JP7056394B2 - Fiber reinforced composites and woven base materials - Google Patents

Description

The present invention relates to a fiber reinforced composite material and a woven fabric base material.

Fiber reinforced composites are used as lightweight and high-strength materials. The fiber-reinforced composite material is preferable as a structural component because the woven fabric base material made of reinforced fiber is composited with the resin to improve the mechanical properties (mechanical properties) as compared with the resin itself.

The woven base material of such a fiber-reinforced composite material is made by weaving a warp and weft, which is a first thread, and a weft, which is a second thread, and is shaped along a molding die for the fiber-reinforced composite material. Manufactured. However, in the manufacturing of the woven fabric base material, when the woven fabric base material is shaped, the warp and weft are routed inside and outside due to the bending at the portion arranged in the bent portion or the curved portion of the molding die in the woven fabric base material. It meanders due to the difference in difference. If the woven fabric base material is impregnated with the resin while the warp and weft are meandering, the strength of the meandering portion of the obtained fiber-reinforced composite material is lowered.

Therefore, as a technique for forming a woven fabric base material by eliminating the meandering of threads in the woven fabric base material, for example, Patent Document 1 can be mentioned. In the woven fabric base material disclosed in Patent Document 1, the woven structure of the first portion, which is a curved portion, is formed by satin weave, and the woven structure of the second portion, which is a non-curved general portion, is formed by plain weave. .. The first portion is formed of a woven structure having a wider pitch between the crossed portions of the warp and weft than the second portion. Therefore, the restraining points of both yarns due to the crossing of the warp and weft are smaller in the first portion, and the first portion is easier to shape than the second portion. Therefore, when the first portion is shaped, even if the meandering of the yarn occurs in the first portion, the warp and weft of the first portion are easily displaced to eliminate the meandering generated in the woven fabric base material.

Japanese Unexamined Patent Publication No. 2013-245417

In the woven fabric base material and the fiber-reinforced composite material of Patent Document 1, the first part is a satin weave, the second part is a plain weave, and the weaving composition is different between the first part and the second part. For this reason, the extension of the yarn spindles of the weft and warp differs between the first portion and the second portion, and in the fiber-reinforced composite material and the woven fabric base material, the strength difference between the first portion and the second portion becomes large. There is.

An object of the present invention is to provide a fiber-reinforced composite material and a woven fabric base material capable of reducing the strength difference between a general portion and a bent portion.

The fiber-reinforced composite material for solving the above problems includes a plurality of first threads arranged in parallel with each other and a plurality of second threads arranged in parallel with each other and in a direction intersecting the first threads. A fiber-reinforced composite material in which a matrix resin is composited with a woven base material provided with a thread, wherein the woven base material is bent or curved with respect to a flat plate-shaped general portion and the general portion, and is formed by the general portion. The first yarn and the second yarn have a bending portion having a surface intersecting with the surface, and the core yarn made of a reinforcing fiber and a covering yarn spirally wound around the core yarn. And, in the first yarn and the second yarn, the magnitude of the inclination of the covering yarn with respect to the yarn main shaft at the portion constituting the general portion is set as the inclination angle θA, and the bent portion is formed. Assuming that the magnitude of the inclination of the covering yarn with respect to the yarn main axis at the portion to be inclined is the inclination angle θB, the gist is that the inclination angle θB > the inclination angle θA is established.

Regarding the inclination angle of the covering yarn with respect to the core yarn, the fact that the inclination angle θB ≧ inclination angle θA is established means that the covering yarn at the bending portion is formed even before the woven fabric base material is shaped. The tilt angle of is larger than the tilt angle of the covering thread in the general portion. The larger the inclination angle of the covering yarn with respect to the core yarn, the larger the amount of elongation of each yarn when the first yarn and the second yarn are pulled. Therefore, the elongation of the first yarn and the second yarn when the first yarn and the second yarn are pulled as the woven fabric base material is shaped and the bent portion is formed is allowed. .. Therefore, unlike the case where elongation is not allowed in the first yarn and the second yarn, it is possible to suppress the occurrence of meandering due to the difference in the path difference between the inside and the outside of the bend. As a result, the meandering of the first thread and the second thread can be suppressed without making the weaving composition different between the general portion and the bent portion, and the strength difference between the general portion and the bent portion can be reduced in the fiber reinforced composite material. ..

