JP2021094699A - Fiber-reinforced composite material and manufacturing method of the same - Google Patents

Abstract

To reduce a difference in local properties of fiber-reinforced composite materials.SOLUTION: A fiber-reinforced composite material 10 is formed in a state where a UD tape is being woven into a tubular shape at a predetermined inclination angle. The fiber-reinforced composite material 10 is provided with a bent portion 20 that is bent with respect to an axial direction of the fiber-reinforced composite material 10. At an outer side P1 and an inner side P2 of the bent portion 20 on an outer surface of the fiber-reinforced composite material 10, inclination angles are configured to be identical.SELECTED DRAWING: Figure 1

Description

The present invention relates to a fiber-reinforced composite material and a method for producing a fiber-reinforced composite material.

Patent Document 1 describes a method for manufacturing a bent pipe.
As shown in FIG. 20, a mandrel 63 composed of an outer layer coating material 61 having elasticity and an internal filler 62 capable of changing the phase between a liquid phase and a solid phase is used. With the internal filler 62 in a solid phase, a filamentous prepreg is braided to the mandrel 63. In the molded body 64 obtained by braiding molding, the prepreg is woven so as to have a predetermined inclination angle with respect to the axial direction of the pipe.

As shown in FIG. 21, after making the mandrel 63 deformable into an arbitrary shape by using the internal filler 62 as a liquid phase, the molded body 64 is placed together with the mandrel 63 in the mold 65 in which the curved mold groove is formed. Place and cure the resin.

As shown in FIG. 22, the bent pipe 60 is manufactured by removing the internal filler and removing the mandrel 63.

Japanese Unexamined Patent Publication No. 2004-17412

In the method for manufacturing a bent pipe (fiber reinforced composite material) 60 of Patent Document 1, the molded body 64 is bent together with the mandrel 63 after performing braiding molding. Therefore, the inclination angle of the prepreg with respect to the axial direction of the bent pipe (fiber reinforced composite material) 60 is different between the outside and the inside of the bent portion, which is a local position on the outer surface of the bent pipe (fiber reinforced composite material) 60. It is easy to be in a state.

That is, as shown in FIG. 2, with respect to the inclination angle α1 of the prepreg (hereinafter, also referred to as “first UD tape”) 30a at a linear portion other than the bent portion, as shown in FIG. The inclination angle α2 of the first UD tape 30a on the outer side P1 tends to be small.

Further, as shown in FIG. 4, the inclination angle α3 of the first UD tape 30a on the inner side P2 of the bent portion tends to be larger than the inclination angle α1 of the first UD tape 30a.
Since the inclination angle of the first UD tape 30a is different between the outer side P1 and the inner side P2 of the bent portion, there is a problem that a difference in characteristics such as elastic modulus and strength is likely to occur between the outer side P1 and the inner side P2 of the bent part. Have.

Further, in the molded body 64 obtained by braiding molding of the bent pipe (fiber reinforced composite material) 60 of Patent Document 1, if the resin used for the molded body 64 is a thermoplastic resin, it has elasticity. There is also a problem in the heat resistance of the mandrel 63 composed of the outer layer coating material 61 and the inner filler 62 whose phase can be changed between the liquid phase and the solid phase. If, for example, a PEEK resin (polyetheretherketone resin) having a melting point of more than 300 ° C. is used as the thermoplastic resin, there is no mandrel that can cope with this.

The present invention has been made in view of such circumstances, and an object of the present invention is the production of a fiber-reinforced composite material having a bent portion and a fiber-reinforced composite material having a small difference in local characteristics and a fiber-reinforced composite material. To provide a method.

Another object of the present invention is to provide a fiber-reinforced composite material having the same effect even if the resin of the UD tape is a thermoplastic resin, and a method for producing the fiber-reinforced composite material.

The fiber-reinforced composite material for solving the above problems is a fiber-reinforced composite material formed in a state where the UD tape is woven into a tubular shape at a predetermined inclination angle, and the fiber-reinforced composite material is the fiber-reinforced composite material. It is a gist that the bent portion bent with respect to the axial direction of the material is provided, and the inclination angle is equally configured on the outside and the inside of the bent portion on the outer surface of the fiber reinforced composite material.

According to this configuration, the inclination angles are equal on the outside and the inside of the bent portion on the outer surface of the fiber reinforced composite material. Therefore, in the fiber-reinforced composite material having a bent portion, the difference in local characteristics can be reduced.

For the fiber-reinforced composite material, the inclination angle is preferably an angle within ± 6 ° within the range of 30 to 50 °. According to this configuration, the inclination angle of the UD tape is suitable for improving the characteristics of the fiber reinforced composite material.

Regarding the fiber-reinforced composite material, it is preferable that the resin impregnated in the UD tape is a thermoplastic resin. According to this configuration, it is easy to improve the moldability of the UD tape as compared with the embodiment in which the resin impregnated in the UD tape is a thermosetting resin, so that it is easy to improve the dimensional accuracy of the fiber reinforced composite material. Become.

