JP2002193679A - Spacer for banking and tool for baking using the spacer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spacer for baking and a tool for baking using the spacer which can maintain the quality of a baked body after their repeated use without lowering the productivity, have great thermal shock resistance and abrasion resistance and can be repeatedly used for a long time. SOLUTION: The spacer 21 for baking set between members 22 to placing multiple baked bodies on them consists of a carbon fiber-reinforced carbon composite material impregnated with silicon(Si) whose porosity is 7% by volume or less and average pore diameter is 0.02 μm or smaller.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a firing spacer and a firing jig using the same. More specifically, a fired body that can maintain the quality of a fired body even after repeated use without reducing productivity, and has extremely high thermal shock resistance and abrasion resistance, and can be used repeatedly for an extremely long time The present invention relates to a spacer for firing and a firing jig using the same.

[0002]

2. Description of the Related Art Magnets and the like used for computer parts are usually about 11 mm in a vacuum or argon atmosphere.
It is manufactured by firing at a high temperature of 00 ° C. This firing is performed by placing a fired body on a firing jig.

[0003] Normally, a firing jig is formed by arranging a plurality of plate members on which a fired body is placed in a hierarchical manner with a predetermined interval provided by a spacer. Conventionally, a reaction with the fired body is performed. For the purpose of prevention, replace all members with molybdenum (Mo)
It was constituted by.

However, in this firing jig, molybdenum (Mo) as a constituent material is not only a high-grade metal but also has a coefficient of thermal expansion smaller than that of iron or stainless steel, but is about 5 × 10 ⁻⁶ /. Because of its relatively high temperature of ℃, it was liable to be deformed by repeated use, and had problems in durability and processing cost.

On the other hand, in recent years, during firing,
A firing jig in which a spacer is made of a carbon fiber reinforced carbon composite material (hereinafter, sometimes referred to as “C / C composite”) having excellent thermal shock resistance and the like is used.

However, in this firing jig, the C / C composite as a constituent material has a high porosity of 10 to 15%, and as shown in FIG.
In addition to 1 μm, it has a pore size distribution with a peak at a large pore size of 10 μm, so that the components released from the fired body are adsorbed in the pores during firing, and the components of the fired body previously fired when firing another product Is released to deteriorate the quality of the fired body.

[0007] Such deterioration of the quality of the fired body can be prevented by firing the firing jig every time each product is fired, that is, by baking the firing jig. Since this is not the case, the productivity of the product is reduced and the production cost is increased.

[0008]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-described problems, and can maintain the quality of a fired body even after repeated use without reducing productivity, and can provide a thermal shock resistance. It is an object of the present invention to provide a firing spacer which has extremely high performance and abrasion resistance and can be used repeatedly for an extremely long time, and a firing jig using the same.

[0009]

Means for Solving the Problems The present inventor has conducted intensive studies to solve the above-mentioned problems, and as a result, the firing spacer has been reduced in porosity and average pore diameter to a specific value or less.
The present inventors have found that the above-mentioned problems can be solved by using a carbon fiber reinforced carbon composite material impregnated with silicon (Si), and have completed the present invention.

That is, according to the present invention, the firing spacer is provided between the plurality of fired body mounting members on which the fired body is mounted, and the constituent material of the fired spacer has a porosity:
There is provided a firing spacer characterized by being a carbon fiber reinforced carbon composite material impregnated with silicon (Si) having a volume fraction of 7% by volume or less and an average pore size of 0.02 μm or less.

In the firing spacer of the present invention,
The carbon fiber reinforced carbon composite material impregnated with silicon (Si) is composed of 55% by mass to 75% by mass of carbon and 1% by mass to 1% by mass.
A yarn composed of 0% by mass of silicon and 10% by mass to 50% by mass of silicon carbide and containing at least a bundle of carbon fibers and a carbon component other than the carbon fibers is three-dimensionally oriented in the layer direction. A composite material comprising a combined yarn assembly that is integrated so as not to be separated from each other, and a matrix made of a Si-SiC-based material filled between adjacent yarns in the yarn assembly; or A Si-SiC / C composite composite material including silicon carbide, carbon fibers, and a carbon component other than carbon fibers, and having a structure including a skeleton portion and a matrix formed around the skeleton portion, wherein at least silicon carbide 50% are beta type,
The skeleton is formed of carbon fibers and carbon components other than carbon fibers, and silicon carbide may be present in a part thereof.The matrix is formed of silicon carbide, and the matrix and the skeleton are integrally formed. The composite material is preferably formed, and more preferably, a uniform layer of silicon carbide or Si—SiC-based material is formed on the surface of the material.

