JP2004160744A - Left-over type resin pass medium made of reinforcing fiber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a left-over type resin pass medium made of a reinforcing fiber which improves resin impregnation properties and need not be removed by releasing after resin impregnation, in a resin impregnation process using a liquid resin. <P>SOLUTION: The left-over type resin pass medium 10 made of a reinforcing fiber is used in a method for molding a composite material using the liquid resin by installing the medium 10 along the lower face of a reinforcing fiber laminate 11. In addition, the resin pass medium 10 is three-dimensionally retained in form and kept left over even after molding by setting reinforcing fiber stripes 10a such as a carbon fiber, a glass fiber, a ceramic fiber or the like in order in a specified direction. Using the resin pass process by the resin pass medium 10, the impregnation properties of the resin into the reinforcing fiber laminate 11 are improved and the resin pass medium 10 need not be removed by releasing from the reinforcing fiber laminate 11 after resin impregnation. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
[Industrial applications]
INDUSTRIAL APPLICABILITY The present invention improves liquid resin impregnation into a fibrous base material for a composite material used for aerospace structures, architectural structures, automotive structures, marine structures, and other various structures requiring strength. And a resin path medium made of a residual type reinforcing fiber.
[0002]
[Prior art]
In general, as an aerospace / architecture structure, an architectural structure, an automobile structure, a ship structure, and various other structures requiring strength, a molding method using an autoclave using a prepreg is known. However, the loss of the base material is very large, the cost is high, and it is difficult to obtain a complicated shape. Recently, the RTM method (Resin Transfer Molding) in which a dry preform is impregnated with a liquid resin and molded is becoming popular. Above all, the VaRTM (Vacuum Assist Resin Transfer Molding) method, in which a dry preform is placed in a closed space formed by a molding bag and a mold and pressed against the mold with vacuum pressure, has been attracting attention as an inexpensive molding method.
[0003]
When impregnating and molding a fiber base material for a composite material with a resin by the RTM method or the VaRTM method, if the fiber density is increased in order to increase the strength of the fibrous structure, or if the base material has a complicated shape, the resin impregnation process is performed. Voids occur because the entire surface cannot be impregnated with the resin, or the resin impregnation time becomes extremely long, and sometimes the resin does not evenly spread over the entire substrate. Such a phenomenon is conspicuous when a large-sized fiber material for a composite material is impregnated with a liquid resin and molded to reduce the cost and strength, or when the base material is thick, etc. This also causes the strength to decrease significantly.
[0004]
[Problems to be solved by the invention]
Generally, when a molding method such as the RTM method or the VaRTM method is used, a resin flow path is secured as a means for instantaneously spreading the liquid resin over the entire preform under vacuum pressure, and the liquid resin is not crushed even when pressure is applied. A net-like resin pass medium made of polypropylene or the like is sold by various companies and used at the time of molding. However, since this resin path medium is made of a different material from the reinforcing fibers constituting the molded product, it is necessary to peel it off from the main body after molding and discard it. In addition, due to the increase in the size of the molded product, the operation itself of peeling is extremely difficult. Due to such a problem, molding of a fiber structure using the RTM method, the VaRTM method, or the like becomes expensive and it is difficult to provide stable strength. The difference of the resin pass medium according to the present invention from the above is that the resin pass medium is made of the same material as the reinforcing fibers of the fiber base material for a composite material, and thus can be left after molding. However, the inorganic fibers generally used as the reinforcing fibers are in the form of flat yarns, and have a problem in that they can be used as they are as a resin pass medium to ensure a sufficient resin flow path. In the present invention, it is possible to secure a resin flow path by holding the reinforcing fiber strip in a three-dimensional shape.
[0005]
On the other hand, various methods have been proposed in order to enhance the resin impregnation property of the fiber base material for a composite material itself. For example, a modified fiber sizing agent constituting a fiber structure (see Patent Document 1), a modified resin impregnation method (see Patent Document 2), and a structure of a fiber base material for a composite material. And those in which the fiber itself is devised (see Patent Documents 3, 4, 5, and 6) have been proposed.
