WO2018173322A1

WO2018173322A1 - Fiber-reinforced composite

Info

Publication number: WO2018173322A1
Application number: PCT/JP2017/032309
Authority: WO
Inventors: 洋一郎福永; 真章中村
Original assignee: 積水化成品工業株式会社
Priority date: 2017-03-24
Filing date: 2017-09-07
Publication date: 2018-09-27
Also published as: JP2018161775A; TWI661938B; TW201834842A; JP6731875B2

Abstract

Provided is a fiber-reinforced composite whereby, despite a fiber-reinforced resin being formed adjacent to an end part of a foamed resin layer therein, stress concentration at the boundary between the fiber-reinforced resin and the foamed resin layer can be reduced. The present invention is provided with a first fiber-reinforced resin layer 11, a second fiber-reinforced resin layer 12, a first composite part 10 having a foamed resin layer 13 formed between the first and second fiber-reinforced resin layers 11, 12, and a second composite part 20 comprising a fiber-reinforced resin and being formed adjacent to an end part 13a of the foamed resin layer 13, a portion of the foamed resin layer 13 that is adjacent to the second composite part 20 being configured as a high-density layer 13b having a high density relative to the other portion of the foamed resin layer 13.

Description

Fiber reinforced composite

The present invention relates to a fiber reinforced composite comprising a fiber reinforced resin and a foamed resin.

A fiber reinforced resin (FRP) in which a resin (plastic) is reinforced by reinforcing fibers such as carbon fiber and glass fiber is known. In recent years, FRP is lightweight and has excellent rigidity, and thus has become an indispensable component in various fields such as aircraft, automobiles, ships, and buildings.

Vehicles such as airplanes, automobiles, and ships are required to improve fuel efficiency in order to reduce the load on the global environment, and therefore, further weight reduction is required for FRP. In view of such a point, for example, a fiber reinforced resin including a first fiber reinforced resin layer, a second fiber reinforced resin layer, and a foamed resin layer formed between the first and second fiber reinforced resin layers. A complex has been proposed (see, for example, Patent Document 1). According to this technique, since the fiber reinforced composite is provided with the foamed resin layer that is lighter than the fiber reinforced resin (FRP), further weight reduction can be achieved.

JP 2016-49766 Gazette

Incidentally, the end face of the foamed resin layer is exposed as it is at the end face of the fiber-reinforced composite of Patent Document 1. Here, for example, when a fiber reinforced resin layer is newly arranged in parallel to further strengthen the end including the end face of the fiber reinforced composite, there is a difference in strength between the fiber reinforced resin layer and the foamed resin layer. As a result, it is assumed that stress concentrates on this boundary portion.

The present invention has been made in view of the above problems, and the object of the present invention is to reduce stress concentration at these boundaries even if a fiber reinforced resin is formed adjacent to the end of the foamed resin layer. It is to provide a fiber reinforced composite that can be used.

In view of the above problems, a fiber reinforced composite according to the present invention is a foamed resin formed between a first fiber reinforced resin layer, a second fiber reinforced resin layer, and the first and second fiber reinforced resin layers. A first composite part having a layer, and a second composite part formed adjacent to an end of the foamed resin layer and made of a fiber reinforced resin. Of the foamed resin layer, the second composite part is provided. A portion adjacent to the composite portion is a high-density layer having a higher density than other portions of the foamed resin layer.

According to the present invention, since the foamed resin layer is formed between the first and second fiber reinforced resin layers in the first composite part, the fiber reinforced composite can be further reduced in weight and fiber reinforced. The impact absorbability of the composite can be increased.

Furthermore, since the portion adjacent to the second composite portion of the foamed resin layer is a high-density layer having a higher density than other portions of the foamed resin layer, the density of the other portions of the foamed resin layer is reduced. In comparison, the density of the high-density layer is close to the density of the fiber reinforced resin of the second composite part. As a result, even if the fiber reinforced resin of the second composite portion is integrally formed adjacent to the end portion of the foamed resin layer, the difference in strength between them becomes small, so that stress concentration at these boundaries can be reduced. it can.

In a more preferred embodiment, the layer thickness of the high-density layer is thinner than the layer thickness of other portions of the foamed resin layer. According to this aspect, since the layer thickness of the high-density layer is thinner than the layer thickness of the other part of the foamed resin layer, the part (edge) where the high-density layer of the foamed resin layer contacts the second composite part Part) can be made smaller. For this reason, the interface between the high-density layer and the second composite portion can be reduced, and peeling of these can be suppressed.

As a more preferred embodiment, the layer thickness of the high-density layer is thinner as it approaches the second composite part. According to this aspect, since the layer thickness of the high-density layer becomes thinner as it approaches the second composite part, it is difficult to form a step or the like in the high-density layer, and stress concentration in the high-density layer can be reduced. it can.