Since the firing spacer of the present invention is excellent in thermal shock resistance and the like, it is preferably applied to a magnet firing jig.

Further, according to the present invention, by disposing such a firing spacer between a plurality of fired body mounting members, the quality of the fired body can be maintained, and the abrasion resistance can be improved. It is possible to provide a firing jig excellent in durability and the like. In this firing jig, molybdenum (Mo) can be used as a constituent material of the fired body mounting member.

[0014]

Embodiments of the present invention will be specifically described below with reference to the drawings.

FIG. 1 is a sectional view showing a firing jig provided with the firing spacer of the present invention, and FIG. 2 is a perspective view schematically showing the firing spacer of the present invention.

As shown in FIG. 1, the firing spacer 21 of the present invention is provided between a plurality of fired body mounting members 22 on which fired bodies are mounted. As shown in FIG. 2, the firing spacer 21 usually includes a fired body mounting member 22.
Has a frame corresponding to the extension of, as shown in FIG.
It is arranged between each of the plate-shaped fired body mounting members 22 arranged in a hierarchy, and forms a certain gap between the fired body mounting members 22.

Next, the constituent materials of the firing spacer of the present invention will be described. The firing spacer of the present invention is made of a C / C composite impregnated with silicon (Si). Thereby, the firing spacer can be composed of a composite material composed of carbon fiber and Si and / or SiC, has high thermal shock resistance under high-temperature firing conditions, and is deformed even after repeated use for an extremely long time. A firing jig which does not cause the baking can be obtained.

The C / C composite impregnated with silicon (Si) has a porosity of 7% by volume or less, preferably 5% by volume or less, and an average pore size of 0.02 μm or less, preferably 0.015 μm or less. Is suppressed. As a result, components released from the fired body are not adsorbed to the pores of the firing spacer, and the quality deterioration of the fired body due to contamination or the like can be prevented without the need for an empty firing step.

Here, in the present specification, “porosity” refers to
It is determined by the following general formula (1) based on the Archimedes method.

Porosity (%) = (water-containing weight−dry weight) / dry weight × 100 · (1)

The “average pore diameter” means an average pore diameter measured by a mercury porosimeter.

The reason why the porosity and the average pore diameter of the C / C composite impregnated with Si are limited to the above-mentioned numerical ranges is that when these values are exceeded, adsorption of components released from the fired body is prevented. This is because the effect becomes insufficient.

As the C / C composite impregnated with silicon (Si) constituting the firing spacer of the present invention, for example, a C / C composite is used as a basic skeleton, and in a state surrounding the basic skeleton, a Si—SiC-based composite is used. Examples thereof include a Si-SiC-based composite material in which a matrix made of a material is formed, and an SiC-based composite material in which a matrix made of a SiC-based material is formed.

The C / C composite is a powdery binder that acts as a matrix of a bundle of carbon fibers, and contains pitches and cokes that become free carbon to the bundle of carbon fibers after firing. A carbon fiber bundle is prepared by further containing a phenol resin powder or the like as necessary, and a flexible film made of a plastic such as a thermoplastic resin is formed around the carbon fiber bundle, thereby forming a flexible intermediate material. The preformed yarn is formed into a sheet or a woven fabric by the method described in Japanese Patent Application Laid-Open No. 2-80639, and the necessary amount is laminated and then formed by hot pressing. It refers to the obtained molded article or a fired article obtained by firing this molded article.

