JP2017218688A - Reinforcing base material for composite material part, composite material part, and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a reinforcing base material for a composite material part even having a complicated curved surface while suppressing manufacturing costs and improving moldability and a composite material part.SOLUTION: The method for producing a reinforcing base material 6 used for a composite material part made of a fiber reinforced composite member, in which an aimed shape is an outline of the composite material part and which comprises: forming continuous loops 3 with a first reinforcing fiber yarn 2; knitting a knitted layer having a curved surface imitating the aimed shape by combining the continuous loops 3; and passing a second reinforcing fiber yarn 4 through the continuous loops 3 and interweaving it into the knitted layer to form a reinforced part.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a reinforced base material for composite parts, composite parts, and methods for producing them.

  Fiber Reinforced Plastics (FRP) is a composite material in which fibers are used as a reinforcing material and thermoplastic resin or thermosetting resin is used as a matrix. Since fiber reinforced plastic is lightweight and has high strength, it is widely used as a structural member for aircraft, automobiles, ships, etc. (Patent Document 1).

JP 2011-516294 A (summary, paragraph [0003] and paragraph [0004])

  When manufacturing a structural member using fiber reinforced plastic, first, a paper pattern 11 is created in accordance with the shape of the molded product 10 (FIGS. 6A and 6B). Next, the sheet-like preform 12 is cut according to the pattern paper 11 (FIG. 6C). The cut preform 12 'is pressed against the mold 13 to create a three-dimensional shape (FIG. 6 (d)).

  For the preform 12, a unidirectional fiber reinforced composite or a woven material is used. The unidirectional fiber reinforcement is a composite material in which the fiber direction is aligned only in one direction. The woven material is a composite material including a fiber woven fabric formed by crossing fiber threads.

  Unidirectional fiber reinforcements and woven materials have the characteristics that they are not easily adapted to complex curved surfaces and have poor flexibility and moldability. For this reason, if the sheet of the unidirectional fiber reinforcing material and the woven material is pressed against the complicated curved surface as it is, the fiber orientation is deviated or wrinkles occur. Therefore, when a structural member having a complicated curved surface is manufactured, parts are created by dividing, or a part of fibers difficult to be molded is cut and molded (see FIG. 6C). .

  The operation of cutting the fibers is not preferable because the integrity of the preform 12 is impaired and the strength is reduced. In Patent Document 1, the strength of the composite structure is improved by reinforcing using a woven fiber preform, eliminating the need for end bonding and ensuring isotropic properties.

  When a unidirectional fiber reinforcement or woven material is used, the fibers are oriented in the required direction by the required amount to ensure the strength of the structural member. For this reason, if there is a decrease in strength due to division creation or fiber cutting, the number of times the unidirectional fiber reinforcement or woven material is laminated increases, leading to deterioration in manufacturing costs.

  The present invention has been made in view of such circumstances, and a method of manufacturing a composite material part capable of improving moldability while suppressing manufacturing cost even for a composite material part having a complicated curved surface. The purpose is to provide.

  In order to solve the above-described problems, the following means are employed in the reinforced base material for composite material parts, the composite material parts, and the manufacturing method thereof according to the present invention.

A first aspect of the present invention is a method for producing a reinforced base material used for a composite part made of a fiber reinforced composite material, wherein the contour of the composite part has a target shape, and the first reinforcing fiber yarn is used. A continuous loop is formed, a continuous layer is combined to form a knitted layer having a curved surface following the target shape, and a second reinforcing fiber yarn is knitted into the knitted layer through the continuous loop to reinforce the reinforced portion. The manufacturing method of the reinforced base material which forms is provided.
In the first aspect, a step of laminating the reinforcing base material on a mold and shaping may be provided.

  According to a second aspect of the present invention, there is provided a method for producing a composite part, comprising a step of impregnating a matrix into the reinforced substrate produced in the first aspect.

  According to a third aspect of the present invention, a knitted fabric layer having a curved surface following the target shape, the curved surface being knitted by combining continuous loops of the first reinforcing fiber yarn, and the second reinforcing fiber yarn are the above-mentioned There is provided a reinforced base material for a composite part, comprising a reinforced portion that is passed through a continuous loop and knitted into the knitted layer.

