JP5093165B2 - Structure manufacturing method and structure - Google Patents

Description

  The present invention relates to a structure including a hollow region connected to the outside through an opening and formed of a ceramic matrix composite material and a method for manufacturing the structure.

In recent years, ceramic-based composite materials having excellent heat resistance in place of metals may be used as materials for forming structures.
Such a ceramic matrix composite material is a material in which a matrix made of ceramic is attached to a fabric made of fibers made of ceramic, and has heat resistance superior to that of metal.

  When manufacturing a structure such as a turbine blade or a combustion chamber having a hollow region inside using such a ceramic matrix composite material, for example, a fiber made of ceramic is wound around a mandrel formed in the shape of the hollow region. To form a fabric in the shape of a structure, and a matrix is deposited on the fabric.

US Pat. No. 7,093,359

By the way, as a method of winding a fiber around a mandrel formed in the shape of a hollow region of a structure, a so-called braiding method and a filament winding method are known.
The braiding method is a method in which a central yarn extending in the extending direction of the mandrel and a plurality of braids wound spirally around the mandrel are knitted, and a plurality of fibers are simultaneously wound around the mandrel. is there.
On the other hand, the filament winding method is a method of winding a single fiber around a mandrel.

However, an actual structure generally has a complicated shape. For this reason, the mandrel molded into the shape of the hollow region of the structure often has a complicated shape.
When a fiber is wound around a mandrel having such a complicated shape, a part of the fiber moves along the shape of the mandrel, and the fiber is biased in the woven fabric.
The strength of the structure formed of the ceramic matrix composite material depends on the fiber density and fiber direction. For this reason, when there is a fiber bias, the strength of the structure becomes non-uniform, and the strength may change depending on the location.

  The present invention has been made in view of the above-described problems, and an object thereof is to improve the quality of a structure by making the strength of the structure formed of a ceramic matrix composite material uniform.

  The present invention adopts the following configuration as means for solving the above-described problems.

  1st invention is a manufacturing method of the structure provided with the hollow area | region connected outside via an opening part, and is formed with a ceramic matrix composite material, Comprising: The cross-sectional shape in a length direction is centering on a central axis Forming a woven fabric in which a cross-sectional shape in the lengthwise direction is formed into a hollow concentric shape centering on the central axis by winding a fiber made of ceramic around a concentric circular mandrel, and forming the woven fabric A configuration is adopted in which the woven fabric formed in the step is deformed into the shape of the structure, and the matrix is formed by impregnating the woven fabric with ceramic to form a matrix.

  According to a second invention, in the first invention, the circumference in each region in the length direction of the mandrel is matched with the circumference in each region in the length direction of the hollow region of the structure. The configuration is adopted.

  According to a third invention, in the first or second invention, a configuration is adopted in which the mandrel is removable or disappearable in a state where the fiber is wound.

  According to a fourth invention, in any one of the first to third inventions, in the matrix formation step, an inner mold molded into the shape of the hollow region of the structure and an outer shape molded into the outer shape of the structure A configuration is adopted in which the fabric is deformed into the shape of the structure by being sandwiched by a mold.

  A fifth invention adopts a configuration in which, in the fourth invention, the inner mold is removable or disappearable in the hollow region of the structure.

  6th invention employ | adopts the structure that the said textile fabric is wound around the said mandrel by the braiding method in any one of said 1st-5th invention.

  7th invention employ | adopts the structure which arrange | positions the small fabric smaller than the said fabric in the said fabric in any one of the said 1st-6th invention, and performs the said matrix formation process.

  An eighth invention is a structure having a hollow region connected to the outside through an opening and formed of a ceramic matrix composite material, wherein the cross-sectional shape in the length direction is a hollow centered on the central axis A configuration is adopted in which a woven fabric having a concentric shape is formed by impregnating a ceramic into a deformed fabric obtained by deforming the shape of the structure.

According to the present invention, a fabric whose cross-sectional shape in the length direction is a concentric circle centered on the central axis is deformed into a structure, and the deformed fabric is impregnated with ceramic to form a structure. .
A fabric in which the cross-sectional shape in the length direction has a hollow concentric shape centering on the central axis has the same curvature in a single cross-section, and therefore, the fibers can be arranged uniformly around the central axis. In other words, in a fabric in which the cross-sectional shape in the length direction is a hollow concentric circle centered on the central axis, the fiber bias is suppressed in the circumferential direction centered on the central axis. And even if it is a case where such a textile fabric is changed into the shape of a structure, the density of the fiber in a textile fabric becomes uniform around the central axis.
For this reason, like the present invention, the fabric is deformed into the shape of a structure, and the deformed fabric is impregnated with ceramic, thereby forming a structure in which fibers are uniformly arranged in the circumferential direction.
Therefore, according to the present invention, it is possible to improve the quality of the structure by making the strength of the structure formed of the ceramic matrix composite material uniform.