[0024] Specifically, hundreds to tens of thousands of carbon fibers having a diameter of about 10 μm are usually bundled to form a fiber bundle (yarn).
Is formed, and the fiber bundle is covered with a thermoplastic resin to obtain a flexible thread-like intermediate material, which is prepared in Japanese Patent Application Laid-Open No. 2-80639.
No. 4,075,098, which are arranged in a two-dimensional or three-dimensional direction to form a one-way sheet (UD sheet) or various cloths, or to laminate the sheets or cloths. To form a preformed body (fiber preform) having a predetermined shape, and baking a coating of a thermoplastic resin or the like made of an organic substance formed on the outer periphery of the fiber bundle of the preformed body. What has just removed the carbonization of the film may be used. In this specification, the description of Japanese Patent Application Laid-Open No. 2-80639 is cited for reference. In the C / C composite used in the present invention, the carbon component other than the carbon fiber in the yarn is preferably a carbon powder, particularly preferably a graphitized carbon powder.

Further, the Si—SiC-based composite material is 5
5% to 75% by mass of carbon and 1% to 10% by mass
Of silicon and 10% to 50% by mass of silicon carbide, and a yarn containing at least a bundle of carbon fibers and a carbon component other than carbon fibers is three-dimensionally combined while being oriented in the layer direction, A composite material including a yarn aggregate integrated so as not to be separated from each other and a matrix made of a Si-SiC-based material filled between adjacent yarns in the yarn aggregate. This material is an international patent application filed on September 4, 1998 (PCT / J
International Publication WO99 / 192 according to P98 / 04523).
No. 73 can be produced.

The term “Si—SiC-based material” refers to a material containing several different phases from a silicon phase composed of silicon remaining in an unreacted state to almost pure silicon carbide, typically silicon. Phase, and a silicon carbide phase, wherein the silicon carbide phase may include a SiC coexisting phase in which the silicon content changes gradually. Therefore, the Si-SiC-based material is a general term for materials that are contained in the Si-SiC series within a range of 0 mol% to 50 mol% as the concentration of carbon. In this Si-SiC-based composite material, the matrix portion is formed of the Si-SiC-based material.

The Si—SiC-based composite material preferably has a matrix having a gradient composition in which the silicon content increases as the distance from the yarn surface increases. In the Si-SiC-based composite material, preferably, the yarn aggregate made of carbon fibers is composed of a plurality of yarn arrays, and each yarn array is formed by bundling a specific number of carbon fibers. The yarns are formed by two-dimensionally arranging the obtained yarns substantially in parallel, and a yarn aggregate is formed by stacking the respective yarn arrays. Thus, the Si—SiC-based composite material has a multilayer structure in which a plurality of yarn arrays are stacked in a specific direction.

FIG. 3 is a schematic perspective view for explaining the concept of the yarn aggregate, and FIG. 4 (a) is IIa-I in FIG.
FIG. 4B is a cross-sectional view taken along the line Ia, and FIG.
It is a sectional view taken on line b. The skeleton of the Si—SiC-based composite material 7 is constituted by the yarn aggregate 6. The yarn aggregate 6 includes the yarn arrays 1A, 1B, 1C, 1D, 1
E and 1F are vertically stacked. In each yarn array, the yarns 3 are two-dimensionally arranged, and the longitudinal directions of the yarns are substantially parallel. The longitudinal direction of each yarn in each vertically arranged yarn array is orthogonal. That is, the longitudinal direction of each yarn 2A of each of the yarn arrays 1A, 1C, and 1E is parallel to each other, and is orthogonal to the longitudinal direction of each of the yarns 2B of each of the yarn arrays 1B, 1D, and 1F. Each yarn is composed of a fiber bundle 3 composed of carbon fibers and carbon components other than carbon fibers. The yarn assembly 6 having a three-dimensional lattice shape is formed by stacking the yarn arrays. Each yarn is crushed during a pressure forming process as described below, and has a substantially elliptical shape.

In each of the yarn arrays 1A, 1C, and 1E, a matrix 8A is provided between adjacent yarns.
And each matrix 8A extends along and parallel to the surface of the yarn 2A. In each of the yarn arrays 1B, 1D, and 1F, the gap between adjacent yarns is filled with a matrix 8B, and each matrix 8B extends along the surface of the yarn 2B and parallel thereto. In this example, the matrices 8A and 8B are respectively composed of silicon carbide phases 4A and 4B covering the surface of each yarn.
And Si-SiC-based material phases 5A and 5B having a lower carbon content than silicon carbide phases 4A and 4B. Silicon may also be partially contained in the silicon carbide phase. Also,
In this example, silicon carbide phases 4A and 4B are also generated between yarns 2A and 2B that are vertically adjacent to each other. Each matrix 8A and 8B is elongated along the surface of the yarn, preferably in a straight line, and each matrix 8A and 8B is orthogonal to each other. And a matrix 8A in the yarn array 1A, 1C, 1E;
The matrix 8B in the yarn arrays 1B, 1D, and 1F orthogonal to this is continuous at the gap between the yarns 2A and 2B. As a result, matrix 8
A and 8B form a three-dimensional lattice as a whole.