In a method for manufacturing a fiber-reinforced composite material for solving the above problems, a UD tape is formed in a state of being woven into a tubular shape at a predetermined inclination angle, and a bent portion bent in the axial direction and a bent portion along the axial direction. A method for manufacturing a fiber-reinforced composite material including at least one of a tapered portion having a large outer diameter, wherein a plurality of mandrel members are connected to form at least one of a plurality of bent portions and a plurality of tapered portions. A mandrel assembling step for assembling a mandrel including the above, a braiding molding step for performing braiding molding on the mandrel obtained in the mandrel assembling step using UD tape, and a molded body obtained in the braiding molding step. The gist is to have a cutting step of cutting and a decentering step of pulling out the mandrel from the cut molded body.

According to this configuration, by performing braiding molding using a mandrel having a plurality of bent portions, the inclination angle of the UD tape can be made equal between the outside and the inside of the bent portion on the outer surface of the fiber reinforced composite material. it can. Therefore, it is possible to manufacture a fiber-reinforced composite material having a bent portion and having a small difference in local characteristics.

Further, by performing braiding molding using a mandrel having a plurality of bent portions and a plurality of tapered portions, a plurality of braiding moldings are performed by individually using a mandrel having a bent portion and a tapered portion. The molded product can be continuously molded at a relatively short distance. Therefore, the material loss that occurs in the cutting process can be suppressed.

Regarding the method for producing the fiber-reinforced composite material, a resin film is wound around the surface of the molded product obtained in the braiding molding step, a high shrinkage tape is wound around the surface of the resin film, and then heat treatment is performed. It is preferable to have an impregnation step of impregnating the molded product with the resin constituting the resin film. According to this configuration, the contact points between the UD tapes can be more preferably fixed by the resin impregnated in the molded product. Further, since the braided gap created by braiding the UD tape can be filled with the resin constituting the resin film, the surface of the molded product can be made smoother.

Regarding the method for producing the fiber-reinforced composite material, it is preferable to move the mandrel by an automatic feeding means so that the mandrel is always located at a position where the braiding molding is performed in the braiding molding step. According to this configuration, braiding molding can be performed in a more stable state as compared with the mode in which the mandrel is manually moved.

According to the present invention, it is possible to reduce the difference in local characteristics in the fiber-reinforced composite material having a bent portion.

The perspective view of the fiber reinforced composite material of 1st Embodiment. The plan view of the linear part of the fiber reinforced composite material of 1st Embodiment. Top view of the outside of the bent portion in the conventional fiber reinforced composite material. Top view of the inside of the bent portion in the conventional fiber reinforced composite material. The perspective view of the mandrel member of 1st Embodiment. FIG. 3 is a cross-sectional view of the mandrel member of the first embodiment. The perspective view of the joint of 1st Embodiment. FIG. 3 is a cross-sectional view of the joint of the first embodiment. Sectional drawing of the mandrel of 1st Embodiment. A side view of the mandrel of the first embodiment. Schematic diagram of the braiding device viewed from the side. Schematic diagram of the braiding device in a plan view. The perspective view of the fiber reinforced composite material of 2nd Embodiment. The perspective view of the mandrel member of the 2nd Embodiment. FIG. 3 is a cross-sectional view of the mandrel member of the second embodiment. The perspective view of the joint of the 2nd Embodiment. FIG. 3 is a cross-sectional view of the joint of the second embodiment. Sectional drawing of the mandrel of the 2nd Embodiment. A side view of the mandrel of the second embodiment. Sectional drawing of the braiding molded article of the prior art. A perspective view of a mold for bending a conventional technique. Perspective view of a conventional bent pipe. Perspective view of another prior art mandrel member. Side view of another prior art mandrel member. FIG. 3 is a cross-sectional view of a mandrel member and a molded body in braiding molding using another conventional mandrel member.

(First Embodiment)
The first embodiment of the fiber reinforced composite material will be described.
As shown in FIGS. 1 and 2, the fiber-reinforced composite material 10 is formed by weaving a UD tape 30 into a tubular shape. In the cross section orthogonal to the axial direction of the fiber-reinforced composite material 10, the outer peripheral shape of the fiber-reinforced composite material 10 is circular, and the inner peripheral shape is also circular.

The fiber-reinforced composite material 10 has a bent portion 20 that is bent in the axial direction. The bent portion 20 is provided at the central portion in the longitudinal direction of the fiber reinforced composite material 10. The bending angle β of the bent portion 20 is not particularly limited, but is preferably 2 to 30 °, and more preferably 3 to 20 °. Here, the bending angle β is the first axial direction D1 which is the axial direction from the end portion 10a on one end side of the fiber reinforced composite material 10 toward the bending portion 20, and the other end side of the fiber reinforced composite material 10 from the bending portion 20. It is assumed that it means the angle formed by the second axial direction D2, which is the axial direction toward the end portion 10b of. In other words, the first axial direction D1 and the second axial direction D2 of the fiber reinforced composite material 10 intersect in a state of being inclined by the bending angle β.

The UD tape 30 is woven in a state of being oriented so as to have a predetermined inclination angle with respect to the axial direction of the fiber reinforced composite material 10. Here, the UD tape 30 means a tape formed by impregnating a resin with a plurality of fibers oriented in one direction.