As a more preferable aspect, the density of the high-density layer increases as the density approaches the second composite part. According to this aspect, since the density of the high-density layer becomes higher as it approaches the second composite part, the strength of the high-density layer approaches the strength of the second composite part as it approaches the second composite part. As a result, not only can the stress concentration caused by the strength difference between the foamed resin layer and the second composite part be reduced, but also the strength difference at the boundary between the high-density layer and the other foamed resin layer. It is possible to avoid stress concentration.

As a more preferable aspect, the second composite portion includes a first continuous layer in which at least a part of the first fiber reinforced resin layer is continuous, and a second continuous in which at least a part of the second fiber reinforced resin layer is continuous. Including layers. According to this aspect, since the second composite part has the first and second continuous layers continuous to the first and second fiber reinforced resin layers, respectively, the second composite part is provided between the first composite part and the second composite part. Strength can be increased.

As a further preferred aspect having the first and second continuous layers, a third fiber reinforced resin layer is further laminated on the second composite portion between the first continuous layer and the second continuous layer. ing. According to this invention, since the 3rd fiber reinforced resin layer is formed between the 1st continuous layer and the 2nd continuous layer, the intensity | strength of a 2nd composite part can be raised more. As a result, machining such as drilling a through hole in the second composite portion can be easily performed.

As another preferable aspect having the first and second continuous layers, the second composite part has a stacked structure in which the first continuous layer and the second continuous layer are bonded and stacked. According to this aspect, since the second composite part has a laminated structure in which the first and second continuous layers are joined and laminated, the entire second composite part is made a continuous part to the first composite part. Can do. Thereby, the intensity | strength between a 1st composite part and a 2nd composite part can be raised.

As a further preferred aspect, the second composite part is formed at the end of the fiber-reinforced composite. According to this aspect, since the second composite part is formed at the end of the fiber reinforced composite, the strength of the end of the fiber reinforced composite is increased, and the foamed resin layer is formed at the other part. Therefore, the weight of the fiber reinforced composite can be reduced and the shock absorption can be improved.

As yet another preferred embodiment, the second composite part is formed on the periphery of the fiber reinforced composite so as to surround the first composite part. According to this aspect, since the second composite part is formed so as to surround the first composite part, the overall strength of the fiber-reinforced composite can be increased. Moreover, since the foamed resin layer is formed in parts other than a peripheral part, the weight reduction of a fiber reinforced composite body can be achieved and shock absorption can be improved.

According to the fiber reinforced composite according to the present invention, even if the fiber reinforced resin is formed adjacent to the end of the foamed resin layer, the stress concentration at these boundaries can be reduced.

It is a typical perspective view for demonstrating the structure of the fiber reinforced composite_body | complex which concerns on 1st Embodiment of this invention. FIG. 2 is a cross-sectional view taken along line AA of the fiber reinforced composite shown in FIG. (A) is a sectional view taken along line BB of the fiber reinforced composite shown in FIG. 1, and (b) is a sectional view taken along line CC of the fiber reinforced composite shown in FIG. is there. It is a figure for demonstrating the manufacturing method of the fiber reinforced composite shown in FIG. (A)-(c) is principal part sectional drawing which showed the modification of the fiber reinforced composite_body | complex shown in FIG. It is a typical perspective view for demonstrating the structure of the fiber reinforced composite_body | complex which concerns on 2nd Embodiment of this invention. FIG. 7 is a cross-sectional view taken along line DD of the fiber reinforced composite shown in FIG. 6. It is a figure for demonstrating the manufacturing method of the fiber reinforced composite shown in FIG. It is the typical perspective view which showed the modification of the fiber reinforced composite_body | complex shown in FIG. (A)-(c) is principal part sectional drawing which showed the modification of the fiber reinforced composite_body | complex shown in FIG. (A) is typical sectional drawing for demonstrating the principal part of the fiber reinforced composite which concerns on 3rd Embodiment, (b) is the principal part of the fiber reinforced composite which concerns on the reference example of (a). It is a typical sectional view for explaining. It is a cross-sectional photograph of the fiber reinforced composite which concerns on an Example.

The fiber-reinforced composites according to the first and second embodiments according to the present invention will be described with reference to FIGS.

