JP6955872B2 - Fiber reinforced plastic molded product - Google Patents

Description

The present invention relates to a fiber reinforced resin molded product.

Conventionally, a fiber-reinforced resin molded product composed of FRP (Fiber Reinforced Plastics), which is a kind of composite material, is known (see, for example, Patent Document 1).

Patent Document 1 describes a method for manufacturing a curved honeycomb panel having an inner surface plate and an outer surface plate made of FRP bonded to both sides of a honeycomb core serving as a core material and having a predetermined curvature. In this manufacturing method, FRP plates are attached to both sides of the honeycomb core for the spacer by the manufacturing mold having a predetermined curvature in advance, and the amount of meat is increased by the amount of the inner surface plate from the manufactured curved honeycomb panel. The thin spacer panel is pressure molded. Then, first, the outer surface plate is pressure-molded by the mold, the spacer panel is laminated on the mold, and the inner surface plate is pressure-molded on the outer surface side thereof. Next, the honeycomb core, which is the core material, is sandwiched between the inner surface plate and the outer surface plate thus formed via an adhesive, and pressure molding is performed by the mold to obtain the curved honeycomb panel. Be done.

Japanese Patent No. 3204529

The fiber-reinforced resin molded product is generally composed of a core material formed in a plate shape and a fiber-reinforced resin layer formed on both sides of the core material. In such a fiber-reinforced resin molded product, when the core material has a portion (curved portion) having a larger curvature than other portions (general portion), the plate thickness of the core material is small in the curved portion having a large curvature. , The rigidity against external impact is generally weakened.

Therefore, an object of the present invention is to provide a fiber-reinforced resin molded product capable of improving the rigidity against an external impact.

The fiber-reinforced resin molded product according to the present invention is formed in a plate shape, and is formed on at least one of both sides of a core material having a general portion and a curved portion having a curvature larger than that of the general portion. It is provided with a first fiber reinforced resin layer. The fiber-reinforced resin molded product further includes a second fiber-reinforced resin layer formed between the curved portion of the core material and the first fiber-reinforced resin layer, and the second fiber contained in the second fiber-reinforced resin layer. The elongation rate is higher than the elongation rate of the first fiber contained in the first fiber reinforced resin layer.

According to the present invention, it is possible to provide a fiber reinforced resin molded product capable of improving the rigidity against an external impact.

It is a perspective view of the fiber reinforced resin molded article which concerns on embodiment of this invention. FIG. 1 is a cross-sectional view taken along the line AA of FIG. FIG. 1 is a cross-sectional view taken along the line BB of FIG. FIG. 5 is a cross-sectional view corresponding to the cross section taken along line BB of FIG. 1, showing a state in which an impact load is applied to the fiber-reinforced resin molded product according to the embodiment of the present invention. It is sectional drawing corresponding to the BB line cross section of FIG. 1 which shows the fiber-reinforced resin molded article which concerns on another Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

The fiber-reinforced resin molded product according to the embodiment of the present invention will be described with reference to FIGS. 1 to 4.

The fiber-reinforced resin molded product according to the embodiment of the present invention can be applied to vehicle components such as a hood (bonnet), a door panel, a bumper, a trunk lid, a rear gate, a fender panel, a side body panel, and a roof panel. can. Further, the fiber-reinforced resin molded product according to the embodiment of the present invention is not limited to vehicle components, and can be applied to various components.

The fiber-reinforced resin molded product 10 shown in FIG. 1 is a so-called hood outer, and is combined with a hood inner 11 (see FIG. 2) to form a vehicle hood. In FIG. 1, the arrow FR indicates the front of the vehicle, the arrow UPR indicates the upper side of the vehicle, and the arrow RH indicates the right side of the vehicle.

The fiber-reinforced resin molded product 10 constituting the hood outer has a shape that is smoothly curved so as to be convex upward toward the fiber-reinforced resin molded product 10 as a whole. Further, on the left and right side portions of the fiber reinforced resin molded product 10 (hood outer) in the vehicle width direction, bead portions 12 having a convex shape toward the upper side are formed along the front-rear direction of the vehicle. The shape of the bead portion 12 is defined by curved portions 16, 17, and 18, which will be described later, and the ridgeline portion (top) of the bead portion 12 mainly functions as a character line extending in the front-rear direction of the vehicle.

As shown in FIGS. 2 and 3, the fiber reinforced resin molded product 10 is a plate-shaped core material 13 and a first fiber reinforced resin formed on at least one of both sides of the core material 13. It is mainly composed of a layer 14. In the present embodiment, the first fiber reinforced resin layer 14 is formed on both sides of the core material 13.