Further, regarding the fiber-reinforced composite material, the inclination angle is the one side and the hypotenuse in a triangle having the length of one pitch of the covering yarn as one side and the straight line where the covering yarn for one pitch is developed as the hypotenuse. The other side of the triangle having the inclination angle, which is the size of the angle sandwiched between the two, is the other side connecting the one side and the hypotenuse, and the elongation of the covering thread accompanying the shaping of the textile base material. Assuming that the amount is δ and the inclination angle θC of the covering thread with respect to the thread main shaft at the portion constituting the bent portion in the woven base material is the inclination angle θC, the inclination angle θC is determined. It may be calculated by the following equation (1).

これによれば、織物基材が賦形されたときの第１の糸及び第２の糸の伸び量は、カバーリング糸の傾斜角度によって決定される。カバーリング糸の傾斜角度が大きければ、伸び量も多くなる。そして、織物基材が賦形されたとき、糸が突っ張らずに、賦形を許容させるには、賦形に応じた第１の糸及び第２の糸の伸び量を確保する必要がある。第１の糸及び第２の糸の伸び量は、予め把握できる。そして、伸び量から傾斜角度θＣを算出するための（１）式を設定し、（１）式から算出された傾斜角度θＣでカバーリング糸を芯糸に巻き付けることにより、第１の糸及び第２の糸を所望する伸び量で伸ばすことができる。

According to this, the elongation amount of the first yarn and the second yarn when the woven fabric base material is shaped is determined by the inclination angle of the covering yarn. The larger the tilt angle of the covering yarn, the larger the amount of elongation. Then, when the woven fabric base material is shaped, it is necessary to secure the elongation amount of the first thread and the second thread according to the shaping in order to allow the shaping without the threads being stretched. The amount of elongation of the first thread and the second thread can be grasped in advance. Then, by setting the equation (1) for calculating the inclination angle θC from the elongation amount and winding the covering yarn around the core yarn at the inclination angle θC calculated from the equation (1), the first yarn and the first yarn are used. The yarn of 2 can be stretched by a desired amount of elongation.

The woven base material for solving the above problems includes a plurality of first threads arranged in parallel with each other and a plurality of second threads arranged in parallel with each other and in a direction intersecting with the first thread. It is a flat plate having a flat plate shape, and has a flat plate-shaped general portion and a bent portion that is bent or curved with respect to the general portion and has a surface intersecting with the surface of the general portion. The first thread and the second thread, which are woven base materials having a shape, include a core thread made of a reinforcing fiber and a covering thread spirally wound around the core thread. In the first thread and the second thread before the shape, the magnitude of the inclination of the covering yarn with respect to the yarn main shaft at the portion serving as the general portion is defined as the tilt angle θA, and the portion serving as the bending portion. Assuming that the magnitude of the inclination of the covering yarn with respect to the yarn main shaft is the inclination angle θB, the gist is that the inclination angle θB> the inclination angle θA is established.

The larger the inclination angle of the covering yarn with respect to the core yarn, the larger the amount of elongation when the first yarn and the second yarn are pulled. When the flat woven fabric base material is shaped to form a bent portion, the first thread and the second thread are stretched even if the first thread and the second thread are pulled. Therefore, in the first thread and the second thread, it is possible to suppress the occurrence of meandering in the bent portion due to the difference in the path difference due to bending. As a result, it is possible to reduce the difference in strength between the general portion and the bent portion in the woven fabric base material only by changing the inclination angle of the covering yarn.

Further, regarding the woven base material, in a triangle having the length of one pitch of the covering thread as one side and the straight line where the covering thread for one pitch is developed as the hypotenuse, the inclination angle is the one side and the hypotenuse. The size of the angle to be sandwiched, and the other side of the triangle having the inclination angle is the other side connecting the one side and the hypotenuse, and the amount of elongation of the covering thread accompanying the shaping of the textile base material. Let δ, and let the inclination angle θC be the magnitude of the inclination of the covering yarn with respect to the yarn main shaft at the portion constituting the bending portion before being shaped, the inclination angle θC is as follows. It may be calculated by the equation (2) of.

