiber structure 1d is tight and hard.

The fibrous structure 1e shown in FIG. 8 is formed by weaving a plurality of fabric elements 7 into a twill weave structure. In this fibrous structure 1e,
It has a structure in which two or more vertical or horizontal elements are juxtaposed and interlaced and combined with other elements. The fiber structure 1e having this structure is softer and easier to expand than the fiber structure 1d having a plain weave structure.

The fiber structure 1f shown in FIG. 9 is formed by weaving the fabric elements 7 and 7 into a satin weave structure. In this fibrous structure 1f, many textile elements 7 in the vertical direction or the horizontal direction are arranged in parallel, and have a structure in which intersecting portions are formed in some places. The fiber structure 1f having this structure has a softer property than the twill-woven fiber structure 1e.

The softness of the fibrous structure has a great influence on the breaking energy of the composite material, and the breaking energy value of the composite material tends to increase as the softness of the fibrous structure increases.

FIGS. 10 to 11 show three-dimensionally woven fiber structures of textile elements. That is, the fiber structure 1g shown in FIG. 10 uses a round-bladed braided fabric 6 as shown in FIG. 6 as a fabric element 7, and the fabric element 7 is formed by intersecting the X-axis direction, the Y-axis direction, and the Z-axis orthogonal to each other. And woven into a three-dimensional woven structure.

FIG. 11 is a perspective sectional view showing a ceramic-based fiber composite material 10 in which a fiber structure 1h having a stitching structure is composited in a ceramic matrix 8. The fibrous structure 1h of the composite material 10 includes, for example, the flat braided woven fabric 5 shown in FIG.
4 layers are laminated to form a laminated body, and this laminated body is sewn in the thickness direction by the stitching fiber bundle 9 to be integrally formed.

The conventional plain woven fabric corresponds to the case where the crossing angle θ between the braided yarn in the warp direction and the (fiber bundle) and the braided yarn in the weft direction is 90 degrees, and is limited to this intersecting angle. Therefore, the strength property with anisotropy is often a problem in the conventional ceramic-based fiber composite material in which a plain weave is composited.

However, as shown in FIGS. 2 to 3, the warp-direction fiber bundles 2a and the weft-direction fiber bundles 2b constituting the braiding fabric used in the present invention are 90 degrees apart from each other, as in the conventional plain fabric. Instead of being orthogonal with the intersection angle of
It is configured so as to be oblique to each other at an arbitrary intersection angle θ of about 10 to 170 degrees. Therefore, even if the hoop stress mainly acts in the radial direction of the braiding fabric 1 formed so that the fiber bundles 2 cross each other as shown in FIG. 1 or the principal stress acts in the axial direction, respectively. All diagonal fiber bundles 2 can be arranged to effectively counter this stress. Further, it can sufficiently withstand the stress generated when the matrix is formed in the braiding fabric 1 and the shrinkage stress generated when the matrix is fired, and can maintain the shape accuracy of the fabric itself and the composite material at a high level. it can.

In the present invention, since the fibrous structure (braiding woven fabric) or the woven fabric element is formed by the braiding method, the ceramic fiber can be easily cut even if it has a complicated shape without causing damage such as cutting or fluffing. A fibrous structure can be formed. That is, in the conventional plain woven fabric, the fiber is repeatedly bent at the reciprocating position of the weft shuttle and at the operating position of the warp yarn, and the number of times of rubbing the fibers is large. On the other hand, according to the braiding method, a continuous fiber bundle is wound around the outer circumference of the mandrel to form a woven fabric having a predetermined shape. Therefore, the fiber bundle is rubbed only once at the intersection. Therefore, there is less fiber cutting and fuzzing due to bending and rubbing of the fiber bundle,
A fiber structure having high reliability and good shape accuracy can be obtained.

Further, in the case where the braiding fabric is compounded with the matrix made of silicon carbide ceramics formed by the reaction sintering method, a plurality of organic fibers and ceramic fibers are bundled as a fiber bundle constituting the braiding fabric. The fiber volume ratio of the braiding fabric in the composite material can be easily adjusted by using the (bundled) fiber bundle as the braiding yarn or by using the braiding fabric in which the organic fiber and the ceramic fiber are mixed and woven. Can be adjusted to.

As the above-mentioned organic fibers, polyester yarns, polyethylene yarns, etc., which are easily decomposed and partially carbonized by a heating operation before the matrix synthesizing operation, are preferable, and continuous fibers having a diameter substantially the same as that of the ceramic fibers. Is preferred.

The organic fibers used as a secondary component as described above are carbonized by the heating operation before the matrix synthesis. Then, the carbonized organic fiber is used as a carbon source when synthesizing a silicon carbide (SiC) matrix by a reaction sintering method. As a result, the organic fibers that were in close contact with the ceramic fibers are converted into a SiC matrix, so that the matrix is sufficiently formed around the ceramic fibers. Therefore, it is possible to obtain a composite material having excellent strength characteristics because it is difficult to form a site where the ceramic fibers are bonded to each other or a void.