It is a perspective view which shows schematic structure of the stationary blade in 1st Embodiment of this invention. It is a perspective view of the mandrel used when forming the stationary blade in 1st Embodiment of this invention. It is a perspective view which shows a mode that the textile fabric was formed around the mandrel used when forming the stationary blade in 1st Embodiment of this invention. It is a figure which shows a mode that the textile fabric used when forming the stationary blade in 1st Embodiment of this invention was deform | transformed. It is a figure which shows a mode that the textile fabric used when forming the stationary blade in 1st Embodiment of this invention was pinched | interposed by the inner type | mold and the outer type | mold. It is a perspective view which shows schematic structure of the stationary blade in 2nd Embodiment of this invention. It is a perspective view of the mandrel used when forming the stationary blade in 2nd Embodiment of this invention. It is a perspective view which shows a mode that the textile fabric was formed around the mandrel used when forming the stationary blade in 2nd Embodiment of this invention. It is a figure which shows the modification of this invention, and is a figure which shows the process of manufacturing the stationary blade by which the hollow area was divided into two. It is a figure which shows the modification of this invention, and is a figure which shows the process of manufacturing the stationary blade in which the hollow area was divided into three. It is a figure which shows the modification of this invention, and is a figure which shows the process of manufacturing the stationary blade by which the hollow area | region was divided into two in the up-down direction.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of a structure manufacturing method and a structure according to the invention will be described with reference to the drawings. In the following description, a case where the structure is a turbine stationary blade will be described.

(First embodiment)
FIG. 1 is a perspective view showing a schematic configuration of a stationary blade 1 of a turbine according to the present embodiment. As shown in this figure, the stationary blade 1 includes a hollow region 1a connected to the outside through openings on both sides. When the stationary blade 1 is actually incorporated into the turbine, the opening is closed by the band portions arranged on both sides of the stationary blade 1, and the cooling gas is supplied to the hollow region 1a, whereby the stationary blade 1 Cooling is achieved.

Further, the stationary blade 1 of the present embodiment is formed of a ceramic matrix composite material.
A ceramic matrix composite material is a material in which a matrix made of ceramic (for example, silicon carbide) is adhered to a fabric formed by fibers made of ceramic (for example, silicon carbide), and exhibits excellent heat resistance even with metal. .

In the stationary blade 1 according to the present embodiment, a ceramic is impregnated into a deformed fabric obtained by transforming a fabric having a cross-sectional shape in the length direction into a hollow concentric shape centered on the central axis L2 into the shape of the stationary blade 1. Is formed. In addition, the length direction said here is a direction where the central axis L2 extends.
According to the stator blade 1 of this embodiment, the density of fibers around the axis L that passes through the openings on both sides through the hollow region 1a is made uniform and the strength is made uniform, so that the quality is improved. It will be.

Then, the manufacturing method of such a stationary blade 1 is demonstrated.
First, as shown in FIG. 2, a mandrel 100 is prepared in which the cross-sectional shape in the length direction, which is the extending direction of the central axis L2, is a concentric shape centering on the central axis L2. When such a mandrel 100 is cut by a plane orthogonal to the central axis L2 in any region in the length direction, the cross-sectional shape thereof becomes a perfect circle.
In this embodiment, the mandrel 100 has a circular shape with the same radius in all the regions in the length direction, and the circumferential length in each region in the length direction of the mandrel 100 is each in the length direction of the hollow region 1a. It is consistent with the perimeter in the area.

Next, as shown in FIG. 3, by wrapping a fiber made of ceramic around the mandrel 100, a woven fabric 2 is formed in which the cross-sectional shape in the length direction is a hollow concentric circle centered on the central axis L2 ( Fabric formation process).
In the present embodiment, the fiber is wound around the mandrel 100 by a braiding method. By the braiding method, a central yarn extending in the extending direction of the mandrel 100 and a plurality of braids wound spirally around the mandrel 100 are knitted, and a plurality of fibers are wound around the mandrel 100 simultaneously.

  Next, the mandrel 100 is extracted from the fabric 2. In addition, in this embodiment, since the mandrel 100 has a circular shape with the same radius in all the regions in the length direction, the mandrel 100 can be easily extracted from the fabric 2 by restraining the fabric 2 and moving it in the central axis L direction. Can do.