これによれば、織物基材が賦形されたときの第１の糸及び第２の糸の伸び量は、カバーリング糸の傾斜角度によって決定される。カバーリング糸の傾斜角度が大きければ、伸び量も多くなる。そして、織物基材が賦形されたとき、糸が突っ張らずに、賦形を許容させるには、賦形に応じた第１の糸及び第２の糸の伸び量を確保する必要がある。第１の糸及び第２の糸の伸び量は、予め把握できる。そして、伸び量から傾斜角度θＣを算出するための（２）式を設定し、（２）式から算出された傾斜角度θＣでカバーリング糸を芯糸に巻き付けることにより、第１の糸及び第２の糸を所望する伸び量で伸ばすことができる。

According to this, the elongation amount of the first yarn and the second yarn when the woven fabric base material is shaped is determined by the inclination angle of the covering yarn. The larger the tilt angle of the covering yarn, the larger the amount of elongation. Then, when the woven fabric base material is shaped, it is necessary to secure the elongation amount of the first thread and the second thread according to the shaping in order to allow the shaping without the threads being stretched. The amount of elongation of the first thread and the second thread can be grasped in advance. Then, by setting the equation (2) for calculating the inclination angle θC from the elongation amount and winding the covering yarn around the core yarn at the inclination angle θC calculated from the equation (2), the first yarn and the first yarn are used. The yarn of 2 can be stretched by a desired amount of elongation.

According to the present invention, the difference in strength between the general portion and the bent portion can be reduced.

The figure which shows typically the fiber-reinforced composite material. The perspective view which shows typically the 1st thread and the 2nd thread. (A) is a diagram showing the relationship between the yarn diameter of the core yarn and the inclination angle of the covering yarn, and (b) is a schematic diagram showing the yarn diameter of the core yarn and the pitch of the covering yarn. FIG. 1 is a cross-sectional view taken along the line AA of FIG. 1 schematically showing a part of a fiber-reinforced composite material. FIG. 1 is a sectional view taken along line BB of FIG. 1, schematically showing a part of a fiber-reinforced composite material. The figure which shows typically the woven fabric base material before shaping. FIG. 6 is a sectional view taken along line CC of FIG. 6 schematically showing a part of a woven fabric base material. FIG. 6 is a sectional view taken along line DD of FIG. 6 schematically showing a part of a woven fabric base material. FIG. 6 is a sectional view taken along line EE of FIG. 6 schematically showing a part of a woven fabric base material. A graph showing the relationship between the tilt angle and the amount of elongation.

Hereinafter, an embodiment in which the fiber-reinforced composite material and the woven fabric base material are embodied will be described with reference to FIGS. 1 to 10.
As shown in FIG. 1, the fiber-reinforced composite material 10 is formed by compounding a matrix resin 12 with a woven fabric base material 11 as a reinforcing base material. As the matrix resin 12, for example, an epoxy resin which is a thermosetting resin is used. The woven fabric base material 11 is formed by shaping a flat plate-shaped woven fabric base material 11. The woven fabric base material 11 has a first general portion 16 having a square annular shape in a plan view located on the outer peripheral side thereof, and a plane located in the central portion of the woven fabric base material 11 and at a position lower than the first general portion 16. The second general portion 17 having a rectangular shape and the bent portion 18 connecting the inner peripheral edge of the first general portion 16 and the outer peripheral edge of the second general portion 17 are continuous three-dimensional plates. Dot hatching is attached to the bent portion 18.

In the woven fabric base material 11, the bent portion 18 is bent or curved with respect to the first general portion 16 and the second general portion 17. The inner side surface 18a of the bent portion 18 intersects the surface 16a of the first general portion 16 and the surface 17a of the second general portion 17, and although not shown, the outer surface of the bent portion 18 is the first general portion. It intersects the back surface of 16 and the back surface of the second general portion 17.

The woven fabric base material 11 includes a plurality of first threads 21 arranged in parallel with each other, and a plurality of second threads 22 arranged in parallel with each other and in a direction intersecting with the first thread 21. In addition, in FIGS. 1 and 6, in order to make it easy to understand the positional relationship between the first thread 21 and the second thread 22, the adjacent first threads 21 and the second threads 22 are separated from each other. As shown in the figure, in reality, the adjacent first threads 21 and the second threads 22 are arranged in close proximity to each other. Further, in the present embodiment, the first thread 21 is a warp and the second thread 22 is a weft. The woven fabric base material 11 is a single-layer woven fabric formed by plain weaving a first thread 21 and a second thread 22.

As shown in FIG. 2, the first thread 21 and the second thread 22 each have a core thread 31 made of reinforcing fibers and a plurality of covering threads 32 spirally wound around the core thread 31. Be prepared. The core yarn 31 is a twisted yarn formed by twisting a plurality of discontinuous fibers. As the discontinuous fiber, an organic fiber or an inorganic fiber may be used, or a different kind of organic fiber, a different kind of inorganic fiber, or a mixed fiber obtained by mixing an organic fiber and an inorganic fiber may be used. .. Examples of the organic fiber include acrylic fiber, nylon fiber, polyester fiber, aramid fiber, poly-p-phenylene benzobisoxazole fiber, ultra-high molecular weight polyethylene fiber and the like, and examples of the inorganic fiber include carbon fiber, glass fiber and ceramic fiber. And so on. In the present embodiment, the core yarn 31 is formed by twisting carbon fibers.