Next, the SiC-based composite material will be described. The SiC-based composite material is a Si-SiC / C composite composite material composed of silicon carbide, carbon fibers, and carbon components other than carbon fibers, and having a structure including a skeleton and a matrix formed around the skeleton. At least 50% of the silicon carbide is β-type, the skeleton is formed of carbon fibers and carbon components other than carbon fibers, and silicon carbide may be present in a part of the skeleton, The matrix refers to a composite material formed of silicon carbide, wherein the matrix and the skeleton are integrally formed.

Therefore, this SiC-based composite material uses a C / C composite in which each carbon fiber is composed of a carbon fiber bundle as a skeleton, and therefore, SiC is partially formed. Also, since each carbon fiber has a structure as a carbon fiber, which is maintained without being broken, the carbon fiber does not become short due to silicon carbide, so that the raw material C / C composite has It has a great feature that the mechanical strength is almost maintained or is increased by silicon carbide. Moreover, the yarn assembly has a composite structure in which a matrix made of a SiC-based material is formed between adjacent yarns. In this regard,
It is different from the above-mentioned Si-SiC-based composite material. This material is disclosed in Japanese Patent Application No. Hei 11-1999 filed on Feb. 9, 1999.
It can be produced by the method disclosed in the specification of Japanese Patent No. 31979.

In the present invention, the C / C composite is impregnated with metallic silicon. At this time, the metallic silicon contains carbon atoms and / or carbon atoms constituting carbon fibers in the composite.
Alternatively, it reacts with the free carbon atoms remaining on the surface of the carbon fiber, and is partially carbonized, so that the outermost surface of the C / C composite or the carbon fiber yarn is partially carbonized. The produced silicon is produced, and thus a matrix made of silicon carbide is formed between the yarns.

The matrix may include several different phases, from a silicon carbide phase in which trace amounts of silicon and carbon are bonded to a pure silicon carbide crystal phase. However, this matrix contains only metallic silicon below the detection limit (0.3% by mass) by X-rays.
That is, although this matrix is typically made of a silicon carbide phase, the silicon carbide phase may include a SiC-based phase in which the content of silicon is inclined. Therefore, the SiC-based material refers to a concentration of carbon of at least 0.01 mol% to 50 mol% in such a SiC series.
It is a generic term for materials contained within the range up to%.
In order to control the carbon concentration to be less than 0.01 mol%, in relation to the amount of free carbon in the C / C composite,
It is not practical because strict measurement of the amount of metallic silicon to be added is required and temperature control in the final step described later is complicated. Therefore, theoretically, the carbon concentration is 0.00
It is possible to control to about 1 mol%.

The Si-based composite material will be further described with reference to the drawings. The skeleton of this SiC-based composite material is basically the same as that shown in FIG. FIG. 5 is a cross-sectional view when the SiC-based composite material according to the present invention is cut along the line IIa-IIa in FIG.
5A is a cross-sectional view taken along line IIb-IIb in FIG. The skeleton of the SiC-based composite material 17 is constituted by the yarn aggregate 16, similarly to the skeleton of the Si—SiC-based composite material 7. The yarn aggregate 16 includes the yarn arrays 11A and 11A.
B, 11C, 11D, 11E, and 11F are vertically stacked. In each yarn array, the yarns 13 are two-dimensionally arranged, and the longitudinal directions of the yarns are substantially parallel. The longitudinal direction of each yarn in each vertically arranged yarn array is orthogonal. That is, the longitudinal direction of each yarn 12A of each yarn array 11A, 11C, 11E is parallel to each other, and each yarn array 11
B, 11D, and 11F are orthogonal to the longitudinal direction of each yarn 12B. Each yarn is composed of a fiber bundle 13 composed of carbon fibers and carbon components other than carbon fibers. The yarn assembly 16 having a three-dimensional lattice shape is formed by stacking the yarn arrays. Each yarn is crushed during a pressing step as described below, and is slightly oval.