[First Embodiment]
1. About Fiber Reinforced Composite 1 As shown in FIG. 1, the fiber reinforced composite 1 according to the first embodiment has a flat plate shape and includes a first composite part 10 and a second composite part 20. The second composite part 20 is formed at both ends of the fiber reinforced composite 1, and the first composite part 10 is formed integrally with each second composite part 20 between them. In the present embodiment, the first and second

composite parts

10 and 20 have substantially the same thickness. In the present embodiment, the fiber reinforced composite 1 has a flat plate shape, but may be a curved shape or a twisted shape, and the shape is not particularly limited. In the present embodiment, the first and second

composite parts

10 and 20 have substantially the same thickness. For example, there is no stress concentration between the first composite part 10 and the second composite part 20. For example, these thicknesses may be different.

As shown in FIG. 2 and FIG. 3A, the first composite unit 10 includes a first fiber reinforced resin layer 11, a second fiber reinforced resin layer 12, and first and second fiber reinforced resin layers 11, 12. And a foamed resin layer 13 formed therebetween. The second composite portion 20 is a portion made of a fiber reinforced resin, adjacent to the end portion 13a of the foamed resin layer 13, and made of a fiber reinforced resin. In the present embodiment, a plurality of fiber reinforced resin layers are laminated. It is the laminated structure made.

As described above, the first composite portion 10 is a foamed resin formed between the first fiber reinforced resin layer 11, the second fiber reinforced resin layer 12, and the first and second fiber reinforced resin layers 11 and 12. Layer 13. The first and second fiber reinforced resin layers 11 and 12 include

outer layers

11a and 12a corresponding to the outer skin of the fiber reinforced composite 1, and

inner layers

11b and 12b corresponding to the inner sides thereof, , All are made of fiber reinforced resin (FRP).

2 and 3B, the second composite portion 20 is formed adjacent to the end portion 13a of the foamed resin layer 13 and is made of a fiber reinforced resin. The second composite portion 20 includes a first continuous layer 21 continuous with the outer layer 11 a that is at least a part of the first fiber reinforced resin layer 11, and an outer layer 12 a that is at least a part of the second fiber reinforced resin layer 12. A continuous second continuous layer 22. Thereby, since the 2nd composite part 20 has the 1st and 2nd

continuous layers

21 and 22 which followed the

outer layers

11a and 12a of the 1st and 2nd fiber reinforced resin layers 11 and 12, respectively, the 1st composite The strength between the part 10 and the second composite part 20 can be increased.

In particular, the first continuous layer 21 of the second composite portion 20 is preferably a layer in which a base material (for example, a woven base material) constituting the reinforcing fibers of the first fiber reinforced resin layer 11 is continuous. Similarly, it is preferable that the 2nd continuous layer 22 of the 2nd composite part 20 is a layer with which the base material (for example, textile base material) which comprises the reinforced fiber of the 2nd fiber reinforced resin layer 12 was continuous. Thereby, the intensity | strength between the 1st composite part 10 and the 2nd composite part 20 can be raised further.

In the second composite part 20, a third fiber reinforced resin layer 23 is further laminated between the first continuous layer 21 and the second continuous layer 22. The third fiber reinforced resin layer is a layer in which a plurality of fiber reinforced resin layers are laminated. Thus, since the 3rd fiber reinforced resin layer 23 is formed between the 1st continuous layer 21 and the 2nd continuous layer 22, the intensity | strength of the 2nd composite part 20 can be raised further. Accordingly, machining such as drilling a through hole in the second composite portion 20 can be easily performed.

Here, the fiber reinforced resin of the first composite part 10 and the second composite part 20 is composed of a reinforced fiber and a synthetic resin (matrix resin) that bonds the reinforced fibers together. Reinforcing fibers include glass fibers, carbon fibers, silicon carbide fibers, alumina fibers, tyrano fibers, basalt fibers, ceramic fibers and other inorganic fibers; stainless steel fibers and steel fibers; aramid fibers, polyethylene fibers, polyparaphenylene Organic fibers such as benzoxador (PBO) fibers; or boron fibers. Reinforcing fibers may be used alone or in combination of two or more. Among these, carbon fiber, glass fiber, or aramid fiber is preferable, and carbon fiber is more preferable. These reinforcing fibers have excellent mechanical strength despite being lightweight.

The reinforcing fiber may be either a long fiber or a short fiber, but is preferably used as a reinforcing fiber substrate processed into a desired shape. Examples of the reinforcing fiber base material include woven fabrics, knitted fabrics, nonwoven fabrics, or face materials formed by binding (stitching) fiber bundles (strands) obtained by aligning reinforcing fibers in one direction with yarns. . Examples of the weaving method include plain weave, twill weave and satin weave. The fiber reinforced base material may be used without laminating only one fiber reinforced base material, or a plurality of fiber reinforced base materials may be laminated and used as a laminated fiber reinforced base material.