  According to a fourth aspect of the present invention, there is provided a knitted layer having a curved surface that follows the target shape, the curved surface being knitted by combining continuous loops of the first reinforcing fiber yarn, and the second reinforcing fiber yarn. Provided is a composite part including a reinforced base material including a reinforcing part that is passed through the continuous loop and knitted into the knitted layer, and a matrix.

  By knitting the knitted layer so as to have a curved surface that follows the contour of the composite material part, it is possible to suppress the fiber orientation shift and wrinkle of the reinforcing base material when it is pressed against the mold and shaped. Therefore, an operation for cutting the reinforcing base material for shaping is unnecessary, or the number of times can be greatly reduced. Since the knitted layer is composed of a combination of continuous loops, it has stretch performance. Thereby, it can be set as the knitted layer provided with the high softness | flexibility and a moldability.

  By knitting the second reinforcing fiber into the knitted layer, it is possible to realize a high-strength reinforcing substrate. As a result, the number of laminations of the reinforced base material can be reduced, so that the manufacturing cost can be suppressed.

  According to the present invention, by using a reinforced base material formed by a knitting technique, even a composite material part having a complicated curved surface can be manufactured by improving the formability while suppressing the manufacturing cost. it can.

It is a figure explaining the composition of the knitting layer concerning this embodiment. It is a figure which illustrates the state when the knitted layer of FIG. 1 is pulled in the width direction. It is a figure which shows the example of orientation of a 2nd reinforcing fiber yarn. It is a figure which shows the example of orientation of a 2nd reinforcing fiber yarn. It is a figure which shows the lamination example of a reinforced base material. It is a figure explaining the conventional method which manufactures a structural member using fiber reinforced plastics.

  EMBODIMENT OF THE INVENTION Below, one Embodiment of the reinforcement base material for composite material parts which concerns on this invention, composite material components, and those manufacturing methods is described with reference to drawings.

  The composite part is made of a fiber reinforced composite material. The fiber reinforced composite material includes a matrix and a reinforced substrate. The composite material component may have a configuration in which a plurality of reinforcing substrates are laminated.

  The matrix is a thermosetting resin, a thermoplastic resin, or the like. Examples of the thermosetting resin include unsaturated polyester and epoxy resin. The thermoplastic resin is polyether ether ketone (PEEK), polyether ketone ketone (PEKK), polyphenylene sulfide (PPS), or the like.

  The reinforced substrate includes a knitted layer and a reinforced portion. The reinforced substrate is formed by a knitting technique.

  FIG. 1 is a diagram illustrating the configuration of the knitted layer. The knitted layer 1 is a layer knitted by combining continuous loops 3 of the first reinforcing fiber yarns 2. The loop 3 may be bound in either the vertical direction (length direction L) or the horizontal direction (width direction W). FIG. 1 illustrates the knitted material layer 1 when the loop 3 is bound in the vertical direction (weft knitting).

  The knitted layer 1 has a stretching performance that stretches in at least two directions of the length direction L and the width direction W. Thereby, flexibility is generated in the length direction L and the width direction W. FIG. 2 illustrates a state when the knitted layer 1 of FIG. 1 is pulled in the width direction W. When the weft knitted layer 1 is pulled in the width direction W, the shape of the loop 3 is deformed and extends in the width direction W. The loop 3 can be deformed not only in the width direction W but also in other directions.

  The knitted layer 1 has a single layer configuration. The knitted layer 1 is knitted to have a curved surface that follows the target shape. The target shape is the contour of the composite material part. The curved surface that follows the target shape may be any shape that is close to the contour of the composite material part when it is designed, and does not necessarily need to completely match the contour of the composite material part. “Near” means a difference that is within the range of the stretch performance of the knitted layer 1.

  The first reinforcing fiber yarn 2 is made of a material that is flexible enough to knit the knitted layer 1 and can be bonded to a matrix material. The material of the first reinforcing fiber yarn 2 is resin fiber, carbon fiber, glass fiber or the like. Resin fibers include polyamide fibers. The polyamide-based fiber is an aliphatic polyamide or aromatic polyamide fiber. The aliphatic polyamide is, for example, nylon (registered trademark). The aromatic polyamide is, for example, aramid.

  The first reinforcing fiber yarn 2 has a thickness (diameter) that can withstand the knitting of the knitted layer 1.