[0006]
[Patent Document 1]
JP 2002-013069 A [Patent Document 2]
JP 2002-234078 A [Patent Document 3]
JP 2001-164441 A [Patent Document 4]
JP-A-10-217263 [Patent Document 5]
JP-A-09-207236 [Patent Document 6]
JP 2001-073241 A
These are inventions relating to the properties of the material of the reinforcing fiber itself, the fiber structure, and the fiber structure. It is trying to secure a road.
[0008]
Therefore, in the present invention, the reinforcing fiber is held in a three-dimensional shape, the resin flow path is secured, the resin impregnation property is improved, and further, there is no need to peel off after the resin impregnation, and the cost of the composite material can be reduced. An object of the present invention is to provide a residual type fiber-reinforced resin pass medium.
[0009]
[Means for Solving the Problems]
The residual type fiber-reinforced resin path medium of the present invention is a resin path medium used in a method of molding a composite material using a liquid resin, and pulls a three-dimensionally shaped inorganic reinforcing fiber strip in a predetermined direction. It is characterized by being aligned, and can be left after molding (claim 1).
[0010]
In addition, the residual-type reinforcing fiber resin path medium of the present invention is an inorganic reinforcing fiber sheet, in which the second reinforcing fiber sheet is spirally wound in the inorganic reinforcing fiber sheet constituting the reinforcing fiber resin path medium. Is three-dimensionally maintained (claim 2).
[0011]
In addition, the residual type reinforcing fiber resin path medium of the present invention is formed by spirally forming the same inorganic reinforcing fiber as the inorganic reinforcing fiber forming the reinforcing fiber resin path as the second reinforcing fiber. The reinforcing fiber strip is three-dimensionally maintained in shape by winding (claim 3).
[0012]
Here, the term "second reinforcing fiber strip" refers to an inorganic reinforcing fiber strip forming a resin path medium made of a reinforcing fiber, and a reinforcing fiber strip different from or similar to this is spirally formed. This means that the material is the same as that of the inorganic reinforcing fiber strip constituting the resin-passing medium made of the reinforcing fiber, as well as a different reinforcing fiber strip, or even if it is left after the resin impregnation, there is a problem in strength. Means that there are no reinforcing fiber strips. Since the second reinforcing fiber strip is constituted by the reinforcing fiber strip as described above, the operation of peeling off the reinforcing fiber resin pass medium after the resin impregnation becomes unnecessary.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of a residual type fiber-reinforced resin pass medium according to the present invention will be described with reference to the drawings.
[0014]
FIG. 1A shows a perspective view of a fiber base material for a composite material using a residual type fiber-reinforced resin pass medium 10 according to the first embodiment of the present invention. In the figure, reference numeral 11 denotes a unidirectional reinforcing fiber sheet (UD sheet) in which carbon fibers, glass fibers, aramid fibers, ceramic fibers, and other reinforcing fiber strips are aligned in one direction, and the direction in which the reinforcing fibers are aligned. For example, it is a reinforcing fiber laminate obtained by stacking differently such as 0 °, 90 °, + 45 °, and −45 °. The shape, size, and thickness of the reinforcing fiber laminate 11 can be arbitrarily set according to the application.
[0015]
Reference numeral 10 denotes a first embodiment of the present invention attached to the lower surface of the reinforcing fiber laminate 11, for example, as shown in FIG. , Ceramic fibers, and other inorganic reinforcing fiber strips 10a are aligned in a predetermined direction (the longitudinal direction in the illustrated example), and is a residual type fiber-reinforced resin path medium that can be left after molding. In addition, the alignment direction of the inorganic reinforcing fiber strips 10a in the resin path medium 10 made of the reinforcing fiber can be aligned in any direction and in a plurality of layers.
[0016]
In addition, when the reinforcing fiber laminate 11 is relatively thin or the fiber density is low, the reinforcing fiber resin path medium 10 is provided on one or both of the upper surface and the lower surface thereof. When the reinforcing fiber laminate 11 is thick or has a high fiber density, it may be provided on both surfaces and side surfaces. Further, the reinforcing fiber resin pass medium 10 may be added during the manufacturing process of the reinforcing fiber laminate 11 or may be added after the manufacturing process of the reinforcing fiber laminate 11 is completed.