Synthetic resin is a resin that is impregnated into reinforcing fibers and bonds the reinforcing fibers together. The reinforcing fibers can be bonded and integrated by the impregnated synthetic resin. The synthetic resin impregnated into the reinforcing fibers may be either a thermosetting resin or a thermoplastic resin, but more preferably a thermosetting resin. The thermosetting resin is not particularly limited. For example, epoxy resin, unsaturated polyester resin, phenol resin, melamine resin, polyurethane resin, silicon resin, maleimide resin, vinyl ester resin, cyanide. Examples thereof include acid ester resins, or resins obtained by prepolymerizing maleimide resins and cyanate ester resins. A thermosetting resin may be used independently or 2 or more types may be used together. Of these, epoxy resins or vinyl ester resins are preferable. According to these synthetic resins, a fiber reinforced resin excellent in elasticity can be formed, and the impact resistance of the resulting fiber reinforced composite 1 can be improved. Further, the thermosetting resin may contain additives such as a curing agent and a curing accelerator. The fiber reinforced resin may be molded by a sheet molding compound (SMC).

The content of the thermosetting resin in the fiber reinforced resin is preferably 20 to 70% by weight, more preferably 30 to 60% by weight. If the content of the thermosetting resin is too small, the binding property between the reinforcing fibers and the adhesion between the first and second fiber reinforced resin layers 11 and 12 and the foamed resin layer 13 become insufficient, and the first and first There is a possibility that the mechanical strength of the two fiber reinforced resin layers 11 and 12 and the impact resistance of the fiber reinforced composite 1 cannot be sufficiently improved. Moreover, when there is too much content of a thermosetting resin, the mechanical strength of the 1st and 2nd fiber reinforced resin layers 11 and 12 will fall, and the impact resistance of the fiber reinforced composite 1 will fully be improved. You may not be able to.

The foamed resin layer 13 constituting the fiber reinforced composite 1 contains a foamed synthetic resin. The synthetic resin preferably has a polar group such as a cyano group, a hydroxy group (hydroxyl group), a carbonyl group, an amino group, an epoxy group, a halogen atom, an oxo group, or a phenyl group. By using a synthetic resin having a polar group, the foamed resin layer 13 including this and the first and second fiber reinforced resin layers 11 and 12 can be firmly integrated. Thereby, when an impact is applied to the fiber reinforced composite 1, the peeling between the foamed resin layer 13 and the first and second fiber reinforced resin layers 11 and 12 is reduced, so that the impact resistance of the fiber reinforced composite 1 is increased. This can be further improved.

Specific examples of the synthetic resin used for the foamed resin layer 13 include polycarbonate resins, acrylic resins, thermoplastic polyester resins, polymethacrylimide resins, polystyrene resins, polyamide resins, and polypropylene resins. Can be mentioned. In addition, a synthetic resin may be used independently or 2 or more types may be used together. Especially, since the foamed resin layer 13 and the 1st and 2nd fiber reinforced resin layers 11 and 12 can be integrated more firmly, a thermoplastic polyester-type resin or a polyamide-type resin is preferable, and a thermoplastic polyester type | system | group is preferable. A resin is more preferable.

In the present embodiment, in the foamed resin layer 13, a portion (end portion 13 a) adjacent to the second composite portion 20 is a high-density layer 13 b having a higher density than other portions of the foamed resin layer 13. . More specifically, the density of the high-density layer 13 b increases as the second composite portion 20 is approached. The density of the high-density layer 13b is preferably in the range of 0.2 to 0.9 g / cm ³ , and the other portions of the foamed resin layer 13 are assumed to be 0.00 on the premise that the density of the high-density layer 13b is high. It is preferably in the range of 05 to 0.3 g / cm ³ . The density of the high-density layer in the present specification refers to a value measured according to JIS K7222: 2005 “Foamed plastics and rubbers—Measurement of apparent density”.

Thus, since the high density layer 13b is formed in the foamed resin layer 13, the density of the high density layer 13b is higher than that of the other parts of the foamed resin layer 13. Close to the density of fiber reinforced resin. Thereby, even if the fiber reinforced resin of the second composite portion 20 is integrally formed adjacent to the end portion of the foamed resin layer 13, the strength difference between them becomes small, so that the stress concentration at these boundaries is reduced. be able to.

In addition to this, in the present embodiment, the density of the high-density layer 13b increases as it approaches the second composite part 20, and therefore the strength of the high-density layer 13b increases as the second composite part 20 approaches. The strength of the composite part 20 is approached. Thus, not only can the stress concentration caused by the strength difference between the foamed resin layer 13 and the second composite portion 20 be reduced, but also the strength difference in the high-density layer 13b. Stress concentration can also be avoided.