In order to increase the fracture resistance at the interface between the ceramic fiber and the matrix, it is necessary to provide a micro interface structure. Therefore, even when the fiber structure is formed by the braiding method, it is inappropriate to set the ceramic fiber diameter to a large value.
Usually, fine ceramic fibers are used. However, when weaving fine fibers to form a fiber structure having a predetermined wall thickness, a long braiding time is required, and the manufacturing efficiency of the composite material is likely to be reduced. In addition, the fiber structure itself becomes dense and the fiber volume ratio in the composite material tends to become excessive, so that the strength characteristics of the composite material tend to deteriorate.

Therefore, it is an effective means to use the ceramic fibers and the organic fibers as a mixture and to use the organic fibers as spacers for the ceramic fibers. After being carbonized as described above, the organic fiber is consumed as a carbon source for synthesizing the SiC matrix. As a result, a sufficient matrix is formed between the ceramic fibers, and the strength characteristics of the composite material can be significantly improved. The fiber volume ratio Vf of the fiber structure (braiding woven fabric) can be easily adjusted by changing the compounding ratio of the organic fiber and the ceramic fiber.

Further, as shown in FIG. 3, the fiber bundles 2 in the longitudinal direction
By using the braiding fabric 1b provided with the central yarn 4 so as to connect the respective intersections of the fiber bundle 2b in the direction a and the weft direction, the fabric characteristics in the direction in which the central yarn 4 is provided can be adjusted. In particular, since the central yarn 4 has almost no bending, its Young's modulus can be set to be larger than that of the braiding yarns 2a and 2b, and the strength characteristics in the direction in which the central yarn 4 is arranged can be increased. Further, even when an external force is applied during impregnation of the matrix raw material slurry, the deformation is small, and the shape accuracy of the braiding fabric can be kept high.

Similarly, since the central yarn 4 has almost no bending, its fiber diameter can be set larger than that of the braiding yarns 2a and 2b. Therefore, the effect of preventing the progress of cracks and destruction is enhanced, and a composite material having a large crack propagation resistance can be obtained. In addition, a function as a spacer between the fibers is exhibited, and there is an advantage that a woven fabric having a predetermined thickness can be efficiently manufactured with a small number of fiber bundles. The function of the central yarn 4 as a spacer is also effective in adjusting the fiber volume ratio.

When the fiber woven fabric is formed by using the braiding method as described above, the crossing angle θ of each braiding yarn and the presence or absence of the central yarn 4 can be appropriately selected and easily controlled. Therefore, it is possible to arrange the fibers according to the application and the required characteristics of the component formed of the composite material.

Since the central yarn 4 is arranged at a portion where the bending is small such as an intersection of fiber bundles, even a fiber having a high Young's modulus or a fiber having a large diameter is less likely to be broken. The center yarn 4 is effective in improving the strength of the fibrous structure itself as described above, and at the same time, in improving the mechanical strength of the entire composite material.

In order to prevent the reaction between the ceramic fiber and the matrix, or to improve the slippage at the interface between the two, a thickness of 0.1 on the surface of the ceramic fiber.
It is preferable to form a slip layer having a thickness of about 5 μm. This sliding layer is formed by coating the surface of the fiber with carbon (C) or boron nitride (BN).

By the above-mentioned sliding layer, ceramic fibers and
The strength between the matrix and the matrix is optimized, and due to this optimum strength, the holding strength after initial fracture can be kept high, and a composite material having a high toughness value can be obtained.

The braiding woven fabric (fibrous structure) formed by the braiding method is combined with the matrix at a ratio of 10% or more in fiber volume ratio (Vf) with respect to the whole composite material. However, when the fiber volume ratio is over 40%, it becomes difficult to uniformly arrange the matrix around each fiber constituting the woven fabric, and the strength characteristics of the composite material are rapidly deteriorated due to the occurrence of defects such as voids. Will end up. Therefore, the preferable volume ratio at which the combined effect appears is 1
It is in the range of 0 to 40% by volume.

The ceramic-based fiber composite material in which the braiding woven fabric is arranged in the matrix is manufactured, for example, as follows. That is, a fiber bundle formed by bundling a plurality of monofilaments is woven by a braiding method to form a fiber structure having a predetermined shape, and the obtained fiber structure is impregnated with a matrix raw material slurry to obtain a molded body,
The obtained molded body is degreased and dried, and then sintered to integrally manufacture the matrix and the fiber structure.