In the ceramic matrix composite material, an interface layer is formed on the surface of the fiber as is well known. And when forming a carbon interface layer as the said interface layer, the interface layer is formed by heat-treating the textile fabric 2 which extracted the mandrel 100 in the vacuum furnace supplied with methane gas, and thermally decomposing.
However, when a boron nitride interface layer is formed as the interface layer, the interface layer is formed before the fibers are wound around the mandrel 100. Specifically, the interface layer is formed by thermal decomposition through fibers in a furnace to which BCl ₃ + NH ₃ gas is supplied.

Next, as shown in FIG. 4, the inner mold 200 molded in the shape of the hollow region 1 a of the stationary blade 1 is inserted into the fabric 2 from which the mandrel 100 is extracted, and the fabric 2 is pressed against the inner mold 200. As a result, the fabric 2 is deformed into the shape of the stationary blade 1.
Next, as shown in FIG. 5, the fabric 2 is changed to the shape of the stationary blade 1 by sandwiching the fabric 2 between the inner mold 200 and the outer mold 300 molded into the outer shape of the stationary blade 1. keep. The outer mold 300 includes a plurality of through holes that reach the fabric 2 so that the raw material can easily reach the fabric 2 in the subsequent impregnation process.

Then, in a state where the fabric 2 is changed to the shape of the stationary blade 1 in this manner, the fabric 2 is impregnated with ceramic to form a matrix (matrix forming step).
As methods for impregnating the fabric 2 with ceramic, for example, a vapor phase impregnation method, a liquid phase impregnation method, and a solid phase impregnation method are known. In the present embodiment, an impregnation treatment combining these methods alone or in combination is performed, and a dense matrix is formed by repeating these impregnation treatments.

In the impregnation process, the gap between the fabric 2 and the inner mold 200 and the gap between the fabric 2 and the outer mold 300 are also impregnated with ceramic. Therefore, when the impregnation of the ceramic into the fabric 2 proceeds, the inner mold 200 and the outer mold It becomes difficult to remove the fabric 2 from 300. On the other hand, the shape of the fabric 2 is fixed at an initial stage of the impregnation process (a stage in which a small amount of ceramic is impregnated in the fabric 2).
For this reason, it is preferable to remove the fabric 2 from the inner mold 200 and the outer mold 300 in the initial stage of the impregnation process, and then perform the impregnation process only for the fabric 2.

The stator blade 1 shown in FIG. 1 is manufactured by the process as described above.
According to the manufacturing method of the stationary blade 1 of this embodiment, the fabric 2 having a cross-sectional shape in the length direction that is concentric with the central axis L2 as the center is deformed into the shape of the stationary blade 1, and this deformation is performed. The woven fabric 2 (deformed fabric) is impregnated with ceramic to form the stationary blade 1.
Since the woven fabric 2 in which the cross-sectional shape in the length direction is a hollow concentric circle centered on the central axis L2 has the same curvature in a single cross section, it is uniform around the central axis L2 when the fibers are wound around the mandrel 100 It becomes possible to arrange | position a fiber. That is, in the fabric 2 in which the cross-sectional shape in the length direction is a hollow concentric shape centering on the central axis L2, the fiber bias is suppressed in the circumferential direction centering on the central axis L2. Even when the fabric 2 is deformed into the shape of the stationary blade 1, the fiber density in the fabric 2 is uniform around the central axis L2.
For this reason, like the manufacturing method of the stationary blade 1 of the present embodiment, the fabric 2 is deformed into the shape of the stationary blade 1, and the deformed fabric 2 is impregnated with ceramic, so that the fibers are uniform in the circumferential direction. It becomes the stationary blade 1 arrange | positioned at.
Therefore, according to the stationary blade 1 of the present embodiment, it is possible to improve the quality of the stationary blade 1 by making the strength of the stationary blade 1 formed of the ceramic matrix composite material uniform.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. In the description of the second embodiment, the description of the same parts as in the first embodiment will be omitted or simplified.

FIG. 6 is a perspective view showing a schematic configuration of the stationary blade 3 of the present embodiment. As shown in this figure, the stationary blade 3 of the present embodiment has a cross-sectional shape of the central portion A larger than that of the front side (hub side) in the direction of the axis L1, and a cross-section of the back side B (tip side). The shape is smaller than the cross-sectional shape on the near side (hub side).
The stationary blade 3 formed in this embodiment is also formed of a ceramic matrix composite material, and has a hollow region 3a inside.