Further, in the present embodiment, the layer thickness of the high-density layer 13b is thinner than the layer thickness of the other part of the foamed resin layer 13. More specifically, the layer thickness of the high-density layer 13b becomes thinner as the second composite portion 20 is approached. Further, a resin reservoir 15 is formed in the first fiber reinforced resin layer adjacent to the high density layer 13b. The resin reservoir 15 is formed of either the above-described fiber reinforced resin or synthetic resin, and can be selected depending on the material of the insert material 15 ′ described later.

In the present embodiment, since the layer thickness of the high-density layer 13b is thinner than the layer thickness of other portions of the foamed resin layer 13, the high-density layer 13b of the foamed resin layer 13 contacts the second composite portion 20. The part (end part) to perform can be made small. For this reason, the interface between the high-density layer 13b and the second composite portion 20 can be reduced, and peeling of these can be suppressed.

In addition, since the layer thickness of the high-density layer 13b becomes thinner as it approaches the second composite portion 20, it is difficult to form a step or the like in the high-density layer 13b, and stress concentration in the foamed resin layer 13 is reduced. can do. Furthermore, by providing the resin reservoir 15, it is possible to avoid the formation of voids in the fiber reinforced composite 1.

Here, the width (length in the direction perpendicular to the thickness direction of the layer) b of the high-density layer 13b is more preferably 5 to 20 mm, and the other layers except for the high-density layer 13b The thickness (that is, the maximum thickness of the high-density layer 13b) t is more preferably 1 to 20 mm, and t / b is more preferably in the range of 5 to 20 mm. By satisfying this range, even if the fiber reinforced resin is integrally formed adjacent to the end portion 13a of the foamed resin layer 13, the stress concentration at these boundaries can be reduced.

Further, t / T, which is a ratio of the thickness t of the other portion excluding the high density layer 13b and the thickness T of each layer of the first and second fiber reinforced resins, is in the range of 0.5 to 0.225. More preferably. By satisfying this range, it is possible to further ensure the impact absorbability of the fiber reinforced composite 1 while ensuring the rigidity of the fiber reinforced composite 1.

2. About the manufacturing method of the fiber reinforced composite 1 FIG. 4: is a figure for demonstrating the manufacturing method of the fiber reinforced composite 1 shown in FIG. As shown in FIG. 4, corresponding fiber reinforced resin sheets 11 b ′ and 12 b ′ corresponding to the

inner layers

11 b and 12 b of the fiber reinforced composite 1 are prepared, and a foamed resin sheet 13 ′ preliminarily foamed therebetween is prepared. A laminated body 10 ′ sandwiching the film is formed. Next, the stacked body 10 ′ is disposed between the upper mold 51 and the lower mold 52.

Next, a fiber reinforced resin block 23 ′ in which a plurality of fiber reinforced resin sheets are stacked is disposed at a position adjacent to the foamed resin sheet 13 ′ of the laminated body 10 ′. Next, the insert material 15 ′ is disposed between the laminate 10 ′ and the fiber reinforced resin block 23 ′. The insert material 15 ′ may be made of the same type of synthetic resin as the resin of the fiber reinforced resin sheet, or may be a fiber reinforced resin obtained by impregnating a reinforced fiber with a synthetic resin. Next, fiber reinforced resin sheets 11a 'and 12a' corresponding to the

outer layers

11a and 12a and the

continuous layers

21 and 22 are laminated so as to cover them.

And between the upper mold | type 51 and the lower mold | type 52, the laminated body 10 'covered with the fiber reinforced resin sheet 11a' and 12a ', the fiber reinforced resin block 23', and insert material 15 'is arrange | positioned, and the upper mold | type 51 is arranged. The lower mold 52 is heated while being pressurized. Moreover, on the assumption that the heating temperature at this time is equal to or higher than the temperature at which the foamed resin sheet 13 'is foamed, when the synthetic resin of the fiber reinforced resin sheet is a thermoplastic resin, the heating temperature is equal to or higher than the softening point temperature. is there. On the other hand, when the synthetic resin of the fiber reinforced resin sheet is a thermosetting resin, the temperature is equal to or higher than the curing point temperature.

By the mold clamping, the foamed resin sheet 13 ′ is foamed to a predetermined thickness, and the end portion 13 a ′ of the foamed resin sheet 13 ′ is pressed against the insert material 15 ′. Thereby, foaming of the end portion 13a ′ of the foamed resin sheet 13 ′ is suppressed, and the portion of the foamed resin layer 13 adjacent to the second composite portion 20 has a higher density than other portions of the foamed resin layer 13. Is formed as a high-density layer 13b. The density of the high-density layer 13b increases as the second composite portion 20 is approached.

Furthermore, since the insert material 15 ′ deforms the end portion 13 a ′ of the foamed resin sheet 13 ′ by pressing, the layer thickness of the high-density layer 13 b is made thinner than the layer thickness of other portions of the foamed resin layer 13. The layer thickness of the high-density layer 13b can be reduced as the second composite portion 20 is approached.