On the other hand, when a fiber bundle obtained by bundling organic fibers and ceramic fibers is used as the fiber bundle, and when the matrix is formed by the reaction sintering method, the molded body obtained by the above manufacturing method is used as an inert gas. It is manufactured by heating in an atmosphere to carbonize the organic fibers and then impregnating a molded body with molten silicon, and reacting and sintering the silicon and the carbon component to form a matrix made of silicon carbide.

According to the ceramic-based fiber composite material and the method for producing the same according to the above-described structure, since the fiber structure (braiding woven fabric) is formed by the braiding method, damage such as cutting of ceramic fibers and fuzzing occurs. The fiber structure can be easily formed without complicated shapes.

Since the braiding fabric used in the present invention has a braid structure and the crossing angle of the braiding yarn can be arbitrarily controlled, the fibers can be effectively compounded in the principal stress direction generated in the component. is there. Therefore, a composite material part using this braiding fabric has high reliability.

By configuring the braided woven fabric so that the warp-direction fiber bundles and the weft-direction fiber bundles cross each other obliquely, even when an external force is applied to the braided fabric, The fiber bundle exerts an action against this external force, and the deformation of the braiding fabric can be effectively prevented. Therefore, it can withstand the stress generated when the matrix raw material slurry is impregnated into the braiding fabric, and can sufficiently withstand the shrinkage stress generated during the firing of the matrix, which maintains the shape accuracy of the fabric itself and the composite material with high accuracy. can do.

Further, in the case where a braiding woven fabric is compounded with a matrix made of silicon carbide ceramics formed by the reaction sintering method, a plurality of organic fibers and ceramic fibers are bundled as a fiber bundle constituting the braiding woven fabric. By using the (bundled) fiber bundle, the fiber volume fraction of the braiding woven fabric in the composite material can be easily adjusted.

The organic fibers used as described above are carbonized by a heating operation before the synthesis of the matrix and further used as a carbon source when synthesizing a silicon carbide (SiC) matrix by the reaction sintering method. As a result, the organic fibers that were in close contact with the ceramic fibers are converted into a SiC matrix, so that the matrix is sufficiently formed around the ceramic fibers. Therefore, it is possible to obtain a composite material having excellent strength characteristics because it is difficult to form a site where the ceramic fibers are bonded to each other or a void.

[0060]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the accompanying drawings.

Example 1 An SiC-based ceramic continuous fiber having a diameter of 14 μm (trade name: Hynicalon, manufactured by Nippon Carbon Co., Ltd.) was prepared as a monofilament for Example 1. A slide layer made of boron nitride (BN) having a thickness of 0.6 μm was formed on the surface of the SiC ceramic continuous fiber by the CVD method. Further, the outside of the sliding layer is coated with silicon carbide (SiC) by the CVD method to have a thickness of 0.5 μm.
m barrier layer was formed.

Next, a polyester fiber having the same diameter as the above-mentioned SiC ceramic continuous fiber on which the sliding layer and the barrier layer have been formed is prepared.
C continuous fibers were mixed at a ratio of 1: 1 to prepare a fiber bundle (yarn) composed of a total of 1000 fibers. Further, the obtained fiber bundle was loaded into a braiding machine having 48 carriers and, as shown in FIG. 12, a fiber bundle 2c was formed around a cylindrical core (mandrel) 3a having an outer diameter of 100 mm at a crossing angle of 60 degrees. By winding, the outer diameter is 110 mm × the inner diameter is 1
Fiber structure (blading woven fabric) 1c for Example 1 having a braid structure of 7 layers, which is 00 mm × 100 mm in length
Were prepared in large numbers.

On the other hand, 70% by weight of SiC powder having a central particle size of 1 to 3 μm as an aggregate, 10% by weight of carbon black as a carbon source, and 15% by weight of a water-soluble phenol resin,
A solid mixture consisting of 5% by weight of polycarbosilane was prepared, and 50% by weight of this solid mixture, 49% by weight of water and 1% by weight of a surfactant were uniformly mixed to prepare a matrix raw material slurry. .

Next, the braiding woven fabric is set in a porous resin molding die, and the matrix raw material slurry is pressure-impregnated into each of the braiding woven fabrics using a pressure casting method to contain each fiber. It was a ceramic compact. As shown in Table 1, the fiber volume ratio (Vf) in the densified composite material sintered body was set to 32%.

Next, the prepared fiber-containing ceramic compact is dried and further heated in an inert gas (Ar gas) at a temperature of 10
By heating at 00 ° C. for 5 hours, the polyester fibers and the phenol resin contained in the molded body were carbonized and polycarbosilane was thermally decomposed. Thereafter, the fiber-containing ceramics compact was placed in an alumina board filled with 1.2 times as much Si powder as necessary for silicification of the fiber-containing ceramics compact, and the firing furnace was adjusted to a vacuum state. By heating at 1450 ° C. for 5 hours, the fiber-containing ceramic compact is reacted and sintered while being impregnated with molten Si to synthesize a dense matrix of SiC sintered compact. Cylindrical Si according to Example 1 as shown in 13
A C-based fiber composite material 10a was prepared.

