JP4168734B2 - Preform substrate, preform and method for molding fiber reinforced plastic - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a preform base material suitable for fiber-reinforced plastics, and a preform and fiber-reinforced plastic. Cuck's The present invention relates to a molding method.
[0002]
[Prior art]
Aircraft weight reduction is required to improve aircraft fuel efficiency and payload, and not only secondary structures such as spoilers, ailerons, wing trunk fairings and elevators, but recently horizontal stabilizers and vertical stabilizers for the tail In addition, fiber reinforced plastics, especially carbon fiber reinforced plastics, have been put to practical use for primary structures of floor support girders. Furthermore, in recent years, attempts have been made to replace primary duralumin with carbon fiber reinforced plastics in order to reduce the weight and cost of the primary large structures such as skins and stringers of the main wing.
[0003]
As primary structural materials for aircraft, mechanical properties such as tensile strength, tensile elastic modulus, compressive strength, compressive elastic modulus and impact fracture toughness of carbon fiber reinforced plastics are required, and at the same time, to achieve cost reduction Requires a molding method that can achieve cost reduction and a reinforcing fiber material adapted to this molding method.
[0004]
As a low-cost molding method, a vacuum bag molding method has recently attracted attention over an autoclave molding method in which a conventional prepreg laminate is bagged and heated and pressurized in an autoclave while holding the laminate under vacuum. In this method, a reinforcing fiber material not adhering to the matrix resin is laminated, and a resin diffusion medium is placed on the laminated body, these are bagged with a film, and the resin is passed through the diffusion medium while keeping the inside vacuum. It seems to be suitable as a molding method of a molded body having a large area.
[0005]
However, if the reinforcing fiber material such as a woven fabric is simply laminated, the fracture toughness between the layers cannot be ensured when it is formed into a fiber reinforced plastic. That is, the fiber reinforced plastic made of continuous carbon fibers is excellent in the mechanical properties in the fiber axis direction, but the mechanical properties rapidly decrease as the distance from the fiber axis increases. As a countermeasure, for example, the fiber axis direction in which the mechanical characteristics become a quasi-isotropic base material is the length (0 °) direction, the width (90 °) direction, or oblique (± 45) of the FRP (fiber reinforced plastic) molded body. (°) laminated and molded in the direction. However, when an impact in a direction perpendicular to the plane is applied to such a molded plate, for example, the mechanical properties in the plane direction of the 0 ° layer and the 45 ° layer are extremely different, so the deformation of the 0 ° layer and the 45 ° layer is different, Large cracks may occur between the layers, and the compressive strength of the molded plate is greatly reduced. The primary structure of an aircraft is required to have high reliability. Currently, structural materials made of duralumin are inspected for damage and cracks by regular visual observation. However, unfortunately, carbon fiber reinforced plastics are black and opaque, so it is impossible to visually observe the occurrence of cracks caused by stones that rise during take-off and landing, tool drops during assembly and repair, and collisions during transportation during assembly. The damage status cannot be detected.
[0006]
Further, the vacuum impregnation molding method is suitable as a molding method for aircraft wing skin materials having a large area, but since the skin material is 20 mm to 30 mm and thick, the number of laminated fabrics and the like is as large as 80 to 200, The resin does not flow to the opposite surface of the diffusion medium of the laminate, and a defect of poor resin impregnation occurs.
[0007]
Further, in order to improve the resin impregnation property, if the woven material is a two-way woven fabric in which the reinforcing fiber yarns are arranged in two directions, the warp direction and the weft direction, and the resin can be impregnated from the open space, Even a thick fiber reinforced plastic can be impregnated with a resin by a vacuum impregnation molding method. However, in such a woven fabric, the reinforcing fiber yarn extending in the warp direction is thickly crimped (bent) by a thick weft, and when this is formed, stress concentrates on the crimped portion, and the tensile strength and compressive strength are reduced. The predetermined strength as the structural material does not appear, and the design strength becomes low. Therefore, the structural material needs to be designed to be thick, and there is a problem that weight reduction cannot be achieved.
[0008]
In addition, since a large structural material such as a main wing skin material is large, for example, having a width of 5 to 7 m and a length of 20 m to 30 m, for example, even if a unidirectional fabric having good mechanical properties is laminated, A large number of fabrics with a width of about 100 cm in the length direction are laminated in multiple directions such as 0 ° direction, + α ° (normally + 45 ° direction), -α ° (normally -45 ° direction) and 90 ° direction. Despite the excellent labor-saving molding method such as folding and vacuum bag molding, it requires a lot of man-hours to laminate reinforcing fiber materials, and laminates reinforcing fiber materials such as long fabrics. Therefore, the fiber material, that is, the reinforcing fiber yarn is bent and it is difficult to laminate straightly.