The covering yarn 32 may use organic fibers or inorganic fibers, and examples of the organic fibers include acrylic fibers, nylon fibers, polyester fibers, aramid fibers, poly-p-phenylene benzobisoxazole fibers, and ultrahigh molecular weight polyethylene fibers. Examples of the inorganic fiber include carbon fiber, glass fiber, ceramic fiber and the like. In this embodiment, the covering yarn 32 is formed of carbon fiber.

The thread spindle L1 of the first thread 21 and the second thread 22 is the thread spindle of the core thread 31. In the first thread 21 and the second thread 22, the magnitude of the inclination of the thread spindle L2 (for example, see FIG. 4) of the covering thread 32 with respect to the thread spindle L1 is indicated by the inclination angle θ. The inclination angle θ is an acute angle among the angles formed between the yarn spindle L1 of the core yarn 31 and the yarn spindle L2 of the covering yarn 32.

As shown in FIGS. 3 (a) and 3 (b), it is assumed that the yarn diameter in a state where tension does not act on the first yarn 21 and the second yarn 22 and no elongation occurs is d0. The peripheral lengths of the first yarn 21 and the second yarn 22 in the state where no elongation has occurred are represented by πd0.

Further, in the covering yarn 32, the yarn spindle direction from a specific point on the circumference of the core yarn 31 to a specific point on the circumference when the covering yarn 32 extending spirally goes around the core yarn 31. Let the distance along the pitch be the pitch. In the covering yarn 32, the pitch of the covering yarn 32 becomes smaller as the inclination angle θ becomes larger. On the other hand, the smaller the inclination angle θ, the larger the pitch of the covering yarn 32.

The pitch of the covering yarn 32 in a state where the first yarn 21 and the second yarn 22 are not stretched is represented by P0, and the inclination angle is represented by θ0. The length of the covering yarn 32 at one pitch P0 in a state where the first yarn 21 and the second yarn 22 are not stretched is represented by the following formula A.

(Πd0) ² + P0 ² ... Equation A
On the other hand, the pitch of the covering yarn 32 in a state where the first yarn 21 and the second yarn 22 are stretched is represented by P1, and the inclination angle is represented by θ1. The length of the covering yarn 32 at one pitch P1 in a state where the first yarn 21 and the second yarn 22 are stretched is represented by the following formula B.

(Πd1) ² + P1 ² ... Equation B
When the first thread 21 and the second thread 22 are pulled and stretched, the covering thread 32 is fully stretched and stretched, and the first thread is in a state where the covering thread 32 is strongly wound around the core thread 31. Further elongation of 21 and the second thread 22 is restricted. When the elongation of the first yarn 21 and the second yarn 22 is restricted, the length of the covering yarn 32 at 1 pitch P0 when the elongation is not generated in the yarns 21 and 22 is the length of each yarn 21. , 22 is equal to the length of the covering yarn 32 at one pitch P1 when fully extended. Therefore, the following equation C holds.

(Πd1) ² + P1 ² = (πd0) ² + P0 ² ... Equation C
Next, the first thread 21 and the second thread 22 in the shaped woven fabric base material 11 will be described.

As shown in FIGS. 4 and 5, in the woven fabric base material 11, in the first general part 16 and the second general part 17, the first thread 21 and the second thread 22 are not shaped and go straight. It is not pulled. Therefore, it can be said that the formula A holds in the first general part 16 and the second general part 17. On the other hand, as shown in the dot hatching of FIG. 4, in the bent portion 18, the first thread 21 and the second thread 22 are pulled and stretched as the woven fabric base material 11 is shaped. Therefore, it can be said that the equation B holds in the bent portion 18.

As shown in FIG. 4, in the first thread 21 and the second thread 22, the portion constituting the first general portion 16 and the second general portion 17 and the portion constituting the bent portion 18 are covered with each other. The inclination angle θ of the thread 32 is different.