Each yarn array 11A, 11C, 11E
In, the gap between adjacent yarns is filled with a matrix 18A, and each matrix 18A extends along and parallel to the surface of the yarn 12A. In each of the yarn arrangements 11B, 11D, 11F, the gap between adjacent yarns is filled with a matrix 18B, and each matrix 18B extends along the surface of the yarn 12B and parallel thereto. As shown in FIGS. 5A and 5B, the matrices 18A and 18B
Represents a silicon carbide phase 1 covering the surface of each yarn.
It consists of four. A part of the silicon carbide phase is
Or may protrude into the carbon fiber layer inside the composite member. Inside such small projections, pores (voids: 15) having a median diameter of about 100 μm are formed. In addition, since the small protrusions 19 are formed along the traces of the matrix composed of carbon components other than the carbon fibers of the raw material C / C composite, the gap between the yarns and / or the arrangement of the yarns is small. By appropriately selecting the distance from the yarn array, it is possible to adjust the density of the small projections 19 per unit area. Silicon carbide phase 14 may be formed between adjacent yarns 12A and 12B.

Each of the matrices 18A and 18B is elongated, preferably linear, respectively, along the surface of the yarn, and each of the matrices 18A and 18B is orthogonal to one another. Then, the yarn arrays 11A, 11
The matrix 18A in C and 11E and the matrix 18B in the yarn arrays 11B, 11D and 11F orthogonal thereto are continuous at the gap between the yarns 12A and 12B, respectively. As a result, matrix 1
8A and 18B form a three-dimensional lattice as a whole.

In the firing spacer of the present invention, such a C / C composite composite material impregnated with Si is:
Further, it is preferable to form a uniform layer made of silicon carbide or Si—SiC-based material on the surface of the material.

The presence of the matrix made of silicon carbide or Si—SiC-based material can reduce the difference in thermal expansion between the material surface and the other parts at the time of high temperature use, and can provide uniform silicon carbide or Si—SiC surface. Since the abrasion resistance can be further improved by the presence of the layer made of the system material, damage due to rubbing or the like with the fired body mounting member can be highly prevented, and the durability can be further improved.

The uniform silicon carbide or Si—SiC-based material layer is formed by manufacturing the above-described C / C composite composite material in which a matrix made of silicon carbide or a Si—SiC-based material is present. ℃,
It can be formed by firing for 1 to 3 hours.

It should be noted that “uniform” means a case where a layer is formed only on a part of the surface, and does not limit the thickness of the layer. However, in consideration of the difference in thermal expansion between the material surface and other portions and the wear resistance, 30
A thickness of ~ 300 [mu] m is preferred.

According to the present invention, as shown in FIG. 1, by providing the firing spacer 21 described above between the plurality of fired body mounting members 22, the quality of the fired body is improved. A firing jig 20 that can be maintained and has excellent heat resistance, abrasion resistance, durability, and the like can be provided. At this time, the constituent material of the fired body mounting member 22 is molybdenum (M
o).

[0042]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

1. Evaluation Method The properties of the jig were evaluated for the firing spacers obtained in Examples and Comparative Examples by the following evaluation methods.

(Abrasion Resistance) The object to be fired is placed on a firing jig provided with firing spacers, and fired at about 1100 ° C. for 2 weeks in an argon gas atmosphere. With respect to the firing spacers taken out and taken out between the respective fired body mounting members, the presence or absence of scratches was visually confirmed.

(Average pore size) The average pore size was measured by a mercury porosimeter.

(Porosity) The porosity was measured by the following general formula (1) based on the Archimedes method.

[Formula 2] Porosity (%) = (Wet weight−Dry weight) / Dry weight × 100 · (1)

(Adsorption Amount of Fired Body Component) After the weight of the fired spacer was measured, the fired body was placed on a fired jig provided with the fired spacer, and the fired body was placed under an argon gas atmosphere. After sintering at 2 ° C. for 2 weeks, the weight of the sintering spacer was measured again, and the increased weight after sintering was taken as the amount of adsorption of the sintered body component.