The resin constituting the UD tape 30 is not particularly limited, and known thermosetting resins and thermoplastic resins can be used. As the resin constituting the UD tape 30, a thermoplastic resin is preferable because it is easier to improve the moldability of the UD tape 30 as compared with a thermosetting resin.

The thermosetting resin used for the UD tape 30 is not particularly limited, and an epoxy resin, a polyester resin, a phenol resin, or the like can be used. The thermoplastic resin used for the UD tape 30 is not particularly limited, and is a polypropylene resin, a nylon resin (hereinafter, also referred to as "polyetheretone resin"), an acrylonitrile-butadiene-styrene copolymer resin (hereinafter, "ABS resin"". Also referred to as), polyetheretherketone resin (hereinafter, also referred to as “PEEK resin”) and the like can be used. Among them, polyamide resin and PEEK resin are preferable because they are easy to mold. Further, PEEK resin is more preferable because it has excellent heat resistance.

The fibers oriented in one direction in the UD tape 30 are not particularly limited, and known fibers used for the fiber-reinforced composite material can be used. Examples of the fiber used in the UD tape 30 include carbon fiber and glass fiber. Among them, carbon fiber is preferable because it has excellent properties such as tensile elastic modulus and tensile strength.

The length of the UD tape 30 is not particularly limited, and is preferably 20 m or more, and more preferably 30 to 200 m.
The thickness of the UD tape 30 is not particularly limited, and is preferably 0.1 to 0.5 mm, more preferably 0.1 to 0.3 mm.

The width of the UD tape 30 is not particularly limited, and is preferably 1.0 to 10 mm. Above all, in the case of PEEK resin, it is more preferably 1.5 to 3 mm.
However, the UD tape 30 is impregnated with fibers oriented in one direction by a resin, and the form thereof is the width of the UD tape 30 shown above by slitting a sheet having a width of 50 to 300 mm. May have.

FIG. 2 shows a plan view of the fiber reinforced composite material 10.
In FIG. 2, the left-right direction is the axial direction of the fiber-reinforced composite material 10, the left side of FIG. 2 is one end side of the fiber-reinforced composite material 10, and the right side is the other end side of the fiber-reinforced composite material 10. With reference to the central portion M in the radial direction of the fiber-reinforced composite material 10, the axial direction toward the other end side of the fiber-reinforced composite material 10 is 0 °. The inclination angle of the left side (upper side of FIG. 2) with respect to the other end side of the fiber reinforced composite material 10 from the central portion M is represented by a positive angle, and the right side with respect to the other end side of the fiber reinforced composite material 10 (FIG. 2). The tilt angle (lower side) is represented by a negative angle.

As shown in FIG. 2, the fiber-reinforced composite material 10 has a first UD tape 30a inclined to the left side with respect to the axial direction of the fiber-reinforced composite material 10 at an inclination angle α1, and the fiber-reinforced composite material 10 with respect to the axial direction. It has a second UD tape 30b inclined at an inclination angle −α1 on the right side. The first UD tape 30a and the second UD tape 30b are braided as described later.

When the fiber-reinforced composite material 10 is viewed in a plan view, the first UD tape 30a and the second UD tape 30b are formed in a curved shape having a larger curvature toward the outer side in the radial direction of the fiber-reinforced composite material 10, but are straight from the central portion M. The tilt angle shall be determined on the assumption that it extends in a shape.

The inclination angle α1 of the first UD tape 30a is not particularly limited, but is preferably in the range of 30 to 50 °, and more preferably in the range of 35 to 45 °.
The inclination angle −α1 of the second UD tape 30b is preferably configured in the same manner except that the inclination angle α1 of the first UD tape 30a is opposite to the inclination angle α1.

The fiber-reinforced composite material 10 is a third UD tape (not shown) which is a UD tape 30 extending along the axial direction of the fiber-reinforced composite material 10 as a central thread, and / or in the axial direction of the fiber-reinforced composite material as a central thread. It has metal fibers (not shown) that extend along it.

The metal fiber is not particularly limited, and a stainless steel fiber can be used.
As will be described later, braiding molding is performed so that the third UD tape and / or the metal fiber extends along the axial direction while the first UD tape 30a and the second UD tape 30b have predetermined inclination angles α1 and −α1. As a result, the first UD tape 30a, the second UD tape 30b, and the central yarn are woven into a tubular shape.

As shown in FIG. 2, in the fiber-reinforced composite material 10 of the present embodiment, the inclination angle α1 of the first UD tape 30a at a linear portion other than the bent portion 20 is the first at the outer P1 and the inner P2 of the bent portion 20. It is configured to be equal to the inclination angle of the 1UD tape 30a. Further, the inclination angle −α1 of the second UD tape 30b at a linear portion other than the bent portion 20 is configured to be equal to the inclination angle of the second UD tape 30b at the outer P1 and the inner P2 of the bent portion 20.

As shown in FIG. 1, the outer side P1 of the bent portion 20 means the side opposite to the bent center side of the bent portion 20 on the outer surface of the fiber reinforced composite material 10. The inner side P2 of the bent portion 20 means the bent center side of the bent portion 20 on the outer surface of the fiber reinforced composite material 10.