[0017]
The above-mentioned fiber base material for a composite material secures a resin path by the inorganic reinforcing fiber shape 10a held in a three-dimensional shape of the reinforcing fiber resin path medium 10, and the reinforcing fiber laminate is obtained by a VaRTM method or an RTM method. When the liquid resin 11 is impregnated with the liquid resin and molded, the liquid resin flows instantaneously over the entire lower surface of the reinforcing fiber laminate 11 in contact with the reinforcing fiber resin path medium 10 using the reinforcing fiber resin path medium 10 as a resin path. Since the resin flows continuously in the thickness direction of the reinforcing fiber laminate 11, the resin can be uniformly and uniformly impregnated into the entire reinforcing fiber laminate 11 in a short time.
[0018]
For this reason, the composite material impregnated with the resin using the resin pass medium made of the reinforcing fiber has a partially unimpregnated portion (void) of the resin as in the related art, and the strength is partially insufficient or the resin is impregnated. The heat history of the resin is not optimal due to the low speed of the resin, and the phenomenon that the strength of the resin cannot be exhibited and the overall strength is less than the specified design strength disappears, and the entire base material is uniform And a reinforced composite material is obtained. In addition, since the resin path medium 10 made of the reinforcing fiber is made of the same reinforcing fiber as the composite material, the resin path medium generally used such as polyester or polypropylene can be peeled off after resin impregnation. In comparison, the resin path medium 10 made of a reinforcing fiber can be left without being peeled off after impregnation with the resin, and the cost of the composite material can be further reduced.
[0019]
FIG. 1 is a schematic view of an example of use in the present invention. FIG. 2 shows an exemplary embodiment of a resin path medium according to the present invention. Figure 2 is a reinforcing fiber strip 10a of first layer 10 ₁ are aligned in one direction, which is the form held in a three-dimensional shape that constitutes the resin path medium 10, pulling the reinforcing fibers strip 10b which is form holding the three-dimensional shape in the other direction aligning with it and the first layer 10 ₁ of a resin path medium having a two-layer structure in which the other first layer 10 ₂ constituted by superposing in different directions. The resin path medium 10 shown in FIG. 2 is formed by means such as knitting, stitching, or weaving.
[0020]
FIG. 3 is an enlarged perspective view of a main part of the residual type fiber-reinforced resin path medium 20 according to the second embodiment of the present invention. In the figure, as described above, a second reinforcing fiber strip 22, for example, an inorganic reinforcing fiber strip such as carbon fiber, glass fiber or ceramic fiber, or an aramid fiber or polyester Fibers, high-strength polyarylate fibers, and other fiber strips that have no problem in strength even when left behind after resin impregnation are spirally wound.
[0021]
Therefore, the reinforcing fiber resin path medium 20 is configured by spirally winding the second reinforcing fiber strip 22 around the inorganic reinforcing fiber strip 21 serving as the base material. It is held in a three-dimensional shape, and the resin pathability is improved. In particular, since the second reinforcing fiber strip 22 is made of inorganic reinforcing fiber or a fiber strip having no problem in strength even if it is left, the resin path medium 20 made of the reinforcing fiber is left as it is without peeling and removing after resin impregnation. It is possible to reduce the cost of the composite material.
[0022]
FIG. 4 is an enlarged perspective view of a main part of a residual type fiber-reinforced resin path medium 30 according to a third embodiment of the present invention. In the figure, 31 is formed by spirally winding an inorganic reinforcing fiber strip 31 made of the same base material as described above and a second inorganic fiber strip 32, so that the inorganic reinforcing fiber strip is three-dimensional as described above. Since the shape is maintained, a resin flow path is secured. In particular, since the second reinforcing fiber strips 32 are made of inorganic reinforcing fibers, it is possible to leave the reinforcing fiber resin pass medium 30 as it is without peeling and removing it after resin impregnation, and to reduce the cost of the composite material. .