  The reinforcing portion is formed by knitting the second reinforcing fiber yarn into the knitted layer 1 through the loop 3. A plurality of second reinforcing fiber yarns are knitted in the knitted layer 1. The plurality of second reinforcing fiber yarns knitted are oriented in one direction or two directions in the knitted layer 1. The plurality of second reinforcing fiber yarns knitted may be oriented in a plurality of directions in the knitted layer 1. FIG. 3 and FIG. 4 illustrate the orientation of the second reinforcing fiber yarn. FIG. 3 is a diagram in which the second reinforcing fiber yarns 4 are oriented in the width direction W of the knitted knitted fabric layer 1. FIG. 4 is a diagram in which the second reinforcing fiber yarns 4 are oriented in the length direction L of the knitted knitted fabric layer 1. As shown in FIGS. 3 and 4, the knitting cycle of the second reinforcing fiber yarn 4 may be the same or different in the knitted layer. Further, the second reinforcing fiber yarn 4 may be oriented in an oblique direction in addition to the length direction L and the width direction W.

  The material of the second reinforcing fiber yarn 4 is carbon fiber, glass fiber, resin fiber, or the like. The second reinforcing fiber yarn 4 has a thickness (diameter) enough to be knitted into the loop 3 of the knitted layer 1. When the second reinforcing fiber yarn 4 is a carbon fiber, the fiber bundle preferably has a thickness of 12000 or more and 30000 or less, but this is not restrictive.

Next, the manufacturing method of a reinforcement base material and composite material components is demonstrated.
(Formation of reinforced substrate)
A continuous loop 3 is formed with the first reinforcing fiber yarns 2 and the knitted layer 1 is knitted. The knitted layer 1 can be knitted by weft knitting or warp knitting. The weft knitting is a flat knitting, rubber knitting, pearl knitting, lace knitting or the like. The warp knitting includes single / Denby and single / Bandike.

  When the knitted layer 1 is knitted, a curved surface that follows the target shape is applied to the knitted layer 1. When the knitted layer 1 is knitted, the knitting method may be appropriately changed according to the shape of the curved surface. For example, a three-dimensional structure that is partially stereoscopic can be provided by increasing or decreasing the stitches. For example, it is possible to give a curved surface by partially changing the length or width by narrowing the width of the whole structure by a method such as transfer or changing the knitting method to a different style. The target shape is the contour of the composite part to be manufactured. The curved surface does not need to completely match the target shape, but is preferably a shape close to the target shape.

  When the knitted layer 1 is knitted, the second reinforcing fiber yarns 4 are knitted into the knitted layer 1 in parallel to form the reinforcing base materials 5 and 6. For example, the knitted layer 1 can be knitted by inlay knitting. Inlay knitting is a knitting method in which a yarn is inlayed (inserted) into a base knitted fabric, and is realized by passing the yarn through a loop of the knitted fabric. The second reinforcing fiber yarn 4 may be knitted in parallel with the knitted layer 1, or may be knitted after forming a part or all of the knitted layer 1.

  When weaving into the knitted layer 1, the second reinforcing fiber yarns 4 are arranged in one direction or two directions. For example, the second reinforcing fiber yarns 4 are arranged in the length direction L as shown in FIG. For example, the second reinforcing fiber yarns 4 are arranged in the width direction W as shown in FIG. For example, the direction of some of the second reinforcing fiber yarns 4 may be aligned in the length direction L, and the direction of the remaining second reinforcing fiber yarns 4 may be aligned in the width direction W.

(Molding of reinforced substrate)
A reinforced substrate 5 having a curved surface following the target shape is laminated on a mold. The contour of the mold is substantially the same as the contour of the composite part. Therefore, when the reinforced substrate 5 is laminated on the mold, the position is adjusted so that the curved surface is aligned with the corresponding part.

  When the alignment is completed, the reinforcing substrate 5 is pressed against the mold and shaped. Since the reinforced base material 5 already has a curved surface that follows the target shape, the reinforced base material 5 can be directly pressed against the mold without being cut or the like. Even if the deformation amount of the reinforcing substrate 5 during shaping is small and there is a curved surface portion that does not match the contour of the mold, the stretch performance of the knitted layer 1 can cope with it. For example, when the curved surface portion is smaller than the contour of the mold, the knitted layer 1 can be stretched to make the reinforced substrate 5 conform to the contour of the mold. Thereby, even if it is a composite material part which has a complicated curved surface, a moldability can be improved.