The inclination angle α1 of the first UD tape 30a at a linear portion other than the bent portion 20 is configured to be equal to the inclination angle of the first UD tape 30a at the outer P1 and the inner P2 of the bent portion 20, except for the bent portion 20. It is assumed that the inclination angles of the first UD tape 30a are aligned at the linear portion of the above, the outer side P1 of the bent portion 20, and the inner P2 of the bent portion 20.

Similarly, the inclination angle −α1 of the second UD tape 30b at a linear portion other than the bent portion 20 is configured to be equal to the inclination angle of the second UD tape 30b at the outer P1 and the inner P2 of the bent portion 20. It is assumed that the inclination angles of the second UD tape 30b are aligned at the linear portion other than the bent portion 20, the outer side P1 of the bent portion 20, and the inner P2 of the bent portion 20.

In other words, the fiber-reinforced composite material 10 of the present embodiment is configured such that the inclination angle of the first UD tape 30a is constant at any of the linear portion, the outer side P1 of the bent portion 20, and the inner P2 of the bent portion 20. The inclination angle of the second UD tape 30b is made constant.

The state in which the inclination angles of the first UD tape 30a are uniform is not particularly limited, but any of the linear portion, the outer side P1 of the bent portion 20, and the inner P2 of the bent portion 20 of the first UD tape 30a. The difference in inclination angles ((α1-α2) and (α1-α3)) is preferably within ± 3 °, and more preferably within ± 2 °. It is preferable that the inclination angle −α1 of the second UD tape 30b is similarly configured.

In other words, the inclination angle α1 of the first UD tape 30a and the inclination angle −α1 of the second UD tape 30b are set at any of the linear portion, the outer side P1 of the bent portion 20, and the inner P2 of the bent portion 20. The angle is preferably within ± 6 °, more preferably within ± 4 °.

The method for producing the fiber-reinforced composite material 10 of the first embodiment will be described.
The fiber-reinforced composite material 10 is manufactured by going through the mandrel assembly step, the braiding molding step, the impregnation step, the cutting step, and the decentering step described below in this order.

(Mandrel assembly process)
The mandrel assembly step is a step of connecting a plurality of mandrel members to assemble a mandrel having a plurality of bent portions.

As shown in FIGS. 5 and 6, the mandrel member 40 is formed in a columnar shape. Inclined surfaces 40a are formed at both ends of the mandrel member 40 with respect to a cross section orthogonal to the axial direction of the mandrel member 40. An insertion hole 40b into which a joint is inserted is provided in the center of both inclined surfaces 40a along the axial direction.

Here, the inclination angle of the inclined surface 40a is set to β / 2 with respect to the bending angle β of the bending portion 20 shown in FIG.
As shown in FIGS. 7 to 9, the plurality of mandrel members 40 are connected via a joint 41 inserted into the insertion hole 40b. The joint 41 is formed in a columnar shape, and a bent portion 41a is provided at a central portion in the axial direction. The bending angle γ at the bending portion 41a of the joint 41 is configured to be equal to the bending angle β of the bending portion 20 of the fiber reinforced composite material 10.

The material of the mandrel member 40 is not particularly limited, and a known material used for the mandrel 42 can be adopted. As the material of the mandrel member 40, steel is mainly used, and for example, carbon steel, stainless steel and the like can be used. The material of the joint 41 is not particularly limited, but it is preferably the same material as the mandrel member 40.

As shown in FIG. 9, one end side of the joint 41 is inserted into the insertion hole 40b of one mandrel member 40, and the other end side of the joint 41 is inserted into the insertion hole 40b of the other mandrel member 40. The mandrel member 40 is connected. The two mandrel members 40 are configured to have the same shape, and the two mandrel members 40 are connected to one mandrel member 40 in a state where the other mandrel member 40 is rotated by 180 ° in the circumferential direction.

As shown in FIG. 10, by connecting a plurality of mandrel members 40 in the same manner, a mandrel 42 having a plurality of bent portions 42a is assembled.
(Brading molding process)
The braiding molding step is a step of weaving the UD tape 30 into a tubular shape using the braiding device 50 with respect to the mandrel 42 obtained in the assembling step.

As shown in FIGS. 11 and 12, the mounting table 51 is provided with a storage groove 51a, and the mandrel 42 is mounted in a state of being housed in the storage groove 51a. The width of the accommodating groove 51a is larger than the width direction of the mandrel 42, and the mandrel 42 is accommodated in the accommodating groove 51a in a loosely fitted state.

Here, as shown in FIG. 10, the dimension in the width direction of the mandrel 42 is the dimension in the direction orthogonal to the longitudinal direction, which is the direction in which the mandrel 42 extends, and is the length between the vertices of the adjacent bent portions 42a. It shall mean T.

As shown in FIG. 11, a push rod 52 for moving the mandrel 42 toward the braiding device 50 is arranged at the rear end of the mandrel 42 in the accommodating groove 51a. A driving device 54 for moving the push rod 52 at a predetermined speed is attached to the mounting table 51. When the push rod 52 is moved by the drive device 54, the rear end portion of the mandrel 42 is pushed, so that the mandrel 42 automatically moves with respect to the braiding device 50. Therefore, the push rod 52 and the drive device 54 function as an automatic feed device that automatically moves the mandrel 42.