[0048] 2. EXAMPLES, COMPARATIVE EXAMPLES Example 1 By impregnating a carbon fiber unidirectionally in one direction with a phenol resin, about 10,000 carbon fibers having a diameter of 10 μm are bundled to obtain a fiber bundle (yarn). They were arranged as shown in FIG. 3 to obtain a prepreg sheet. Next, this prepreg sheet is laminated in 20 steps,
The treatment was performed at 0 ° C. and 30 kg / cm ² to cure the phenol resin. Next, the mixture was fired at a temperature of 2000 ° C. in a nitrogen atmosphere to obtain a C / C composite having a thickness of 10 mm. The density of the obtained C / C composite was 1.5 g / cm ³ ,
The porosity was 15% by volume.

Next, the obtained C / C composite is
The carbon crucible was set up in a carbon crucible filled with Si powder having a purity of 99.8% and an average particle diameter of 1 mm, and was moved into a firing furnace. The firing was performed at a firing furnace temperature of 1300 ° C. and a firing furnace pressure of 1 hPa at a flow rate of 2 inert gas argon gas.
After processing for 4 hours while flowing at 0 NL / min,
While maintaining the pressure in the sintering furnace,
The temperature was raised to 00 ° C. to obtain an Si—SiC composite material in which C / C composite was impregnated with Si. Finally, a substantially rectangular parallelepiped firing spacer was manufactured by grinding.

Example 2 In Example 1, the sintering was performed at a temperature in the sintering furnace of 1300 ° C.
After the treatment was performed for 4 hours while maintaining the pressure in the firing furnace at 4 h while the inert gas argon gas was flown at a flow rate of 20 NL / min at a pressure of 1 hPa in the firing furnace, the temperature in the furnace was raised to 1800 ° C. A firing spacer was manufactured in the same manner as in Example 1 except that the firing was performed.

Example 3 In Example 1, the sintering was performed at a temperature of 1300 ° C. in a sintering furnace.
After treating for 4 hours while maintaining an internal pressure of the firing furnace at 4 h while flowing an inert gas of argon gas at a flow rate of 20 NL / min, the furnace temperature is increased to 2000 ° C. while maintaining the pressure in the firing furnace. A firing spacer was manufactured in the same manner as in Example 1 except that the firing was performed.

Example 4 A sintering spacer was manufactured in the same manner as in Example 1, and baked at 2200 ° C. for 1 hour to form a 100 μm thick film on the surface.
Was formed.

Comparative Example 1 After a C / C composite was obtained by the method described in Example 1, a firing spacer having the same shape as that of Example 1 was manufactured by grinding.

[0054] 3. Evaluation Results In the firing spacers of Examples 1 to 3 made of a C / C composite composite material impregnated with Si (there is no formation of a layer made of silicon carbide or a Si—SiC-based material on the surface),
The porosity is 5% by volume, the average pore size is 0.013 μm,
The adsorption amount of the fired body component was extremely small at 0.5 g. Further, the coefficient of thermal expansion was as small as 1.4 × 10 ⁻⁶ / ° C., and the surface of the jig after removing the product was in a good state without any scratches or deformation.

Further, in the firing spacer of Example 4 made of a material in which a layer made of silicon carbide was formed on the surface of a C / C composite composite material impregnated with Si, the porosity was 3% by volume and the average pore size was 0. 0.013 μm, and the adsorption amount of the fired body component was extremely small at 0.3 g. Further, the coefficient of thermal expansion was as small as 1.4 × 10 ⁻⁶ / ° C., and the surface of the jig after removing the product was in a good state without any scratches or deformation. In this firing spacer, since a layer made of silicon carbide is formed on the surface of the material, it is presumed that the abrasion resistance is large and the durability is further improved.

On the other hand, in the dimensional correction jig of Comparative Example 1 made of a C / C composite, the thermal expansion coefficient was 1.0 × 10
Although it is as small as ^-6 / ° C., the porosity is 10% by volume, the average pore size is 0.03 μm, and the adsorption amount of the fired body component is 3.0.
g. In addition, after the product was taken out, delamination was observed on a part of the firing spacers taken out between the respective fired body mounting members, possibly due to shear resistance generated between the fired body mounting members. The evaluation results are shown in Table 1 and FIGS.