The core material 13 has a general portion 15 and curved portions 16, 17, 18 having a larger curvature (smaller radius of curvature) than the general portion 15. That is, the general portion 15 indicates a portion having a smaller curvature (larger radius of curvature) than the curved portions 16, 17, 18 and the curved portions 16, 17, 18 have a larger curvature (having a larger radius of curvature) than the general portion 15. It shall indicate a (small) part. The plate thickness of the general portion 15 of the core material 13 is larger than the plate thickness of the curved portions 16, 17 and 18, and is set to, for example, about 5 mm. On the other hand, the plate thickness of the curved portions 16, 17, and 18 of the core material 13 is smaller than the plate thickness of the general portion 15, for example, about 2 mm. As such a core material 13, a porous body such as an aluminum honeycomb or a paper honeycomb, or a foam such as polyurethane foam can be used.

The first fiber reinforced resin layer 14 is composed of the first fiber and the first resin. As the first fiber reinforced resin layer 14, for example, carbon fiber reinforced resin (CFRP) can be used. That is, the first fiber is composed of, for example, carbon fiber. As the first fiber, a fabric material (woven fabric), a UD material (unique directional material), and a plurality of UD materials laminated can be used. On the other hand, as the first resin, various synthetic resins such as thermosetting resin and thermoplastic resin can be used. The first fiber reinforced resin layer 14 on the upper surface side (outer surface side of the hood) has, for example, a plate thickness of about 0.44 mm and is pseudo-isotropic such as [0 ° / 45 ° / −45 ° / 90 °]. It is conceivable to have a laminated structure. On the other hand, the first fiber reinforced resin layer 14 on the lower surface side (inner surface side of the hood) has, for example, a plate thickness of about 0.44 mm, and is simulated as [90 ° / −45 ° / 45 ° / 0 °]. It is conceivable to have an isotropic laminated structure.

As shown in FIG. 3, the fiber-reinforced resin molded product 10 includes a second fiber-reinforced resin layer 19 formed between the curved portions 16, 17, 18 of the core material 13 and the first fiber-reinforced resin layer 14. ing. The second fiber-reinforced resin layer 19 is formed on the upper and lower surfaces of the fiber-reinforced resin molded product 10 on the surface that becomes the compression side (the surface on which the compressive stress acts) when an impact load from the outside is applied. Is preferable. In the present embodiment, the second fiber reinforced resin layer 19 is formed only on the upper surface side (outer surface side of the hood) of the first fiber reinforced resin layers 14 and 14 on both the upper and lower sides of the fiber reinforced resin molded product 10.

The second fiber reinforced resin layer 19 is composed of the second fiber and the second resin. As the second fiber reinforced resin layer 19, for example, a glass fiber reinforced resin (GFRP) or an aramid fiber reinforced resin (AFRP) can be used. That is, the second fiber is composed of, for example, glass fiber or aramid fiber. In short, the second fiber is composed of fibers having a higher elongation rate (elongation at break) than the first fiber. As the second fiber, a fabric material (woven fabric), a UD material (unique directional material), and a plurality of UD materials laminated can be used. On the other hand, as the second resin, various synthetic resins such as a thermosetting resin and a thermoplastic resin can be used. The thickness of the second fiber reinforced resin layer 19 is, for example, about the same as or about half that of the first fiber reinforced resin layer 14.

As a method for producing the fiber reinforced resin molded product 10, for example, a general FRP molding method such as a hand lay-up method, an autoclave method, a vacuum bag method, or an RTM (Resin Transfer Molding) method can be used.

The effects of this embodiment will be described below.

(1) The fiber-reinforced resin molded product 10 is formed in a plate shape and has a core material 13 having a general portion 15 and curved portions 16, 17, 18 having a curvature larger than that of the general portion 15, and both sides of the core material 13. The first fiber reinforced resin layer 14 formed on at least one surface of the inside and having the first fiber is provided. The fiber-reinforced resin molded product 10 is further provided with a second fiber-reinforced resin layer 19 formed between the curved portions 16, 17, 18 of the core material 13 and the first fiber-reinforced resin layer 14 and having a second fiber. The elongation rate of the second fiber is higher than the elongation rate of the first fiber.

As shown in FIG. 4, for example, when an impact load is applied from the upper surface side to the ridge line portion (curved portion 17) of the bead portion 12 of the fiber reinforced resin molded product 10 (hood outer), the upper surface side is The compressive stress Sc acts, and the tensile stress St acts on the lower surface side. In this case, although not shown, the compressive stress Sc acts on the curved portions 16 and 18 located on both the left and right sides of the vehicle from the ridgeline portion (curved portion 17) of the bead portion 12 on the upper surface side. Tensile stress St acts on the lower surface side. Further, an out-of-plane stress (stress in the plate thickness direction) Sop also acts on the ridgeline portion (curved portion 17) of the bead portion 12 of the fiber-reinforced resin molded product 10. In FIG. 4, reference numeral 20 indicates an impactor used in a pedestrian protection test or the like.