As shown in FIGS. 11 and 12, while the mandrel 42 is automatically moved and passed through the braiding device 50, the first UD tape 30a, the second UD tape 30b, and the third UD tape 30c as the central thread are used with respect to the mandrel 42. , And the metal fiber 31 as the central yarn is used for braiding molding.

The first UD tape 30a and the second UD tape 30b are supplied from the bobbin 50a provided in the braiding device 50 through the carrier 50b and are woven in the braided portion A.

When braiding is performed, tension is applied to the mandrel 42 from the first UD tape 30a and the second UD tape 30b. This tension is applied substantially evenly to the entire circumference of the mandrel 42 from the outside in the radial direction.

Since the mandrel 42 is loosely fitted in the accommodating groove 51a, it is configured so that the orientation of the mandrel 42 in the longitudinal direction can be changed according to the tension from the first UD tape 30a and the second UD tape 30b. In the braided portion A in which the mandrel 42 is braided, tension is applied substantially evenly from the outside in the radial direction, so that the axial direction of the mandrel 42 is along the transport direction of the mandrel 42. As a result, even when braiding molding is performed on the bent portion 42a of the mandrel 42, the axial direction of the mandrel 42 is in a state of being along the transport direction of the mandrel 42. In other words, braiding molding is always performed with the mandrel 42 centered.

The molded body 53 obtained by braiding molding is gripped (chucked) by a gripping device 55 arranged in front of the molded body 53 in the transport direction. The gripping device 55 is mounted on the moving belt 56 and is configured to be able to move in the transport direction in accordance with the movement of the moving belt 56. By moving the gripping device 55, the molded body 53 can be pulled out along the transport direction. The moving speed of the gripping device 55 is configured to be substantially equal to the moving speed of the push rod 52 that pushes the rear end of the mandrel 42.

(Immersion process)
In the impregnation step, a resin film is wound around the surface of the molded product 53 obtained in the braiding molding step, a high shrinkage tape is wound around the surface of the resin film, and then heat treatment is performed to form a resin film. Is a step of impregnating the molded product 53.

The resin film is not particularly limited, and known thermosetting resins and thermoplastic resins can be used. A thermoplastic resin is preferable as the resin film because it is easier to impregnate than a thermosetting resin. It is preferable that the resin film is the same resin as the resin constituting the UD tape 30 because it is easy to uniformly impregnate the molded body 53.

The high shrinkage tape is not particularly limited, and a known high shrinkage tape can be used. The high shrinkage tape is preferably made of a polyimide resin that does not easily melt by heating. For example, it is preferable to use "HI-SHRINKTAPE" which is a heat shrinkage film manufactured by DUNSTONE.

As the heat treatment conditions, the conditions under which the UD tape 30 can be impregnated with the resin constituting the resin film can be appropriately selected. As the conditions of the heat treatment, for example, it is preferable to heat at 380 to 450 ° C., and more preferably 400 to 430 ° C. in an air atmosphere. Further, it is preferable to heat at the above heating temperature for 1 to 4 minutes, and more preferably to heat for 2 to 3 minutes. After the heat treatment, the high shrinkage tape is peeled off and removed.

(Cutting process)
The cutting step is a step of cutting the molded body 53 obtained in the braiding molding step to a predetermined length.

As shown in FIG. 10, only the molded body 53 is cut without cutting the mandrel member 40 so that the portion indicated by the arrow C in the mandrel 42 becomes the cutting portion.
(Decore process)
The decentering step is a step of pulling out the mandrel 42 from the molded product cut in the cutting step. Decentering is performed by pulling out the other end of the molded body and the mandrel 42 on the cut surface while grasping one end of the molded body and the mandrel 42 on the cut surface.

By going through the above steps in order, the fiber-reinforced composite material 10 of the present embodiment can be obtained.
The application of the fiber-reinforced composite material 10 is not particularly limited, and the fiber-reinforced composite material 10 having a bent portion 20 can be appropriately used for known applications. Applications of the fiber-reinforced composite material 10 having the bent portion 20 include, for example, a gamma-type nail device attached to the bone marrow cavity.

The operation of the first embodiment will be described.
In the fiber-reinforced composite material 10 manufactured by the conventional manufacturing method, the molded body 64 is bent after performing braiding molding.

Therefore, as shown in FIG. 3, the inclination angle α2 of the first UD tape 30a and the inclination angle −α2 of the second UD tape 30b on the outer side P1 of the bent portion 20 are linear portions other than the bent portion 20 (FIG. 2). (See), the inclination angle α1 of the first UD tape 30a and the inclination angle −α1 of the second UD tape 30b tend to be smaller. That is, since the force is applied to the outer side P1 of the bent portion 20 so as to be pulled in the axial direction, the UD tape 30 is likely to be oriented along the axial direction of the fiber reinforced composite material 10.