  The reinforced substrate 5 is laminated in a plurality of layers on the mold. Shaping is performed each time the stacking is performed, or shaping is performed after stacking a plurality of layers. FIG. 5 shows an example of lamination. FIG. 5A shows a molded product shape 8. FIG. 5B shows reinforced substrates 7A, 7B. 7C. The first reinforcing substrate 7A, the second reinforcing substrate 7B, and the third reinforcing substrate 7C have different orientations of the second reinforcing fiber yarns 4, respectively. In the first reinforcing base 7A, the second reinforcing fiber yarn 4 is oriented at 0 °. In the second reinforcing base material 7B, the second reinforcing fiber yarns 4 are oriented at 90 °. In the third reinforcing substrate 7C, the second reinforcing fiber yarn is oriented at + 45 °. For example, the first reinforcing base material 7A is laminated on a mold and then shaped, the second reinforcing base material 7B is laminated on the shaped first reinforcing base material 7A, and then the second reinforcing base material 7B is shaped. After the third reinforced substrate 7C is laminated on the shaped second reinforced substrate 7B, the third reinforced substrate 7C is shaped.

  By stacking the first reinforced base material 7A, the second reinforced base material 7B, and the third reinforced base material 7C having different orientations, the strength of the composite material component can be improved with respect to loads from a plurality of directions. By intensively orienting the second reinforcing fiber yarn 4 in a predetermined direction, it is possible to have a necessary strength in a particularly necessary direction.

(Matrix impregnation)
After molding, the matrix is impregnated into the reinforced base material (in FIG. 5, the first reinforced base material 7A, the second reinforced base material 7B, and the third reinforced base material 7C are deposited). For example, the mold and the reinforced substrate can be covered with a bag, and the reinforced substrate can be impregnated with the matrix in a state where the inside of the bag is decompressed. For example, the reinforcing base material can be fitted into a molding die composed of an upper die and a lower die, and the inside of the molding die can be decompressed to be impregnated with the matrix.

  The thicknesses of the first reinforced base material 7A, the second reinforced base material 7B, and the third reinforced base material 7C reinforced base material impregnated with the matrix are each about 0.1 mm to 0.5 mm, for example. The thickness is, for example, about 0.5 mm to 10 mm.

  After impregnation, the matrix is cured. For example, when an epoxy resin is used as the matrix, the reinforced base material impregnated with the matrix is heated to a curing temperature (180 ° C. or higher) to be cured. Thereby, a composite material part can be obtained.

  In the above embodiment, the matrix is impregnated after the reinforced base material is laminated on the mold, but the present invention is not limited to this, and after forming the prepreg in which the matrix is impregnated into the reinforced base material, It may be laminated and shaped.

DESCRIPTION OF SYMBOLS 1 Knitted layer 2 1st reinforcement fiber yarn 3 Loop 4 2nd reinforcement fiber yarn 5, 6 Reinforcement substrate 7A 1st reinforcement substrate 7B 2nd reinforcement substrate 7C 3rd reinforcement substrate 8 Shape of molded article

Claims (5)

A method for producing a reinforced base material used for a composite part made of fiber reinforced composite material,
The contour of the composite part is a target shape,
A continuous loop is formed with the first reinforcing fiber yarn, and the continuous loop is combined to knit a knitted layer having a curved surface following the target shape,
A method for producing a reinforced base material, wherein a second reinforcing fiber yarn is knitted into the knitted layer through the continuous loop to form a reinforced portion.   The manufacturing method of the reinforced base material of Claim 1 provided with the process of laminating | stacking the said reinforced base material on a type | mold and shaping.   A method for producing a composite part, comprising a step of impregnating a matrix into a reinforced substrate produced by the method according to claim 1. A knitted layer having a curved surface that follows the target shape, and the curved surface is knitted by combining continuous loops of the first reinforcing fiber yarns;
A reinforcing portion in which a second reinforcing fiber yarn is passed through the continuous loop and knitted into the knitted layer;
Reinforced substrate for composite parts with A knitted fabric layer having a curved surface following the target shape, the curved surface being knitted by combining continuous loops of the first reinforcing fiber yarns, and the second reinforcing fiber yarns being passed through the continuous loops to A reinforced base material comprising a reinforced portion knitted into a knitted layer,
Matrix,
Including composite parts.

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