3. Other Modifications FIGS. 5 (a) to 5 (c) are main part sectional views showing a modification of the fiber reinforced composite 1 shown in FIG. For example, in FIG. 2, the layer thickness of the high-density layer 13 b is changed to the second composite portion 20 by tilting the interface on one side (the first fiber reinforced resin layer 11 side) of the high-density layer 13 b of the foamed resin layer 13. As it approached, it became thinner.

However, as shown in FIG. 5 (a), by inclining the interface of both the high-density layer 13b of the foamed resin layer 13 (the first fiber reinforced resin layer 11 side and the second fiber reinforced resin layer 12 side), The layer thickness of the high-density layer 13b may become thinner as the second composite unit 20 is approached. The high-density layer 13b having such a shape can be molded by disposing the insert material 15 'on both sides between the laminate 10' and the fiber reinforced resin block 23 '.

Furthermore, as shown in FIG. 5B, the thickness of the high-density layer 13b may be made substantially uniform by denting one side of the foamed resin layer 13, and as shown in FIG. By denting both sides of the foamed resin layer 13, the thickness of the high-density layer 13b may be made substantially uniform.

[Second Embodiment]
1. About Fiber Reinforced Composite 1A FIG. 6 is a schematic perspective view for explaining the structure of the fiber reinforced composite 1A according to the second embodiment of the present invention, and FIG. 7 shows the fiber reinforced composite shown in FIG. FIG. 2 is a cross-sectional view taken along the line DD of 1A. In addition, the same structure as 1st Embodiment attaches | subjects the same code | symbol, and abbreviate | omits detailed description.

In the present embodiment, the fiber-reinforced composite body 1A according to the second embodiment has a three-dimensional shape (plate shape). The bottom part 1a and the rising part 1b of the fiber reinforced composite 1A are formed by the first composite part 10, and the second composite part 20 is formed so as to surround the first composite part 10. That is, in the present embodiment, the ring-shaped second composite portion 20 is formed on the peripheral edge portion 1c of the fiber-reinforced composite body 1A. In the present embodiment, the fiber reinforced composite 1A has a plate shape, but may be, for example, a cup shape, a flat plate shape, a bottomed cylindrical shape, or a dome shape, and around the first composite portion 10. If the 2nd composite part 20 is formed so that it may surround, the shape in particular will not be limited.

Thus, since the 2nd composite part 20 is formed so that the circumference | surroundings of the 1st composite part 10 may be enclosed, by raising the intensity | strength of the peripheral part 1c of the fiber reinforced composite 1A, the fiber reinforced composite 1A whole is increased. Strength can be increased. Further, since the second composite part 20 is formed so as to surround the first composite part 10, it is possible to prevent moisture from entering the foamed resin layer 13. Furthermore, since the foamed resin layer 13 of the first composite part 10 is formed at a part other than the peripheral part 1c, the weight of the fiber-reinforced composite 1A can be reduced and the shock absorption can be enhanced.

Here, as shown in FIG. 7, the second composite part 20 has a laminated structure in which a first continuous layer 21 and a second continuous layer 22 are joined and laminated. For this reason, unlike the first embodiment, the entire second composite unit 20 can be a continuous part of the first composite unit 10. Thereby, the intensity | strength between the 1st composite part 10 and the 2nd composite part 20 can be raised. Further, in the present embodiment, as in the first embodiment, the foamed resin layer 13 has a high density layer in which the portion adjacent to the second composite portion 20 has a higher density than the other portions of the foamed resin layer 13. Since it is 13b, stress concentration between the first composite part 10 and the second composite part 20 can be avoided.

Note that the density of the high-density layer 13b increases as it approaches the second composite portion 20, and the layer thickness of the high-density layer 13b is thinner than the thickness of the other part of the foamed resin layer 13, and As it gets closer to the second composite part 20, it becomes thinner. Thereby, the effect similar to the effect demonstrated in 1st Embodiment can be anticipated.

2. About the manufacturing method of 1 A of fiber reinforced composites FIG. 8: is a figure for demonstrating the manufacturing method of 1 A of fiber reinforced composites shown in FIG. As shown in FIG. 8, corresponding fiber reinforced resin sheets 11 ′ and 12 ′ corresponding to the first and second fiber reinforced resin layers 11 and 12 of the fiber reinforced composite 1A are prepared, and pre-foamed between them. A laminated body 10 ′ sandwiching the foamed resin sheet 13 ′ is molded.