Further, on the outer side P1 of the bent portion 20, the distance between the third UD tapes and / or the distance between the metal fibers tends to be large.
Further, as shown in FIG. 4, the inclination angle α3 of the first UD tape 30a and the inclination angle −α3 of the second UD tape 30b on the inner side P2 of the bent portion 20 are linear portions other than the bent portion 20 (FIG. 2). (See), the inclination angle α1 of the first UD tape 30a and the inclination angle −α1 of the second UD tape 30b tend to be larger. That is, since the force is applied to the inner P2 of the bent portion 20 so as to be compressed in the axial direction, the UD tape 30 is likely to be oriented along the radial direction of the fiber reinforced composite material 10.

Further, in the inner P2 of the bent portion 20, the distance between the third UD tapes and / or the distance between the metal fibers tends to be small, and in some cases, meandering may occur.
As described above, the elastic modulus and the elastic modulus between the outer P1 and the inner P2 of the bent portion 20 are different because the inclination angle of the UD tape 30 is different between the outer P1 and the inner P2 of the bent portion 20 and the spacing between the central threads is different. Differences in characteristics such as strength are likely to occur.

On the other hand, as shown in FIG. 2, the fiber-reinforced composite material 10 of the present embodiment is always braided with the mandrel 42 centered using the mandrel 42 having the bent portion 42a in advance. ing. Therefore, the inclination angle of the UD tape 30 at the outer side P1 and the inner side P2 of the bent portion 20 is equal to the inclination angle of the UD tape 30 at the linear portion other than the bent portion 20. Further, the distance between the central threads at the outer side P1 and the inner side P2 of the bent portion 20 is also equal to that of the linear portion other than the bent portion 20. Naturally, the meandering of the central thread is not observed.

The effect of the first embodiment will be described.
(1) The inclination angle α1 of the first UD tape 30a is equally configured and the inclination angle −α1 of the second UD tape 30b is equally configured on the outer P1 and the inner P2 of the bent portion 20 on the outer surface of the fiber reinforced composite material 10. ing. Therefore, in the fiber-reinforced composite material 10 having the bent portion 20, the difference in local characteristics can be reduced.

The term "local" means an arbitrary region in which the range of the linear portion of the fiber-reinforced composite material 10, the outer side P1 of the bent portion 20, the inner side P2 of the bent portion 20, and the like is limited. In addition, local characteristics include elastic modulus, strength, and the like. The strength means bending strength, compressive strength, and the like. Further, the difference in local characteristics does not include the difference in characteristics derived from the shape itself of the fiber reinforced composite material 10.

(2) The inclination angle α1 of the first UD tape 30a and the inclination angle −α1 of the second UD tape 30b are angles within ± 6 ° within the range of 30 to 50 °. Therefore, the inclination angle of the UD tape 30 is suitable for improving the characteristics of the fiber-reinforced composite material 10.

(3) The resin impregnated in the UD tape 30 is a thermoplastic resin. Therefore, as compared with the embodiment in which the resin impregnated in the UD tape 30 is a thermosetting resin, the moldability of the UD tape 30 can be easily improved, so that the dimensional accuracy of the fiber reinforced composite material 10 can be easily improved. ..

(4) Braiding molding is performed with the mandrel 42 centered.
The inclination angle of the UD tape 30 can be made equal to the bent portion 42a of the mandrel 42 at the outer P1 and the inner P2 of the bent portion 20. Therefore, it is possible to manufacture the fiber-reinforced composite material 10 having a small difference in local characteristics.

(5) Braiding molding is performed using a mandrel 42 having a plurality of bent portions 42a. Therefore, unlike the prior art, it is not necessary to use the mandrel 63 composed of the outer layer coating material 61 having elasticity and the internal filler 62 capable of changing the phase between the liquid phase and the solid phase. Since a mandrel having high heat resistance can be used, braiding molding can be preferably performed even when a thermoplastic resin having a high melting point such as PEEK resin is used.

(6) A resin film is wound around the surface of the molded product 53 obtained in the braiding molding step, a high shrinkage tape is wound around the surface of the resin film, and then heat treatment is performed to obtain a resin constituting the resin film. It has an impregnation step of impregnating the molded body 53. Therefore, the contact points between the UD tapes 30 can be more preferably fixed by the resin impregnated in the molded body 53. Further, since the braided gap created by braiding the UD tape 30 can be filled with the resin constituting the resin film, the surface of the molded body 53 can be made smoother.

(7) In the braiding molding step, the mandrel 42 is moved by the automatic feeding means so that the mandrel 42 is always positioned at the position where the braiding molding is performed. Therefore, the braiding molding can be performed in a more stable state as compared with the mode in which the mandrel 42 is manually moved.

(Second Embodiment)
The second embodiment of the fiber reinforced composite material 10 will be described.
As shown in FIG. 13, the fiber-reinforced composite material 10 of the second embodiment is formed by weaving a UD tape into a tubular shape. In the cross section orthogonal to the axial direction of the fiber-reinforced composite material 10, the outer peripheral shape of the fiber-reinforced composite material 10 is circular, and the inner peripheral shape is also circular. The fiber-reinforced composite material 10 includes a tapered portion 21 whose outer diameter increases along the axial direction. Specifically, the diameter L1 of the end portion 10a on one end side in the axial direction of the fiber reinforced composite material 10 is configured to be larger than the diameter L2 of the end portion 10b on the other end side in the axial direction of the fiber reinforced composite material 10. There is. The fiber-reinforced composite material 10 is configured such that the diameter gradually increases from the end on the other end side to the end on the one end side in the entire axial direction. In other words, the entire fiber-reinforced composite material 10 is configured to have a tapered shape.