The composite material 10a according to the first embodiment is S
It has a structure in which a braiding woven fabric 1c made of SiC continuous fibers is compounded in a matrix 8a made of an iC reaction sintered body.

The density of the obtained cylindrical composite material was 2.
The density was as high as 8 g / cm ³ . Also, when a plate-shaped test piece was cut out from the composite material and the internal structure was observed in detail,
In each case, a matrix made of SiC was uniformly and densely formed around the ceramic fibers. The three-point bending strength of the cut out test piece is 280 to 310 MPa.
It was found that even if cracks occurred, a fracture mode that did not reach complete fracture at once was observed, and that the metastable fracture behavior required for composite materials was obtained.

Example 2 An example was carried out in the same manner as in Example 1 except that a fiber bundle in which continuous fibers of SiC ceramics and polyester fibers were mixed at a ratio of 1: 3 was used, and the fiber volume ratio was 12%. Two
A SiC-based fiber composite material according to 1. was prepared.

Example 3 A braided woven fabric obtained by continuously weaving SiC ceramic continuous fibers and polyester fibers in a ratio of 1: 1/3 was used, and the same process as in Example 1 was performed except that the fiber volume ratio was 38%. A SiC-based fiber composite material according to Example 3 was prepared.

Comparative Example 1 The same procedure as in Example 1 was carried out except that a fiber bundle prepared by mixing SiC ceramic continuous fiber and polyester fiber in a ratio of 1: 6 was used, while the fiber volume ratio was set to be too small at 5%. A SiC-based fiber composite material according to Comparative Example 1 was prepared.

Comparative Example 2 Same as Example 1 except that a braided woven fabric in which SiC ceramic continuous fiber and polyester fiber were mixed and woven at a ratio of 1: 1 was used, while the fiber volume ratio was set to 47% which was excessive. Was treated to prepare a SiC-based fiber composite material according to Comparative Example 2.

Example 4 SiC ceramic continuous fiber having a diameter of 14 μm (trade name:
Hynicalon, manufactured by Nippon Carbon Co., Ltd.) was prepared as a monofilament for Example 4. A thickness of 0.6 is formed on the surface of this SiC ceramic continuous fiber by the CVD method.
A sliding layer made of μm boron nitride (BN) was formed. A fiber bundle (yarn) obtained by bundling 500 SiC ceramic continuous fibers was prepared as a braided yarn. The Young's modulus of the fiber bundle was 270 PGa.

On the other hand, a surface-modified layer containing BN having a thickness of 3 was formed on the monofilament surface of a SiC ceramic continuous fiber (trade name: SCS-9, manufactured by Textron Co.) having a diameter of 80 μm.
What was formed by μm was prepared as a central thread. The Young's modulus of the central yarn was 374 GPa.

Next, the braided yarn and the central yarn are loaded into a braiding machine having 48 carriers, and the braided yarn is wound around the outer periphery of a cylindrical core having an outer diameter of 100 mm as shown in FIG. By arranging the central thread, the outer diameter 110
A large number of fiber structures (blading woven fabrics) for Example 4 having a 7-layer braided structure having a size of mm × inner diameter 100 mm × length 100 mm were prepared.

Next, the braiding fabric was set in a porous resin molding die, and the matrix raw material slurry prepared in Example 1 was pressure-impregnated into the braiding fabric using a pressure casting method. As a result, each fiber-containing ceramic compact was obtained. As shown in Table 1, the impregnation amount of the raw material slurry was set so that the fiber volume ratio (Vf) in the densified composite material sintered body was 35%.

Next, after drying the prepared fiber-containing ceramic compact, the above-mentioned fiber-containing ceramic compact was filled in an alumina board filled with 1.2 times as much powder Si as necessary for silicification of the fiber-containing ceramic compact. In a firing furnace in which the ceramic molded body is placed and adjusted to a vacuum state, 1450
According to Example 4, the fiber-containing ceramics compact was subjected to reaction sintering while being impregnated with molten Si by heating at a temperature of ° C for 5 hours to synthesize a dense matrix of SiC sintered compact. A cylindrical SiC-based fiber composite material was prepared.

The density of the obtained cylindrical composite material was 2.
The density was as high as 8 g / cm ³ . Also, when a plate-shaped test piece was cut out from the composite material and the internal structure was observed in detail,
In each case, a matrix made of SiC was uniformly and densely formed around the ceramic fibers. Further, the three-point bending strength of the test piece cut out so that the central yarn is parallel to the pulling direction shows a high value of 340 to 410 MPa, and a fracture mode is observed in which even if a crack occurs, it does not reach a complete break at once. It was found that the metastable fracture behavior required for composite materials was obtained.