  And the stationary blade 3 of this embodiment is also the thing which the density of the fiber around the axis | shaft L was equalized and the intensity | strength was equalized, and the quality was improved similarly to the stationary blade 1 of the said 1st Embodiment. It has become.

When manufacturing the stationary blade 3 of the present embodiment having such a configuration, as shown in FIG. 7, the cross-sectional shape of the central portion A1 in the direction of the central axis L2 is a perfect circle larger than the cross-sectional shape on the near side. A mandrel 600 having a perfect circle whose cross-sectional shape on the back side B1 is smaller than the cross-sectional shape on the near side is prepared.
Note that the circumferential length of the mandrel 600 at the central portion A <b> 1 matches the circumferential length of the hollow region 3 a at the central portion A of the stationary blade 3. Further, the circumference of the mandrel 600 on the back side B <b> 1 matches the circumference of the hollow region 3 a on the back side B of the stationary blade 3.

  Next, as shown in FIG. 8, the fabric 4 is formed by winding fibers made of ceramic around the mandrel 600. Although the cross-sectional shape of the woven fabric 4 changes in the direction of the central axis L2, the cross-sectional shape of all the regions in the central axis L2 direction is hollow with the central axis L2 as the center in the same manner as the woven fabric 2 of the first embodiment. Concentric circular shape.

Next, the mandrel 600 is extracted from the fabric 4. In addition, since center part A1 of the mandrel 600 is larger than the near side and the back side, the mandrel 600 cannot be extracted from the fabric 4 as it is.
Therefore, for example, it is preferable that the mandrel 600 is constituted by a core part and a peripheral part arranged around the core part, and can be disassembled by extracting the core part. As a result, the mandrel 600 can be easily extracted. That is, it is preferable that the mandrel 600 is configured to be disassembled in a state where the fabric 4 is wound.
In addition, the mandrel 600 may be dissolved and removed by a medicine or the like. Alternatively, the mandrel 600 can be removed by burning out.
As described above, the mandrel 600 can be removed or disappeared in a state in which the fabric 4 is wound using any method.

Next, an inner mold molded in the shape of the hollow region 3a of the stationary blade 3 is inserted into the fabric 4 from which the mandrel 600 has been extracted, and the fabric 4 is pressed against the inner mold, thereby causing the fabric 4 to move to the stationary blade 3. Transform to shape.
Here, since the size of the cross-sectional shape of the hollow region 3 a of the stationary blade 3 changes in the length direction of the stationary blade 3, the size of the cross-sectional shape of the inner mold similarly changes in the length direction. For this reason, the inner mold cannot be inserted into the fabric 4 as it is. For this reason, the inner mold is configured to be disassembled, and can be assembled in the fabric 4 while being put into the fabric 4 in a disassembled state.
It is also possible to remove the inner mold from the hollow region 3a by disposing it so that it can be burned out or dissolving it with chemicals, etc., and burning out or dissolving the internal mold.
As described above, the inner mold can be lost in the hollow region 3 a of the stationary blade 3 using any of the methods.

  Next, while maintaining the state in which the fabric 4 is changed to the shape of the stationary blade 3 by sandwiching the fabric 4 between the inner mold and the outer mold molded into the outer shape of the stationary blade 3, the first embodiment and Similarly, the fabric 4 is impregnated with ceramic to form a matrix.

Also in the manufacturing method of the stationary blade 3 of the present embodiment as described above, as in the first embodiment, the fabric 4 having a cross-sectional shape in the length direction that is a concentric circle centered on the central axis L2 is used. 3, and the deformed fabric 4 (deformed fabric) is impregnated with ceramic to form the stationary blade 3.
Since the woven fabric 2 in which the cross-sectional shape in the length direction is a hollow concentric circle centered on the central axis L2 has the same curvature in a single cross section, it is uniform around the central axis L2 when the fibers are wound around the mandrel 600 It becomes possible to arrange | position a fiber. That is, in the fabric 4 in which the cross-sectional shape in the length direction is a hollow concentric shape centered on the central axis L2, the fiber bias is suppressed in the circumferential direction centered on the central axis L2. Even when the fabric 4 is deformed into the shape of the stationary blade 1, the fiber density in the fabric 4 is uniform around the central axis L2.
Therefore, as in the method of manufacturing the stationary blade 3 of the present embodiment, the fabric 4 is deformed into the shape of the stationary blade 3, and the deformed fabric 4 is impregnated with ceramic, so that the fibers are uniform in the circumferential direction. It becomes the stationary blade 3 arrange | positioned to.
Therefore, according to the stationary blade 3 of the present embodiment, it is possible to make the strength of the stationary blade 3 formed of the ceramic matrix composite material uniform and improve the quality of the stationary blade 3.