The diameter L1, the diameter L2, and the length L3 of the tapered portion are not particularly limited, but the taper ratio; the value of (L1-L2) / L3 is preferably 0.001 to 0.200, and is 0. More preferably, it is .03 to 0.100.

The inclination angles of the first UD tape 30a are the same at the distal end side P3 and the proximal end side P4 of the tapered portion 21 along the axial direction of the fiber reinforced composite material 10. Similarly, the inclination angles of the second UD tape 30b are the same at the distal end side P3 and the proximal end side P4 of the tapered portion 21 along the axial direction of the fiber reinforced composite material 10.

Here, the tip end side P3 of the tapered portion 21 means one end side of the fiber reinforced composite material 10 with respect to the central portion in the axial direction, and the proximal end side P4 of the tapered portion 21 is the axial direction of the fiber reinforced composite material 10. It shall mean the other end side from the central part.

The method for producing the fiber-reinforced composite material 10 of the second embodiment will be described.
Since the manufacturing method of the second embodiment is the same step as that of the manufacturing method of the first embodiment except that the shape of the mandrel is different, the description other than the mandrel assembly step will be omitted.

(Mandrel assembly process)
As shown in FIGS. 14 and 15, the mandrel member 43 is formed in a columnar shape. Both ends of the mandrel member 43 have a tapered shape with an outer diameter smaller than that of the central portion of the mandrel member 43. In other words, a tapered portion 43a whose outer diameter decreases from the central portion of the mandrel member 43 toward both ends is formed. At both ends of the mandrel member 43, outer diameters are smaller than those of the tapered portion 43a, and protruding portions 43b protruding outward in the axial direction are formed.

As shown in FIGS. 16 to 18, the plurality of mandrel members 43 are connected via joints 44 attached to both ends. The joint 44 is formed in a columnar shape, and holes 44a extending in the axial direction are formed on both end faces in the axial direction.

As shown in FIG. 18, the protruding portion 43b on the other end side of one mandrel member 43 is inserted into the hole 44a on one end side of the joint 44, and the other mandrel member is inserted into the hole 44a on the other end side of the joint 44. The two mandrel members 43 are connected by inserting the protrusion 43b on one end side of the 43.

As shown in FIG. 19, by connecting the plurality of mandrel members 43 in the same manner, the mandrel 45 having the plurality of tapered portions 43a is assembled.
In the cutting step, only the molded body is cut at the position indicated by the arrow C in FIG. 19, and then in the decentering step of pulling out the mandrel from the cut molded body, the obtained molded body is obtained after removing the mandrel. , The fiber-reinforced composite material 10 provided with the tapered portion 21 is manufactured by cutting at the portion indicated by the arrow C'in FIG.

The operation of the second embodiment will be described.
In the conventional method for manufacturing a fiber-reinforced composite material having a tapered portion, as shown in FIGS. 23 and 24, the tapered portion 43a'which is configured to have a thick one end side and a small outer diameter toward the other end side to have a tapered shape is formed. The formed mandrel member 43'is used.

As shown in FIG. 25, braiding molding is performed using a plurality of mandrel members 43'individually to produce a straight tube tapered molded body 53', and then the molded body 53'is cut by an arrow C in FIG. 25. Further, only the molded product was cut with the arrow C', and then it was manufactured through a decentering step. Such a manufacturing method has a problem that the distance between the molded bodies at the time of molding tends to be relatively large, and the material loss in the cutting process increases.

On the other hand, the fiber-reinforced composite material 10 of the present embodiment is braided by using a mandrel 45 having a plurality of tapered portions 43a in advance. Therefore, the inclination angle of the first UD tape 30a and the inclination angle of the second UD tape 30b in the tapered portion 43a are the inclination angle α1 of the first UD tape 30a and the inclination angle −α1 of the second UD tape 30b at the linear portion. Is equal to.

Further, as compared with the embodiment in which the mandrel member 43'provided with the tapered portion 43a' is individually used for braiding molding, the second embodiment continuously molds a plurality of molded bodies at a relatively short distance. be able to.

According to the second embodiment, the following effects can be obtained in addition to the effects (2) to (7) of the first embodiment.
(8) The inclination angle of the first UD tape 30a is equal to that of the distal end side P3 and the proximal end side P4 along the axial direction of the tapered portion 21, and the inclination angles of the second UD tape 30b are equal to each other. Therefore, in the fiber-reinforced composite material 10 having the tapered portion 21, the difference in local characteristics can be reduced.

(9) Since the braiding molding is performed by using the mandrel 45 having the plurality of tapered portions 43a in advance, the braiding molding is performed by individually using the mandrel member 43' provided with the tapered portions 43a'. A plurality of molded bodies can be continuously molded at a relatively short distance. Therefore, the material loss that occurs in the cutting process can be suppressed.