Then, the laminated body 10 ′ is disposed between the upper mold 51 A and the lower mold 52 A, and heated while pressurizing them with the upper mold 51 A and the lower mold 52 A. Moreover, the heating temperature at this time is the same as the temperature demonstrated in 1st Embodiment.

By the mold clamping, the foamed resin sheet 13 ′ is foamed to a predetermined thickness. However, since the end 13a ′ of the foamed resin sheet 13 ′ is pressed by the upper mold 51A, the foamed resin sheet 13 ′ is foamed as compared with other parts. It is suppressed. Thereby, in the foamed resin layer 13, the density of the part adjacent to the 2nd composite part 20 becomes high compared with the density of the other part of the foamed resin layer 13, and this part is shape | molded as the high-density layer 13b. The density of the high-density layer 13b increases as the second composite portion 20 is approached.

Furthermore, since the end portion of the foamed resin sheet 13 ′ is deformed by the shape of the upper mold 51A, the layer thickness of the high-density layer 13b can be made thinner than the layer thickness of the other part of the foamed resin layer 13, The layer thickness of the high-density layer 13b can be reduced as the second composite portion 20 is approached.

3. Other Modifications FIG. 9 is a schematic perspective view showing a modification of the fiber-reinforced composite 1A shown in FIG. As shown in FIG. 9, the fiber reinforced composite 1 A includes a bottom 1 a and a peripheral edge 1 c of the fiber reinforced composite 1 A formed by the second composite parts 20 A and 20 B, and a rising part 1 b formed by the first composite part 10. Is formed. An opening 1d is formed in the bottom 1a.

In this modification, a disk-shaped second composite portion 20A is formed so as to surround the bottom side of the first composite portion 10 of the rising portion 1b of the fiber reinforced composite 1A, and the rising of the fiber reinforced composite 1A. The ring-shaped second composite part 20B is formed so as to surround the opening side of the first composite part 10 of the part 1b. Thereby, even if the opening part 1d is formed in the bottom part 1a, the foamed resin layer of the 1st composite part 10 is not exposed.

FIGS. 10 (a) to 10 (c) are cross-sectional views of main parts showing a modification of the fiber reinforced composite 1A shown in FIG. For example, in FIG. 7, the layer thickness of the high-density layer 13b is set to the second composite portion 20 by inclining the interface on one side (the first fiber reinforced resin layer 11 side) of the high-density layer 13b of the foamed resin layer 13. As it approached, it became thinner.

However, as shown in FIG. 10A, by inclining the interface of both the high density layer 13b of the foamed resin layer 13 (the first fiber reinforced resin layer 11 side and the second fiber reinforced resin layer 12 side), The layer thickness of the high-density layer 13b may become thinner as the second composite unit 20 is approached.

Furthermore, as shown in FIG. 10B, the thickness of the high-density layer 13b may be made substantially uniform by denting one side of the foamed resin layer 13, and as shown in FIG. By denting both sides of the foamed resin layer 13, the thickness of the high-density layer 13b may be made substantially uniform.

[Third Embodiment]
Fig.11 (a) is typical sectional drawing for demonstrating the principal part of the fiber reinforced composite_body | complex 1B which concerns on 3rd Embodiment, FIG.11 (b) concerns on the reference example of Fig.11 (a). It is typical sectional drawing for demonstrating the principal part of the fiber reinforced composite_body | complex 1B. This embodiment is different from the first embodiment in that an end covering layer 12c and a continuous layer 12d are further provided. In addition, the same structure as 1st Embodiment attaches | subjects the same code | symbol, and abbreviate | omits detailed description.

In the present embodiment, an end covering layer 12c that covers the end surface of the first composite portion 10 is formed continuously with the inner layer 12b of the second fiber reinforced resin layer 12, and is continuously formed with the end covering layer 12c. The continuous layer 12d laminated | stacked as a part of 2 composite part 20 is further formed. In the case of the woven fabric base material of the reinforcing fiber of the inner layer 12b, the woven base material is formed continuously with the end covering layer 12c and the continuous layer 12d.

The end portion covering layer 12c is formed at a position separating the first and second

composite portions

10 and 20, and the reinforcing fibers of the end portion covering layer 12 are oriented along these adjacent end faces. According to this embodiment, since the end portion covering layer 12c and the continuous layer 12d are formed continuously to the inner layer 12b of the second fiber reinforced resin layer 12, the first composite portion 10 and the second composite portion 20 are formed. It is possible to increase the bonding strength.

In addition to this, the end cover layer 12c covers the end face of the first composite part 10, and the reinforcing fibers of the end cover layer 12c are oriented on the end face of the first composite part 10. It is possible to suppress the foamed resin layer 13 from being impregnated with the synthetic resin of the three-fiber reinforced resin layer 23. As a result, the synthetic resin of the third fiber reinforced resin layer 23 is impregnated in the foamed resin layer 13, thereby suppressing the formation of dents on the surface of the fiber reinforced composite 1 B.