In the first thread 21 and the second thread 22, as the inclination angle θ of the covering thread 32 becomes larger, as shown by the solid line in FIG. 3B, the covering thread 32 is the thread main shaft of the core thread 31. The length of the covering thread 32 at one pitch is shortened because it approaches perpendicular to L1. The shorter the length of the covering yarn 32 at one pitch, the smaller the tightening force of the covering yarn 32 with respect to the core yarn 31.

On the other hand, as shown by the two-dot chain line in FIG. 3B, when the first thread 21 and the second thread 22 are pulled, the covering thread 32 is deformed so as to lengthen the pitch. Therefore, the first thread 21 and the second thread 22 can be stretched to some extent without being hindered by the covering thread 32. However, as described above, when the covering thread 32 is stretched and the formula C is established, the first thread 21 and the second thread 22 are in a fully stretched state, and the stretching is not allowed.

As shown in FIG. 4, in the woven fabric base material 11 after shaping, the inclination angle θA of the covering yarn 32 in the first general portion 16 and the second general portion 17 is set to the covering yarn in the bending portion 18. It is made smaller than the inclination angle θB of 32. That is, the inclination angle θB> the inclination angle θA is established.

Specifically, in the first general portion 16 located on one end side in the thread main axis direction in the cross section along the thread main axis direction of the first thread 21, the covering thread 32 of the first thread 21 is inclined. In the bent portion 18 which is wound around the core yarn 31 at an angle θA and is located on one end side in the yarn main axis direction, the covering yarn 32 of the first yarn 21 is wound around the core yarn 31 at an inclination angle θB. Further, in the second general portion 17, the covering yarn 32 of the first yarn 21 is wound around the core yarn 31 at an inclination angle θA, and in the bending portion 18 located on the other end side in the yarn main axis direction, the covering yarn is covered. 32 is wound around the core yarn 31 at an inclination angle θB. In the first general portion 16 located on the other end side in the yarn main axis direction, the covering yarn 32 of the first yarn 21 is wound around the core yarn 31 at an inclination angle θA.

Although not shown, even when the textile base material 11 is viewed in a cross section along the yarn spindle of the second yarn 22, the first general portion 16 located on one end side in the yarn spindle direction has a first position. The covering thread 32 of the thread 22 of 2 is wound around the core thread 31 at an inclination angle θA, and at the bending portion 18 located on one end side in the yarn spindle direction, the covering thread 32 is wound around the core thread 31 at an inclination angle θB. There is. Further, in the second general portion 17, the covering yarn 32 of the second yarn 22 is wound around the core yarn 31 at an inclination angle θA, and in the bent portion 18 located on the other end side in the yarn main axis direction, the second thread is second. The covering thread 32 of the thread 22 is wound around the core thread 31 at an inclination angle θB. In the first general portion 16 located on the other end side in the yarn main axis direction, the covering yarn 32 is wound around the core yarn 31 at an inclination angle θA.

Although not shown, in the portion of only the first general portion 16 in which the bending portion 18 does not exist, the covering yarn 32 is wound around the core yarn 31 of the first yarn 21 and the second yarn 22 at an inclination angle θA. ing.

Next, the woven fabric base material 11 before being shaped will be described.
As shown in FIG. 6, the woven fabric base material 11 has a flat plate shape. The woven fabric base material 11 is provided with a portion forming the first general portion 16 in a square annular shape on the outer peripheral portion, and a portion forming the bent portion 18 is square inside the portion forming the first general portion 16. Prepare for the ring. Further, the woven fabric base material 11 is provided with a portion forming the second general portion 17 in a rectangular shape inside the portion forming the bent portion 18.

In the woven fabric base material 11 before being shaped, when the woven fabric base material 11 is viewed in a cross section along the yarn spindle L1 of the first yarn 21, as shown in FIGS. 7 and 8, one end in the yarn spindle axis direction. In the portion serving as the first general portion 16 located on the side and the other end side, the covering yarn 32 of the first yarn 21 is wound around the core yarn 31 at an inclination angle θA.

The covering yarn 32 of the first yarn 21 is wound around the core yarn 31 at an inclination angle θC at the portion serving as the bent portion 18 located on one end side and the other end side in the yarn main axis direction. This inclination angle θC is larger than the inclination angle θB of the covering thread 32 in the bent portion 18 after shaping. That is, the covering thread 32 of the bent portion 18 has a smaller inclination angle θ than before the shaping due to the shaping.

Although not shown, the first general portion located on one end side and the other end side in the yarn spindle direction even when the woven fabric base material 11 is viewed in a cross section along the yarn spindle of the second yarn 22. At the portion 16, the covering thread 32 of the second thread 22 is wound around the core thread 31 at an inclination angle θA.