For example, carbon fiber has a relatively high tensile strength, and has a relatively low compressive strength and an out-of-plane strength (interlayer strength) with respect to an out-of-plane load. Further, the general portion 15 of the core material 13 has a high contribution of compressive strength and tensile strength, and the curved portions 16, 17 and 18 having a larger curvature than the general portion 15 have a high contribution of out-of-plane strength. Therefore, in the curved portions 16, 17, and 18 of the core material 13, the rigidity against an external impact is generally weakened.

In the fiber-reinforced resin molded product 10 according to the present embodiment, a second fiber having a higher elongation rate than the first fiber is formed between the curved portions 16, 17, 18 of the core material 13 and the first fiber-reinforced resin layer 14. The second fiber reinforced resin layer 19 to have is formed. The second fiber (for example, glass fiber, aramid fiber) contained in the second fiber reinforced resin layer 19 has a higher elongation rate than the first fiber (for example, carbon fiber), and therefore has a lower surface against an external impact. It is possible to absorb the internal strain generated from the side and the upper surface side.

Therefore, according to the present embodiment, it is possible to provide the fiber reinforced resin molded product 10 capable of improving the rigidity against an external impact.

Further, since the second fiber reinforced resin layer 19 is formed between the curved portions 16, 17, 18 of the core material 13 and the first fiber reinforced resin layer 14, the core material 13 is cracked during molding using a mold. As a result, the manufacturing cost of the fiber-reinforced resin molded product 10 can be reduced.

(2) The first fiber contained in the first fiber reinforced resin layer 14 is a carbon fiber, and the second fiber contained in the second fiber reinforced resin layer 19 is a glass fiber or an aramid fiber.

By forming the first fiber reinforced resin layer 14 and the second fiber reinforced resin layer 19 in this way, it is possible to improve the rigidity of the fiber reinforced resin molded product 10 against an impact from the outside. That is, the glass fiber and the aramid fiber have a higher elongation rate than the carbon fiber, and can absorb the internal strain generated from the lower surface side and the upper surface side against an external impact. Therefore, according to the present embodiment, the curved portions 16, 17, and 18 of the core material 13 can be stiffened, and the rigidity of the fiber-reinforced resin molded product 10 against an external impact can be improved. ..

By the way, the fiber-reinforced resin molded product of the present invention has been described by taking an example in the above-described embodiment, but the present invention is not limited to this embodiment, and various other embodiments may be adopted without departing from the gist of the present invention. can.

For example, in the above-described embodiment, an example in which the "second fiber reinforced resin layer" is formed only on the upper surface side of the upper and lower surfaces of the core material is shown, but the present invention is not limited to this. As shown in FIG. 5, the "second fiber reinforced resin layer" may be formed only on the lower surface side of the upper and lower surfaces of the core material. Further, although not shown, "second fiber reinforced resin layers" may be formed on both the upper and lower surfaces of the core material. In short, it is preferable to form the "second fiber reinforced resin layer" on the upper and lower surfaces of the core material, which is the surface to be compressed when an impact load from the outside is applied (the surface on which compressive stress acts). ..

10 Fiber reinforced resin molded product 13 Core material 14 First fiber reinforced resin layer 15 General part 16 Curved part 17 Curved part 18 Curved part 19 Second fiber reinforced resin layer

Claims (2)

In a method for manufacturing a fiber-reinforced resin molded product, in which a fiber-reinforced resin molded product is molded by an RTM molding method.
The fiber-reinforced resin molded product is
A core material formed in a plate shape and having a general portion and a curved portion having a curvature larger than that of the general portion.
A first fiber reinforced resin layer formed on at least one of both sides of the core material and having the first fiber,
At least formed between the curved portion and the first fiber-reinforced resin layer of the core material, and a second fiber-reinforced resin layer having a high secondary fibers than the elongation elongation of said first fiber ,
The plate thickness of the core material at the curved portion is formed to be smaller than the plate thickness at the general portion.
A method for producing a fiber-reinforced resin molded product, wherein the second fiber-reinforced resin layer is formed on the surface of both sides of the core material that becomes the compression side when an impact load from the outside is applied. .. The first fiber is a carbon fiber and
The method for producing a fiber-reinforced resin molded product according to claim 1, wherein the second fiber is a glass fiber or an aramid fiber.

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