Similarly, also in the first embodiment, since the braiding molding is performed using the mandrel 42 provided with the plurality of bent portions 42a, the braiding molding is performed by individually using the mandrel members provided with the bent portions. Therefore, the material loss that occurs in the cutting process can be suppressed.

The first embodiment and the second embodiment can be modified and implemented as follows. The first embodiment, the second embodiment, and the following modified examples can be implemented in combination with each other within a technically consistent range.

-In the first embodiment, the bent portion 20 is provided at the central portion in the longitudinal direction of the fiber reinforced composite material 10, but the present invention is not limited to this embodiment. The bent portion 20 may be provided on one end side of the central portion in the longitudinal direction of the fiber reinforced composite material 10 or on the other end side of the central portion. The fiber reinforced composite material 10 may be provided in a curved shape as a whole in the longitudinal direction.

-In the second embodiment, the tapered portions 43a having the same taper ratio are provided at both ends of the mandrel member 43, but the taper ratio of the tapered portion 43a may be different between one end side and the other end side.

-The fiber reinforced composite material 10 may include both a bent portion 20 and a tapered portion 21. For example, in the mandrel assembly step, by assembling the mandrel members 40 and 43 so as to have the bent portion 42a and the tapered portion 43a, the fiber reinforced composite material 10 having both the bent portion 20 and the tapered portion 21 can be manufactured.

The inclination angle α1 of the first UD tape 30a is not limited to 30 to 50 °. The inclination angle α1 of the first UD tape 30a can be appropriately selected within the range in which the fiber-reinforced composite material 10 can be preferably used. The same applies to the inclination angle −α1 of the second UD tape 30b.

-In the cross section orthogonal to the axial direction of the fiber-reinforced composite material 10, the inner peripheral shape of the fiber-reinforced composite material 10 is formed in a circular shape, but it may be formed in a shape other than the circular shape. For example, the inner peripheral shape of the fiber-reinforced composite material 10 may be an elliptical shape, an oval shape, a quadrangular shape, or a polygonal shape other than the quadrangular shape. By using the mandrel members 40 and 43 having a cross-sectional shape other than a circular shape, the inner peripheral shape of the fiber reinforced composite material 10 can be changed.

-The number of the first UD tape 30a, the second UD tape 30b, the third UD tape, and the metal fibers to be braided can be changed as appropriate. Further, at least one of the third UD tape and the metal fiber may be omitted.

-In the mandrel assembly process, the joint that connects the mandrel members may be omitted. For example, the mandrel members may be configured to be engaged and connected to each other in a concavo-convex relationship.

-In the braiding molding step, the automatic feeding means is configured to move the mandrel 42, but the present invention is not limited to this mode. Instead of moving the mandrel 42, the braiding device 50 may be configured to automatically feed. Further, the automatic feeding means is omitted and may be configured to be manually moved.

-In the method for producing the fiber-reinforced composite material 10, the impregnation step may be omitted. For example, in the braiding molding step, if the resin constituting the UD tape 30 is sufficiently melted and the contacts between the UD tapes 30 are suitably fixed, the impregnation step can be omitted.

10 ... Fiber reinforced composite material, 20 ... Bent part, 21 ... Tapered part, P1 ... Outside of bent part, P2 ... Inside of bent part, P3 ... Tip side of tapered part, P4 ... Base end side of tapered part.

Claims (6)

A fiber-reinforced composite material formed by UD tape woven into a tubular shape at a predetermined inclination angle.
The fiber-reinforced composite material has a bent portion bent in the axial direction of the fiber-reinforced composite material.
A fiber-reinforced composite material characterized in that the inclination angles are equal on the outside and the inside of the bent portion on the outer surface of the fiber-reinforced composite material. The fiber-reinforced composite material according to claim 1, wherein the inclination angle is an angle within ± 6 ° in the range of 30 to 50 °. The fiber-reinforced composite material according to claim 1 or 2, wherein the resin impregnated in the UD tape is a thermoplastic resin. The UD tape is formed in a state of being woven into a tubular shape at a predetermined inclination angle, and includes at least one of a bent portion bent with respect to the axial direction and a tapered portion having an outer diameter increasing along the axial direction. It is a manufacturing method of fiber reinforced composite material.
A mandrel assembly process in which a plurality of mandrel members are connected to assemble a mandrel having at least one of a plurality of bent portions and a plurality of tapered portions.
A braiding molding step of performing braiding molding on the mandrel obtained in the mandrel assembly step using UD tape, and a braiding molding step.
A cutting step of cutting the molded product obtained in the braiding molding step, and a cutting step of cutting the molded body.
A method for producing a fiber-reinforced composite material, which comprises a decentering step of pulling out the mandrel from a cut molded body. A resin film is wound around the surface of the molded product obtained in the braiding molding step, a high shrinkage tape is wound around the surface of the resin film, and then heat treatment is performed to obtain the resin constituting the resin film. The method for producing a fiber-reinforced composite material according to claim 4, further comprising an impregnation step of impregnating the molded product. The method for producing a fiber-reinforced composite material according to claim 4 or 5, wherein in the braiding molding step, the mandrel is moved by an automatic feeding means so that the mandrel is always positioned at a position where braiding molding is performed.

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