The covering yarn 32 of the second yarn 22 is wound around the core yarn 31 at an inclination angle θC at the portion serving as the bent portion 18 located on one end side and the other end side in the yarn main axis direction. This inclination angle θC is larger than the inclination angle θB of the covering thread 32 in the bent portion 18 after shaping.

As shown in FIG. 9, there is no portion that becomes the bent portion 18, and in the portion that becomes the first general portion 16, the covering yarn is compared with the core yarn 31 of the first yarn 21 and the second yarn 22. 32 is wound at an inclination angle θA.

Therefore, as the woven fabric base material 11 is shaped, the inclination angle θB of the covering yarn 32 in the bent portion 18 becomes smaller than the inclination angle θC before shaping. This is because the covering yarn 32 is also pulled by pulling the first yarn 21 and the second yarn 22 as the woven fabric base material 11 is shaped. The inclination angle θC of the covering thread 32 at the portion to be the bent portion 18 is larger than the inclination angle θA of the covering thread 32 at the portion to be the first general portion 16 and the second general portion 17. .. This indicates that the inclination angle θC of the covering yarn 32 before the woven fabric base material 11 is shaped is larger than the inclination angle θB of the covering yarn 32 at the bent portion 18 after shaping.

By increasing the inclination angle θC of the covering yarn 32, the covering even if the first yarn 21 and the second yarn 22 are pulled as the woven fabric base material 11 is shaped. It suppresses the elongation of the first yarn 21 and the second yarn 22 from being restricted by the yarn 32, and allows the first yarn 21 and the second yarn 22 to stretch.

In a state where the woven fabric base material 11 having the above configuration is shaped and the first general portion 16, the second general portion 17, and the bent portion 18 are formed, each yarn 21 and 22 of the bent portion 18 is a covering yarn. Although it is configured to include 32, it is longer than the threads 21 and 22 of the general parts 16 and 17. As a result, in each of the yarns 21 and 22 constituting the bent portion 18, the stretching by the covering yarn 32 is not hindered, and the meandering due to the shaping is suppressed.

Next, a method of obtaining the inclination angle θC set to develop the desired elongation with respect to the first yarn 21 and the second yarn 22 will be described.
The elongation of the covering thread 32 differs depending on the shape, bending method, size, and the like of the bent portion 18 of the woven fabric base material 11. Therefore, in the woven fabric base material 11, the amount of elongation required for the first and second threads 21 and 22 is set in advance according to the shape, bending method, size, and the like of the bent portion 18. Then, the inclination angle θC of the covering yarn 32 is calculated so that a desired elongation amount can be obtained. The inclination angle θC is calculated by the following equation (1).

なお、各糸２１，２２が伸びる前のカバーリング糸３２のピッチをＰ０とし、各糸２１，２２が伸びた後のカバーリング糸３２のピッチをＰ１とした場合、カバーリング糸３２の伸び量δは以下の式で表される。

When the pitch of the covering yarn 32 before the yarns 21 and 22 are stretched is P0 and the pitch of the covering yarn 32 after the yarns 21 and 22 are stretched is P1, the amount of elongation of the covering yarn 32 is set. δ is expressed by the following equation.

δ = P 1 / P 0 ... Equation Further, as shown in FIG. 3A, the inclination angle θ is such that the pitch length of the covering thread 32 is H1 on one side, and the covering thread 32 for one pitch is developed. It is the size of the angle sandwiched between one side H1 and the hypotenuse H2 in a right triangle whose straight line is the hypotenuse H2. The other side of the right triangle having the inclination angle θ is the other side H3 connecting one side H1 and the hypotenuse H2.

For example, in the bent portion 18, when the yarn diameters of the first yarn 21 and the second yarn 22 are 1 mm, the elongation amount is 1. To set in 2, the inclination angle θC of the covering yarn 32 before each yarn 21 and 22 is stretched is set to 76.2 degrees. Even when the yarn diameter is 2 mm or 3 mm, the inclination angle θC is calculated from the equation (1).

The relationship between the amount of elongation and the inclination angle θC is shown in the graph of FIG. In the graph of FIG. 10, the horizontal axis shows the amount of elongation, and the vertical axis shows the inclination angle θC. As shown in the graph of FIG. 10, the larger the elongation amount is set, the larger the inclination angle θC is. Therefore, it is shown that the larger the inclination angle θC of the covering yarn 32, the larger the elongation amount of each yarn 21 and 22 can be.