Example 5 An example was carried out in the same manner as in Example 4 except that a fiber bundle in which continuous fibers of SiC ceramics and polyester fiber were mixed at a ratio of 1: 1 was used, and the fiber volume ratio was 16%. 5
A SiC-based fiber composite material according to 1. was prepared.

Comparative Example 3 A treatment was performed in the same manner as in Example 4 except that a fiber bundle in which continuous fibers of SiC ceramics and polyester fiber were mixed at a ratio of 1: 3 was used, while the fiber volume ratio was set to be too small at 6%. A SiC-based fiber composite material according to Comparative Example 3 was prepared.

Comparative Example 4 A fiber bundle (yarn) made of the SiC ceramic continuous fibers prepared in Example 4 was plain-woven at a weaving density of 12 yarns per inch to form a cloth, and the cloth thus obtained was laminated to form a conventional cloth. Of the fiber preform. The subsequent conditions for forming the matrix were set in the same manner as in Example 4, and the fiber preform and the matrix were compounded to prepare a SiC-based fiber composite material according to Comparative Example 4.

In order to evaluate the fracture characteristics of the composite materials of Examples 1 to 5 and Comparative Examples 1 to 4 prepared as described above, bending test pieces were cut out from each composite material and subjected to room temperature (R
The density, initial breaking strength and breaking energy at T: 25 ° C.) were measured. Here, the fracture energy value of each test piece was calculated by integrating the fracture energy from the shape of the stress-strain curve, setting the case of Comparative Example 1 as the reference value 1, and calculating the magnification against that reference value and displaying each as a relative value. . The measurement evaluation results are shown in Table 1 below.

[0082]

[Table 1]

As is clear from the results shown in Table 1, the braided woven fabric was used as the fiber structure, and the fiber volume ratio (Vf) of the braided woven fabric was set in the range of 12 to 38%. According to the SiC-based fiber composite material according to each example, a composite material having high initial fracture strength and fracture energy value and high reliability is obtained. In particular, Example 4 using a braiding fabric having a central yarn
It was also proved that in the composite materials of ~ 5, the strength of the fiber structure itself was significantly increased, so that the initial fracture strength of the composite material was remarkably improved.

On the other hand, Comparative Example 1 in which the fiber volume ratio is too small
It was found that the composite material of 3 had a small fracture energy value and was likely to cause brittle fracture even if a braiding fabric was used. In addition, it was confirmed that the composite material of Comparative Example 2 in which the fiber volume ratio was excessively large did not sufficiently form the matrix around the fibers, and thus the initial breaking strength was significantly reduced. Further, in the composite material of Comparative Example 4 in which the preform in which the plain weave cloth is laminated is used as the fiber structure, the fiber itself has the strength anisotropy even if the fiber volume ratio is set as high as 30%. It was confirmed that the fracture resistance of the composite material as a whole was insufficient. Further, in Comparative Example 4, it was confirmed that the fibers were frequently cut, and it was necessary to reexamine the weaving method of the cloth and the like in order to further improve the productivity.

Example 6 Continuous SiC-based ceramic fibers having a diameter of 14 μm (trade name: Hynicalon, manufactured by Nippon Carbon Co., Ltd.) were prepared as monofilaments for Example 6. A slip layer made of boron nitride (BN) having a thickness of 0.4 μm was formed on the surface of the SiC ceramic continuous fiber by the CVD method. Further, the outside of the sliding layer is coated with silicon carbide (SiC) by the CVD method to have a thickness of 0.4 μm.
m barrier layer was formed.

Next, a fiber bundle (yarn) was prepared by bundling 500 pieces of the above-mentioned SiC ceramic continuous fibers on which the sliding layer and the barrier layer were formed. Further, using the obtained fiber bundle, a round braiding fabric comprising 24 braided yarns and 12 central yarns was prepared. Further, the obtained round-bladed braided fabric was crushed into a sack-like band to obtain a fabric element. Furthermore, using this textile element as a braiding thread, an outer diameter of 100
A thick braiding fabric consisting of 24 braided yarns (zero center yarn) was prepared by braiding the fabric elements around the outer periphery of a mandrel (mm x height 100 mm). Furthermore, by stacking three layers of this thick braiding fabric, the outer diameter is 110 mm, the inner diameter is 100 mm, and the length is 1.
A fibrous structure for Example 6 having a size of 00 mm × 5 mm was prepared.

On the other hand, a solid mixture consisting of 70% by weight of SiC powder having a central particle diameter of 1 to 3 μm as an aggregate and 30% by weight of carbon black as a carbon source was prepared. Pure water 47% by weight and surfactant 3
% By weight were uniformly mixed to prepare a matrix raw material slurry.