[0023]
【The invention's effect】
According to the residual type fiber-reinforced resin path medium of the present invention, a resin path medium used in a method of molding a composite material using a liquid resin, wherein the reinforcing fiber strip held in a three-dimensional shape is moved in a predetermined direction. The resin path is secured by the reinforcing fiber resin pass medium because the resin path medium can be retained even after the molding, and a resin path medium made of a reinforcing fiber excellent in resin impregnation can be obtained. In addition, since this reinforcing fiber resin pass medium is made of reinforcing fibers, it is not necessary to peel and remove the resin after impregnation, and it can be left as it is. The manufacturing cost of the composite material can be reduced.
[0024]
Further, according to the residual type reinforcing fiber resin path medium of the present invention, in the inorganic reinforcing fiber strips constituting the reinforcing fiber resin path medium, the second reinforcing fiber strip is spirally wound to form the inorganic reinforcing fiber. Since the fibers are characterized by having a three-dimensional shape, the second reinforcing fibers are spirally wound around the inorganic reinforcing fibers, so that the residual reinforcing fibers have improved resin pathability. A resin pass medium is obtained.
[0025]
Further, according to the residual type reinforcing fiber resin path medium of the present invention, the same inorganic reinforcing fiber as the inorganic reinforcing fiber forming the reinforcing fiber resin path medium is spirally formed as the second reinforcing fiber. By winding in a shape, the inorganic reinforcing fiber strips are characterized in that they have a three-dimensional shape, so that the resin composition is improved by the spiral configuration of the inorganic reinforcing fiber strips and the second inorganic reinforcing fiber strips. Thus, a residual type resin path medium made of a reinforcing fiber is obtained.
[Brief description of the drawings]
FIG. 1A is a perspective view of a fiber base material for a composite material using a reinforcing fiber resin pass medium according to a first embodiment of the present invention,
(B) is a perspective view of the residual type reinforcing fiber resin path medium according to the first embodiment of the present invention.
FIG. 2 is an enlarged perspective view showing a residual type fiber-reinforced resin pass medium according to a typical embodiment of the present invention.
FIG. 3 is an enlarged perspective view of a main part of a resin path medium made of a reinforcing fiber according to a second embodiment of the present invention.
FIG. 4 is an enlarged perspective view of a main part of a reinforcing fiber resin path medium according to a third embodiment of the present invention, in which an inorganic reinforcing fiber strip and a second inorganic fiber strip serving as base materials are spirally wound around each other. It is.
[Explanation of symbols]
10, 20, 30 Remaining type fiber-reinforced resin pass media 10a, 10b Layers composed of inorganic fiber reinforcements 10 ₁ , 10 ₂ Layer 11 composed of inorganic fiber reinforcements 11 Reinforcement fiber laminate 21 Reinforcement fiber-reinforced resin path medium Fiber strip 22 Second reinforcing fiber strip 31 spirally wound around the inorganic reinforcing fiber strip forming the reinforcing fiber resin path medium Inorganic reinforcing fiber strip 32 forming the reinforcing fiber resin path medium 32 Reinforcing fiber resin path medium And the second inorganic reinforcing fiber wound spirally with each other

Claims (3)

A resin path medium used in a method of molding a composite material using a liquid resin, which is obtained by aligning inorganic reinforcing fibers in a three-dimensional shape in a predetermined direction, so that the residual mold can be retained even after molding. Fiber resin path medium. The inorganic reinforcing fiber strip constituting the resin path medium made of the reinforcing fiber, wherein the inorganic reinforcing fiber strip is three-dimensionally maintained by spirally winding the second reinforcing fiber strip. The resin pass medium made of the reinforcing fiber described in the above. As the second reinforcing fiber, by spirally winding the same inorganic reinforcing fiber as the inorganic reinforcing fiber forming the resin path medium made of the reinforcing fiber, the inorganic reinforcing fiber is three-dimensionally retained. The resin path medium made of a reinforcing fiber according to claim 2, characterized in that:

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