Next, a method for producing the fiber-reinforced composite material 10 will be described together with the operation of the present embodiment.
First, the flat woven fabric base material 11 is shaped to form a portion to be a first general portion 16, a second general portion 17, and a bent portion 18. When forming the bent portion 18, the first thread 21 and the second thread 22 constituting the bent portion 18 are pulled along with the shaping. At this time, the inclination angle θC of the covering thread 32 is preset so as to allow the extension of the first thread 21 and the second thread 22 due to the pulling. Therefore, the elongation of the first thread 21 and the second thread 22 is allowed. The first thread 21 and the second thread 22 constituting the first general portion 16 and the second general portion 17 hardly extend.

Then, the shaped woven fabric base material 11 is impregnated and cured with the matrix resin 12 to become a fiber reinforced composite material 10. The impregnation curing of the matrix resin 12 is performed by an RTM (resin transfer molding) method. By impregnating and curing the matrix resin 12 in the woven fabric base material 11, the first thread 21 and the second thread 22 of the woven fabric base material 11 are combined with the matrix resin 12 to form a fiber-reinforced composite material 10. The fiber-reinforced composite material 10 is used, for example, as an outer panel of a moving body such as an aircraft or a passenger car.

According to the above embodiment, the following effects can be obtained.
(1) In the woven fabric base material 11 constituting the fiber-reinforced composite material 10, the inclination angle θB of the covering yarn 32 in each yarn 21 and 22 constituting the bent portion 18 is set, and each yarn constituting the general portions 16 and 17 is set. It was made larger than the inclination angle θA of the covering thread 32 in 21 and 22. Therefore, even if the first thread 21 and the second thread 22 are configured such that the covering thread 32 is wound around the core thread 31, the first thread 21 and the second thread 22 are stretched when pulled for shaping the woven fabric base material 11. Is acceptable. As a result, unlike the case where elongation is not allowed in each of the yarns 21 and 22, it is possible to suppress the occurrence of meandering due to the difference in the path difference between the inside and the outside of the bending, and the general portions 16 and 17 are bent. The meandering of each thread 21 and 22 can be suppressed without making the weaving composition different from that of the portion 18, and the strength difference between the general portions 16 and 17 and the bent portion 18 can be reduced in the fiber reinforced composite material 10.

(2) The elongation amount of each of the yarns 21 and 22 is determined by the inclination angle θC of the covering yarn 32 before being shaped, and the larger the inclination angle θC, the larger the elongation amount. Then, in order to allow the shaping of the woven fabric base material 11, it is necessary to secure the elongation amount of each of the yarns 21 and 22 according to the shaping. The amount of elongation of each thread 21 and 22 can be grasped in advance. Then, the inclination angle θC for allowing the amount of elongation was calculated by the equation (1). Therefore, by using the yarns 21 and 22 in which the covering yarn 32 is wound around the core yarn 31 at the inclination angle θC calculated by using the equation (1), each yarn 21 that constitutes the bent portion 18 of the woven fabric base material 11 It is possible to suppress the occurrence of meandering in 22.

(3) In the woven fabric base material 11 before shaping, the inclination angle θC of the covering yarn 32 at the portion constituting the bent portion 18 is set, and the inclination of the covering yarn 32 at the portions constituting the general portions 16 and 17 is set. It was made larger than the angle θA. Therefore, when the woven fabric base material 11 is shaped to form the bent portion 18, the displacement of the covering yarn 32 allows the yarns 21 and 22 to stretch and suppresses the meandering of the yarns 21 and 22. The portion 18 can be formed.

(4) With a simple configuration of adjusting the inclination angle θ of the covering yarn 32 with respect to the core yarn 31, when the woven fabric base material 11 is shaped, the yarns 21 and 22 constituting the bent portion 18 meander. It can be suppressed from occurring.

(5) In the covering yarn 32, it is possible to suppress the meandering of each yarn 21 and 22 in the bent portion 18 of the woven fabric base material 11 only by locally adjusting the inclination angle θ only in the portion to be the bent portion 18. .. Therefore, as compared with the case where the woven structure is changed for each bent portion 18 of the woven fabric base material 11, the simple structure such as adjusting the inclination angle θ of the covering yarn 32 suppresses the occurrence of meandering of each yarn 21 and 22. can.

In addition, this embodiment can be changed and carried out as follows. The present embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.
○ In the woven fabric base material 11 after shaping, the inclination angle θA of the covering yarn 32 in the first general portion 16 and the second general portion 17 and the inclination angle θB of the covering yarn 32 in the bending portion 18 become equal. May be.