Next, the fiber structure is set in a porous resin molding die, and the matrix raw material slurry is pressure-impregnated into the fiber structure using a pressure casting method to mold each fiber-containing ceramic. I made it a body. In addition, as shown in Table 2, the fiber volume ratio (Vf) in the densified composite material sintered body was set to be 27%.

Next, after drying the prepared fiber-containing ceramic molded body, the fiber-containing ceramic molded body was filled with 1.2 times the amount of Si necessary for silicidation of the fiber-containing ceramic molded body in an alumina board filled with the above-mentioned fiber-containing material. In a firing furnace in which the ceramic molded body is placed and adjusted to a vacuum state, 143
By heating for 5 hours at a temperature of 0 ° C., while impregnating with molten Si, the above-mentioned fiber-containing ceramic compact is reaction-sintered to synthesize a dense matrix made of a SiC sintered body. Such a cylindrical SiC-based fiber composite material was prepared.

The composite material according to Example 6 has a structure in which a fiber structure made of SiC continuous fibers is compounded in a matrix made of a SiC reaction sintered body.

The density of the obtained cylindrical composite material was 3.
It had a high density of 0 g / cm ³ . Also, when a plate-shaped test piece was cut out from the composite material and the internal structure was observed in detail,
In each case, a matrix made of SiC was uniformly and densely formed around the ceramic fibers. The three-point bending strength of the cut out test piece is 190 to 430 MPa.
It was found that even if cracks occurred, a fracture mode that did not reach complete fracture at once was observed, and that the metastable fracture behavior required for composite materials was obtained.

Example 7 A continuous SiC-based ceramic fiber having a diameter of 14 μm (trade name: Hynicalon, manufactured by Nippon Carbon Co., Ltd.) was prepared as a monofilament for Example 7. A slip layer made of boron nitride (BN) having a thickness of 0.4 μm was formed on the surface of the SiC ceramic continuous fiber by the CVD method.

Next, 500 continuous fibers of the above-mentioned SiC ceramics having a sliding layer were bundled to prepare a fiber bundle (yarn). Further, the obtained fiber bundle was used to prepare a round-braiding woven fabric composed of 6 braided yarns and 24 central yarns. Further, the obtained round-bladed braided fabric was crushed into a sack-like band to obtain a fabric element. Furthermore, by using this woven element as a braiding thread, the outer diameter is 100 mm and the height is 100 mm.
A thick braided fabric consisting of 24 braided yarns (zero in the central yarn) was prepared by braiding the weaving elements around the outer periphery of the mandrel. Furthermore, by stacking 3 layers of this thick braiding fabric,
Outer diameter 110 mm x inner diameter 100 mm x length 100 mm x thickness 5 mm
A fibrous structure for Example 7 was prepared.

Next, the above fibrous structure was set in a porous resin molding die, and the matrix raw material slurry prepared in Example 6 was pressure-impregnated into the fibrous structure using a pressure casting method to form fibers. A ceramic containing body was prepared. In addition, as shown in Table 2, the fiber volume ratio (Vf) in the densified composite material sintered body was set to be 27%.

Next, after drying the prepared fiber-containing ceramic compact, the above-mentioned fiber-containing ceramic compact was filled in an alumina board filled with 1.2 times as much powder Si as necessary for silicification of the fiber-containing ceramic compact. In a firing furnace in which the ceramic molded body is placed and adjusted to a vacuum state, 143
By heating at 0 ° C. for 5 hours to impregnate molten Si with the fiber-containing ceramic compact, the fiber-containing ceramic compact is reaction-sintered to synthesize a dense matrix of SiC sintered compact. Such a cylindrical SiC-based fiber composite material was prepared.

The composite material according to Example 7 has a structure in which a fiber structure made of SiC continuous fibers is compounded in a matrix made of a SiC reaction sintered body.

The density of the obtained cylindrical composite material was 3.
It had a high density of 0 g / cm ³ . Also, when a plate-shaped test piece was cut out from the composite material and the internal structure was observed in detail,
In each case, a matrix made of SiC was uniformly and densely formed around the ceramic fibers. The three-point bending strength of the cut out test piece is 200 to 460 MPa.
It was found that even if cracks occurred, a fracture mode that did not reach complete fracture at once was observed, and that the metastable fracture behavior required for composite materials was obtained.

Comparative Example 5 In the same manner as in Example 6, 500 continuous SiC-based ceramic fibers having a sliding layer made of boron nitride (BN) having a thickness of 0.4 μm formed on the surface of the monofilament by the CVD method were bundled to form a fiber bundle ( Yarn) was prepared. Weaving this fiber bundle to a conventional plain weave structure to produce a plain weave,
Further, it was cut into strips.