  As mentioned above, although preferred embodiment of this invention was described referring drawings, this invention is not limited to the said embodiment. Various shapes, combinations, and the like of the constituent members shown in the above-described embodiments are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

For example, in the above embodiment, the configuration in which the structure of the present invention is a stationary blade of a turbine has been described.
However, this invention is not limited to this, The structure in this invention should just be a structure provided with a hollow area | region and formed with a ceramic matrix composite material. For example, examples of the structure of the present invention include a turbine blade and a combustor in addition to a turbine stationary blade.

Moreover, in the said embodiment, the structure which winds a fiber around a mandrel by the braiding method was demonstrated.
However, the present invention is not limited to this, and fibers may be wound around the mandrel by, for example, a filament winding method. This filament winding method is a method of winding a single fiber around a mandrel. Even when the fiber is wound around the mandrel using such a filament winding method, by winding the fiber around the mandrel whose cross-sectional shape in the length direction is a hollow concentric circle centering on the central axis, It is possible to form a woven fabric whose cross-sectional shape in the length direction is a hollow concentric circle centered on the central axis. It is possible to manufacture a stationary blade in which fibers are arranged at a uniform density around an axis.

Moreover, in the said embodiment, the structure which deform | transforms a single fabric and manufactures a stationary blade was demonstrated.
However, the present invention is not limited to this.
For example, as shown in FIG. 9, a woven fabric 2a (small woven fabric) smaller than the woven fabric 2 shown in the first embodiment is formed in the same manner as the woven fabric 2, and the woven fabric 2a is formed inside the woven fabric 2. By arranging and deforming, a stationary blade in which the hollow region 1a is divided into two can be manufactured.
Further, as shown in FIG. 10, woven fabrics 2b and 2c (small woven fabrics) smaller than the woven fabric 2 shown in the first embodiment are formed by the same method as the woven fabric 2, and the woven fabrics 2b and 2c are formed by the woven fabric. By arranging and deforming the inside of 2, a stationary blade in which the hollow region 1 a is divided into three can be manufactured.
Further, as shown in FIG. 11, woven fabrics 2d and 2e (small woven fabrics) smaller than the woven fabric 2 shown in the first embodiment are formed by the same method as the woven fabric 2, and the woven fabrics 2d and 2e are formed as a woven fabric. It is possible to manufacture a stationary blade in which the hollow region 1a is divided into two in the vertical direction by arranging and deforming in the vertical direction inside 2.

  1, 3 ...... Stator blade (structure), 1 a, 3 a ...... hollow region, 2, 2 a to 2 e, 4 ...... textile, 100, 600 …… mandrel, 200 …… inner mold, 300 …… outer mold

Claims (8)

A manufacturing method of a structure including a hollow region connected to the outside through an opening and formed of a ceramic matrix composite material,
By wrapping ceramic fibers around a mandrel whose cross-sectional shape in the length direction is concentric with the central axis as the center, the cross-sectional shape in the length direction is made into a hollow concentric shape with the central axis as the center. A fabric forming process for forming a fabric;
And a matrix forming step of forming a matrix by impregnating the fabric with a ceramic in a state in which the fabric formed in the fabric forming step is deformed into the shape of the structure. Method   2. The structure according to claim 1, wherein a circumferential length in each region in the length direction of the mandrel coincides with a circumferential length in each region in the length direction of the hollow region of the structure. Production method.   3. The method of manufacturing a structure according to claim 1, wherein the mandrel is removable or disappearable in a state where the fiber is wound.   In the matrix forming step, the woven fabric is deformed into the shape of the structure by being sandwiched between an inner mold molded into the shape of the hollow region of the structure and an outer mold molded into the outer shape of the structure. The manufacturing method of the structure in any one of Claims 1-3 characterized by these.   The method for manufacturing a structure according to claim 4, wherein the inner mold is removable or disappearable in the hollow region of the structure.   The method for producing a structure according to any one of claims 1 to 5, wherein the fabric is wound around the mandrel by a braiding method.   The method for manufacturing a structure according to any one of claims 1 to 6, wherein the matrix forming step is performed by arranging a small woven fabric smaller than the woven fabric inside the woven fabric. A structure having a hollow region connected to the outside through an opening and formed of a ceramic matrix composite material,
A structure in which a cross-sectional shape in a length direction is a hollow concentric circle centered on a central axis, and is formed by impregnating a ceramic into a deformed fabric obtained by deforming the shape of the structure. .

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