In this embodiment, it is a premise that the high density layer 13b is formed on the foamed resin layer 13, but as shown in FIG. 11B, the high density layer 13b is not provided, and the end covering layer 12c is provided. May be formed. Even in this case, it is possible to suppress the formation of a dent on the surface of the fiber-reinforced composite 1B during manufacturing, and to increase the bonding strength between the first composite part 10 and the second composite part 20.

Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto.

The fiber reinforced composite shown in FIG. 1 was manufactured according to the manufacturing method described with reference to FIG. First, a fiber reinforced resin sheet (prepreg) in which an uncured epoxy resin is impregnated on a carbon fiber woven base material corresponding to the inner layer of the fiber reinforced composite is prepared, and a foamed resin pre-foamed between them. The laminated body which pinched | interposed the sheet | seat (polyester-type resin foam sheet) was shape | molded.

A fiber reinforced resin plate in which a plurality of fiber reinforced resin sheets similar to those described above are laminated is disposed at a position adjacent to the foamed resin sheet of this laminate. Next, an insert material made of fiber reinforced resin was disposed between the laminate and the fiber reinforced resin plate. Further, a fiber reinforced resin sheet for the skin was laminated so as to cover them.

Then, between the upper mold and the lower mold, a laminate, a fiber reinforced resin plate, and an insert material, which are covered with a fiber reinforced resin sheet for the skin, are arranged, and these are pressed with the upper mold and the lower mold. The heat treatment was carried out at 130 ° C. for 30 minutes and naturally cooled to 40 ° C. The cross section of the obtained fiber reinforced composite was observed. The result is shown in FIG. As shown in FIG. 12, a foamed resin layer is formed between the first and second fiber reinforced resin layers (FRP layers) of the first composite part, and the layer thickness decreases as the second composite part is approached. It was.

Furthermore, in the cross section shown in FIG. 12, the density of the foamed resin layer with the layer thickness becoming thinner and the density of the other part of the foamed resin layer were measured as approaching the second composite part. As a result, the density of the foamed resin layer whose layer thickness is thin becomes higher than the density of the other part of the foamed resin layer, and the thin foamed resin layer becomes higher as it approaches the second composite part. It was found that a high density layer was formed.

As mentioned above, although several embodiment of this invention was explained in full detail, this invention is not limited to the said embodiment, In the range which does not deviate from the mind of this invention described in the claim, it is various. Design changes can be made.

For example, the structure according to the first embodiment shown in FIGS. 2 and 5 may be applied to the structure according to the second embodiment shown in FIGS. 7 and 10, and the second embodiment shown in FIGS. Such a structure may be applied to the structure according to the first embodiment shown in FIGS.

1: fiber reinforced composite, 11: first fiber reinforced resin layer, 12: second fiber reinforced resin layer, 13: foamed resin layer, 13b: high density layer, 20: second composite part, 21: first continuous layer , 22: second continuous layer, 23: third fiber reinforced resin layer

Claims

A first composite part having a first fiber reinforced resin layer, a second fiber reinforced resin layer, and a foamed resin layer formed between the first and second fiber reinforced resin layers;
A second composite part formed adjacent to an end of the foamed resin layer and made of a fiber-reinforced resin,
Of the foamed resin layer, a portion adjacent to the second composite portion is a high-density layer having a higher density than other portions of the foamed resin layer.
2. The fiber-reinforced composite according to claim 1, wherein a layer thickness of the high-density layer is thinner than a layer thickness of other portions of the foamed resin layer.
The fiber-reinforced composite according to claim 2, wherein the layer thickness of the high-density layer becomes thinner as it approaches the second composite part.
The fiber-reinforced composite according to any one of claims 1 to 3, wherein the density of the high-density layer increases as the density approaches the second composite part.
The second composite part includes a first continuous layer in which at least a part of the first fiber reinforced resin layer is continuous, and a second continuous layer in which at least a part of the second fiber reinforced resin layer is continuous. The fiber-reinforced composite according to any one of claims 1 to 4, wherein
The fiber reinforced composite according to claim 5, wherein a third fiber reinforced resin layer is further laminated on the second composite part between the first continuous layer and the second continuous layer. body.
The fiber-reinforced composite according to claim 5, wherein the second composite part has a laminated structure in which the first continuous layer and the second continuous layer are joined and laminated.
The fiber reinforced composite according to any one of claims 1 to 7, wherein the second composite part is formed at an end of the fiber reinforced composite.
The second composite part is formed at a peripheral part of the fiber reinforced composite so as to surround the first composite part. Fiber reinforced composite.