Next, by winding 12 layers of the above band-shaped plain weave around the outer periphery of the core (mandrel) having an outer diameter of 100 mm and a height of 100 mm, an outer diameter of 110 mm × an inner diameter of 100 mm × a length of 100 mm × a thickness of 5 mm. A cylindrical fiber structure was prepared.

Thereafter, in the same manner as in Example 6, the matrix raw material slurry was pressure-impregnated into the above fibrous structure to obtain a molded body, and the molded body was dried and then impregnated with molten Si.
The SiC-based fiber composite material according to Comparative Example 5 was manufactured by reacting and sintering the compact.

Bending test pieces were cut out from each of the composite materials of Examples 6 to 7 and Comparative Example 5 produced in this way, and the density at room temperature (25 ° C.), the initial matrix fracture strength and the maximum strength by a three-point bending test were measured. Further, the fracture energy and the layer-direction shear peel strength of each composite material were measured from the load-displacement curve obtained by the three-point bending test. The measurement results are shown in Table 2 below.

[0102]

[Table 2]

As is clear from the results shown in Table 2 above,
The composite material of each example using the fiber structure formed by further braiding the textile element obtained by braiding weave is the same as the composite material of Comparative Example 5 using the conventional plain weave structure fiber structure. By comparison, it was found that the effective fracture energy is improved more than twice because the initial matrix fracture strength is high and the crack propagation resistance is high. The interlaminar shear peel strength is 3
It was proved that the strength could be improved more than double and the maximum strength was more than double, and excellent strength characteristics and durability could be obtained.

In each of the above examples, the case where the reaction-sintered SiC matrix is formed as the ceramic matrix is exemplified, but Si ₃ N ₄ , Sialon, AlN, Al ₂ O ₃ , Zr is used as the matrix.
Similar complex effects were obtained when O ₂ , SiO ₂ , mullite and spinel were formed.

[0105]

As described above, according to the ceramic-based fiber composite material and the method for producing the same according to the present invention, the fiber structure (braiding woven fabric) is produced by the braiding method.
Since it is formed, the fibrous structure can be easily formed even in a complicated shape without causing damage such as cutting or fluffing of the ceramic fiber.

Further, since the braiding fabric used in the present invention has a braid structure and the crossing angle of the braiding yarn can be arbitrarily controlled, it is possible to effectively combine the fibers in the stress direction generated in the component. . Therefore, a composite material part using this braiding fabric has high reliability.

By configuring the braided woven fabric so that the warp direction fiber bundles and the weft direction fiber bundles cross each other, even when an external force acts on the braided fabric, The fiber bundle exerts an action against this external force, and the deformation of the braiding fabric can be effectively prevented. Therefore, it can withstand the stress generated when the matrix raw material slurry is impregnated into the braiding fabric, and can sufficiently withstand the shrinkage stress generated during the firing of the matrix, which maintains the shape accuracy of the fabric itself and the composite material with high accuracy. can do.

When a braiding woven fabric is compounded with a matrix made of silicon carbide ceramics formed by the reaction sintering method, a plurality of organic fibers and ceramic fibers are bundled as a fiber bundle constituting the braiding woven fabric. By using the (bundled) fiber bundle, the fiber volume fraction of the braiding woven fabric in the composite material can be easily adjusted.

The organic fiber used as described above is carbonized by a heating operation before matrix synthesis, and is further used as a carbon source when synthesizing a silicon carbide (SiC) matrix by a reaction sintering method. As a result, the organic fibers that were in close contact with the ceramic fibers are converted into a SiC matrix, so that the matrix is sufficiently formed around the ceramic fibers. Therefore, it is difficult to form a site where the ceramic fibers are bonded to each other, and a composite material having excellent strength characteristics can be obtained.

[Brief description of drawings]

FIG. 1 is a front view showing a state in which a cylindrical braiding fabric is being manufactured.

FIG. 2 is a plan view showing one embodiment of a braiding fabric.

FIG. 3 is a plan view showing another embodiment of the braiding fabric.

FIG. 4 is a plan view showing a configuration example of a flat-bladed braiding fabric.

FIG. 5 is a plan view showing another example of the configuration of the flat-laminated braiding fabric.

FIG. 6 is a perspective view showing an example of the configuration of a round braiding fabric.

FIG. 7 is a diagram showing a structure of a fiber structure in which a woven fabric element formed by braiding is further woven so as to have a plain weave structure.

FIG. 8 is a diagram showing the structure of a fiber structure in which a woven element formed by braiding is further woven to have a twill structure.

FIG. 9 is a diagram showing a structure of a fiber structure in which a woven element formed by braiding is further woven to have a satin weave structure.

FIG. 10 is a perspective view showing the structure of a fiber structure obtained by further weaving a woven fabric element by braiding into a three-dimensional structure.

FIG. 11 is a perspective cross-sectional view showing a structure of a ceramic-based fiber composite material in which a fiber structure having a stitching structure is composited in a ceramic matrix.