[0057]

[Table 1]

[0058]

As described above, according to the firing spacer of the present invention, the quality of the fired body can be maintained by repeated use without lowering the productivity, and the thermal shock resistance and the wear resistance can be maintained. It is possible to provide a firing spacer which has extremely high wearability and can be used repeatedly for an extremely long time, and a firing jig using the same.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically showing a firing jig in which a firing spacer according to one embodiment of the present invention is disposed between fired body mounting members.

FIG. 2 is a perspective view schematically showing one embodiment of a firing spacer of the present invention.

FIG. 3 is a perspective view schematically showing a structure of a yarn aggregate which is a basic structure of a composite material used for a firing spacer of the present invention.

FIG. 4A is a cross-sectional view of the Si—SiC-based composite material cut along a line IIa-IIa in FIG. 3;
(B) is a cross-sectional view of the same material cut along line IIb-IIb in FIG. 3.

FIG. 5 (a) shows the SiC-based composite material as IIa in FIG. 3;
FIG. 2B is a cross-sectional view taken along line IIa, and FIG.
FIG. 4 is a cross-sectional view when the same material is cut along a line IIb-IIb in FIG. 3.

FIG. 6 is a graph showing the pore distribution of the firing spacer of the present invention.

FIG. 7 is a graph showing a pore distribution of a conventional firing spacer.

[Explanation of symbols]

1A, 1B, 1C, 1D, 1E and 1F: yarn array, 2A: yarn, 2B: yarn, 3: fiber bundle (yarn), 4A: silicon carbide phase, 4B: silicon carbide phase, 4C: silicon carbide phase, 5A ... Si-SiC material phase, 5B ... Si-
SiC-based material phase, 5C: Si-SiC-based material phase, 6: Yarn aggregate, 7: Fiber composite material, 8A: Matrix,
8B ... matrix, 11A, 11B, 11C, 11
D, 11E and 11F: yarn array, 12A: yarn, 12B: yarn, 13: fiber bundle (yarn), 14:
Silicon carbide phase, 15 ... voids, 16 ... yarn aggregate, 17 ...
Fiber composite material, 18A matrix, 18B matrix, 20 firing jig, 21 firing spacer,
22 ... Fired body mounting member.

Claims (6)

[Claims] 1. A firing spacer disposed between a plurality of firing body mounting members for mounting a firing body, wherein the constituent material of the firing spacer has a porosity of 7% by volume or less, and Average pore size: 0.02 μm or less, silicon (S
A firing spacer, which is a carbon fiber reinforced carbon composite material impregnated with i). 2. The carbon fiber reinforced carbon composite material impregnated with silicon (Si) comprises 55% by mass to 75% by mass of carbon, 1% by mass to 10% by mass of silicon, and 10% by mass to 5% by mass.
A yarn composed of 0% by mass of silicon carbide and containing at least a bundle of carbon fibers and a carbon component other than carbon fibers is three-dimensionally combined while being oriented in the layer direction and integrated so as not to be separated from each other. A composite material comprising: a yarn aggregate that is filled; and a matrix made of a Si—SiC-based material filled between the yarns adjacent to each other in the yarn aggregate; or a material other than silicon carbide, carbon fiber, and carbon fiber. Si-SiC composed of a carbon component and having a structure composed of a skeleton and a matrix formed around the skeleton.
/ C composite composite material, wherein at least 50% of the silicon carbide is β-type, the skeleton is formed of the carbon fiber and a carbon component other than the carbon fiber, and silicon carbide is partially present. 2. The firing spacer according to claim 1, wherein the matrix is formed of the silicon carbide, and the matrix and the skeleton are a composite material integrally formed. 3. 3. The carbon fiber reinforced carbon composite material impregnated with Si further forms a uniform layer made of silicon carbide or Si—SiC material on the surface of the material.
3. The firing spacer according to item 1. 4. The firing spacer according to claim 1, which is applied to a magnet firing jig. 5. A firing jig, wherein the firing spacer according to claim 1 is disposed between the plurality of fired body mounting members. 6. The firing jig according to claim 5, wherein a constituent material of the fired body mounting member is molybdenum (Mo).