○ In the woven fabric base material 11, the shape and size of the bent portion 18 may be appropriately changed.
○ In the woven fabric base material 11, the first general part 16 may be omitted.
○ The calculation formula of the inclination angle θC may be an approximate formula obtained by multiplying the formula (1) by a coefficient.

○ The woven structure of the woven fabric base material 11 may be a satin weave or a twill weave other than the plain weave.
○ The woven fabric base material 11 is a multilayer in which a fiber layer formed by the first thread 21 and a fiber layer formed by the second thread 22 are laminated, and a plurality of fiber layers are restrained in the stacking direction by a restraining thread. It may be made of woven fabric.

○ The covering thread 32 may be a thread made of a fiber other than the reinforcing fiber.
Next, the technical idea that can be grasped from the above embodiment and another example will be added below.
(1) The pitch of the covering yarn before the first yarn and the second yarn are stretched is P0, and the pitch of the covering yarn after the first yarn and the second yarn are stretched is P0. When P1 is used, the elongation amount δ of the covering yarn is a woven fabric base material represented by the following formula.

δ = P 1 / P 0 ... Equation

10 ... Fiber reinforced composite material, 11 ... Textile base material, 12 ... Matrix resin, 16 ... First general part, 17 ... Second general part, 18 ... Bending part, 21 ... First thread, 22 ... Second Thread, 31 ... core thread, 32 ... covering thread

Claims (4)

The matrix resin is composited with a woven fabric base material having a plurality of first yarns arranged in parallel with each other and a plurality of second yarns arranged in parallel with each other and in a direction intersecting with the first yarn. It is a fiber reinforced composite material
The woven fabric base material has a flat plate-shaped general portion and a flat plate-shaped general portion.
It has a bent portion that is bent or curved with respect to the general portion and has a surface that intersects the surface of the general portion.
The first thread and the second thread include a core thread made of a reinforcing fiber and a covering thread spirally wound around the core thread.
In the first yarn and the second yarn, the magnitude of the inclination of the covering yarn with respect to the yarn spindle at the portion constituting the general portion is defined as the inclination angle θA, and the yarn at the portion constituting the bending portion. When the magnitude of the inclination of the covering yarn with respect to the main shaft is the inclination angle θB, the fiber reinforced composite material is characterized in that the inclination angle θB > the inclination angle θA is established. In a triangle whose one side is the length of one pitch of the covering thread and whose hypotenuse is the straight line where the covering thread for one pitch is developed, the inclination angle is the size of the angle sandwiched between the one side and the hypotenuse. The other side of the triangle having the inclination angle is the other side connecting the one side and the hypotenuse, and the elongation amount of the covering thread accompanying the shaping of the fabric base material is δ, and the fabric base. Assuming that the inclination angle θC of the covering yarn with respect to the yarn spindle at the portion constituting the bending portion before being shaped in the material, the inclination angle θC is calculated by the following equation (1). The fiber-reinforced composite material according to claim 1.

It is a flat plate having a plurality of first threads arranged parallel to each other and a plurality of second threads arranged parallel to each other and in a direction intersecting the first thread, and is shaped. A woven fabric base material having a flat plate-shaped general portion and a bent portion that is bent or curved with respect to the general portion and has a surface intersecting with the surface of the general portion.
The first thread and the second thread include a core thread made of a reinforcing fiber and a covering thread spirally wound around the core thread.
In the first thread and the second thread before shaping, the magnitude of the inclination of the covering yarn with respect to the yarn main shaft at the portion serving as the general portion is defined as the inclination angle θA, and the portion serving as the bending portion. The textile base material is characterized in that the inclination angle θB> the inclination angle θA is established, where the inclination angle θB is the magnitude of the inclination of the covering yarn with respect to the yarn main shaft of the yarn. In a triangle whose one side is the length of one pitch of the covering thread and whose hypotenuse is the straight line where the covering thread for one pitch is developed, the inclination angle is the size of the angle sandwiched between the one side and the hypotenuse. The other side of the triangle having the inclination angle is the other side connecting the one side and the hypotenuse, and the elongation amount of the covering thread accompanying the shaping of the fabric base material is δ, and the fabric base. Assuming that the inclination angle θC of the covering yarn with respect to the yarn spindle at the portion constituting the bending portion before being shaped in the material, the inclination angle θC is calculated by the following equation (2). The woven base material according to claim 3.

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