FIG. 12 is a perspective view showing the shape of the braiding fabric used in the example.

FIG. 13 is a partially cutaway perspective view showing a cylindrical SiC-based fiber composite material according to an example.

[Explanation of symbols]

1,1a, 1b, 1c, 1d, 1e, 1f, 1g Braiding woven fabric (fiber structure) 2,2a, 2b, 2c Braided yarn (fiber bundle) 3,3a Mandrel (core) 4 Central yarn 5,5a Flat braiding fabric 6 Round braiding fabric 7 Textile element 8,8a Ceramics matrix 9 Stitching fiber bundle 10,10a Ceramics base fiber composite material

Front page continuation (72) Inventor Noboru Ajiji 2-4 Suehiro-cho, Tsurumi-ku, Yokohama-shi, Kanagawa Toshiba Corporation (72) Inventor Yoshinori Hayakawa 7-1 Nisshin-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Toshiba Electronics Engineering Co., Ltd.

Claims (14)

[Claims] 1. A ceramic-based fiber composite material in which a fibrous structure is composited in a matrix made of ceramics, wherein the fibrous structure is a braid formed by weaving a fiber bundle formed by bundling a plurality of monofilaments as a braid. A ceramic-based fiber composite material comprising a woven fabric, wherein the braiding woven fabric has a fiber volume ratio (Vf) of 10 to 40% by volume in the composite material. 2. The ceramic-based fiber composite material according to claim 1, wherein the fiber bundles constituting the braiding fabric are arranged so as to cross each other. 3. The ceramic-based fiber composite material according to claim 1, wherein the matrix is a silicon carbide ceramic formed by reaction sintering. 4. The ceramic-based fiber composite material according to claim 1, wherein the braiding fabric includes a central yarn, and the Young's modulus of the central yarn is higher than the Young's modulus of the braided yarn. 5. The ceramic-based fiber composite material according to claim 4, wherein the diameter of the central yarn is larger than the diameter of the braided yarn. 6. The fiber structure comprises a plurality of fabric elements formed by weaving fiber bundles as braided yarns by braiding, and a braiding weave structure, a stitching structure, and a three-dimensional orthogonal structure using each fabric element as a material. The ceramic-based fiber composite material according to claim 1, wherein the ceramic-based fiber composite material is formed to have any one of a weaving structure, a plain weave structure, and a satin weave structure. 7. The ceramic-based fiber composite material according to claim 6, wherein the woven element is a flat braided woven fabric formed in a strip shape. 8. The ceramic-based fiber composite material according to claim 6, wherein the woven fabric element is a round-blading woven fabric which is flattened into a bag-like shape. 9. The sliding layer having a thickness of 0.1 to 5 μm made of at least one of carbon (C) and boron nitride (BN) is formed on the surface of the monofilament. Ceramic-based fiber composite material. 10. A monofilament surface having a sliding layer of at least one of carbon (C) and boron nitride (BN) and having a thickness of 0.1 to 5 μm, and silicon carbide so as to cover the outside of this sliding layer. (SiC), carbon (C), molybdenum (Mo) and molybdenum silicide (M
7. A ceramic-based fiber composite material according to claim 1, wherein a barrier layer made of at least one selected from oSi ₂ ) is formed. 11. A fiber bundle formed by bundling a plurality of monofilaments is woven by a braiding method to form a fiber structure having a predetermined shape, and the obtained fiber structure is impregnated with a matrix raw material slurry to obtain a molded body, A method for producing a ceramic-based fiber composite material, characterized in that the obtained molded body is degreased and dried, and then sintered to integrate the matrix and the fiber structure. 12. A fiber bundle formed by bundling a plurality of monofilaments is woven by a braiding method to form a plurality of fabric elements, and each fabric element is used as a material for a braiding weave structure, a stitching structure, and an orthogonal three-dimensional weave structure. , Forming a fibrous structure of a predetermined shape having either a plain weave structure or a satin weaving structure, impregnating the obtained fibrous structure with a matrix raw material slurry to form a formed body, and degreasing the obtained formed body. A method for producing a ceramic-based fiber composite material, which comprises drying and then sintering to integrate a matrix and a fiber structure. 13. A fiber bundle obtained by bundling organic fibers and ceramic fibers as a fiber bundle is used, and the molded body is heated in an inert gas atmosphere to carbonize the organic fibers and then melted silicon is contained in the molded body. 13. The method for producing a ceramic-based fiber composite material according to claim 11 or 12, wherein impregnation is carried out, and silicon and a carbon component are reacted and sintered to form a matrix made of silicon carbide. 14. The method for producing a ceramic-based fiber composite material according to claim 11, wherein the fiber volume ratio (Vf) of the fiber structure in the composite material is set in the range of 10 to 40% by volume. .