[0009]
On the other hand, as a multiaxial fabric, Patent Document 1 discloses a multiaxial fabric in which reinforcing fiber yarns are expanded, a tape in which this state is fixed with a binder or the like is laminated in multiple layers and integrated with stitch yarns. Although disclosed, since such a fabric does not have a gap for resin impregnation, there is a problem that sufficient impregnation cannot be secured even if a thick fiber reinforced plastic is molded by a vacuum bag molding method. It was.
[0010]
In addition, multiaxial fabrics are also known in which reinforcing fiber yarns arranged in parallel are laminated in multiple directions in a sheet shape and stitched together with stitch yarns, but when reinforcing fiber yarns are arranged in parallel in a sheet shape Each thread hooked on the pin is free until the position is fixed with the stitch thread, and it is difficult to arrange all the threads accurately in the arrangement, and there is a problem that a gap is formed between the threads. . Furthermore, this state becomes more prominent because the yarn length in a free state increases as the width of the multiaxial fabric increases, and the mechanical properties deteriorate when fiber-reinforced plastic is used, resulting in a problem of lack of reliability. was there.
[0011]
[Patent Document 1]
JP-T-2001-516406 (Claims)
[0012]
[Problems to be solved by the invention]
Therefore, in view of the background of such prior art, the object of the present invention is that a large, thick fiber-reinforced plastic molded article is inexpensive, can be produced with good productivity, has excellent reliability, and has a tensile strength and a tensile modulus when molded. Preform substrate and preform with excellent mechanical properties such as compression strength, compression modulus and impact fracture toughness and How to mold fiber reinforced plastic The law It is to provide.
[0013]
[Means for Solving the Problems]
In order to solve the above problems, the present invention employs the following means. That is, in the preform base material according to the present invention, the reinforcing fiber yarns are parallel to each other in the length direction. And the gap between adjacent reinforcing fiber yarns is a substantially uniform gap of more than 0.1 mm and less than 1.0 mm over the entire width of the fabric. Array and at least on one side , The main component is a thermoplastic resin, the subcomponent is a thermosetting resin, and the thermoplastic resin is at least one selected from polyamide, polysulfone, polyethersulfone, polyetherimide, polyphenylene ether, polyimide, polyamideimide, and phenoxy. And a glass transition temperature of 50 to 150 ° C. It consists of the unidirectional textile base material which particle | grains adhere | attach, many said unidirectional textile base material cross-laminates, and consists of what is integrated by the integration means.
[0015]
Further, the unidirectional woven fabric has reinforcing fiber yarns on both sides of a sheet surface of a yarn group in which reinforcing fiber yarns that do not have a bending in which stress is concentrated are aligned in parallel in one direction and in a sheet shape. A unidirectional non-crimp fabric in which weft-direction auxiliary yarn groups are located, and the weft-direction auxiliary yarn groups and the warp-direction auxiliary yarn groups parallel to the reinforcing fiber yarns form a woven structure to hold the yarn groups together. It is preferable that
[0016]
The integration means is preferably a stitch.
[0017]
Moreover, it is preferable that the cross lamination angle includes at least a 0 ° layer with respect to the length direction of the preform substrate.
[0018]
Further, it is preferable that the cross lamination angle includes at least two directions of + α ° layer and −α ° layer with respect to the length direction of the preform substrate.
[0019]
In addition, it is possible to adopt a configuration in which the number of layers is not uniform with respect to the length direction of the preform base material and is increased or decreased from the middle.
[0020]
The reinforcing fiber yarn is preferably carbon fiber, but is not limited thereto. When using carbon fiber, Said unidirectional textile substrate Reinforcing fiber The yarn is The number of filaments is more than 12,000 and less than 25,000 , Tensile modulus exceeds 280 GPa and is less than 500 GPa, and fracture strain energy is 53 MJ / m ^Three More carbon fiber The weft yarn has a fineness of more than 6 dtex and less than 70 dtex It is preferable.
[0021]
As a preferred embodiment, the warp yarn is a carbon fiber yarn, the fineness of the weft direction auxiliary yarn is more than 6 dtex and less than 70 dtex, and the density of the weft direction auxiliary yarn is 0.3 / cm. And less than 6.0 fibers / cm, and the basis weight of the carbon fiber is 100 g / m ² Over 350g / m ² The structure which is less than can be mentioned. Among them, the fineness of the weft direction auxiliary yarn is more than 15 dtex and less than 50 dtex, the density of the weft direction auxiliary yarn is more than 1.0 yarn / cm and less than 4.0 yarn / cm, and the weight of the carbon fiber is small. 180 g / m ² Over 210g / m ² It is preferable that it is less than.
[0022]
The particles preferably have a function of imparting interlayer toughness of fiber reinforced plastic and have a melting point or glass transition temperature of more than 50 ° C. and less than 150 ° C.
[0023]
Moreover, it is preferable that it is more than 2% and less than 20% with respect to the weight of the reinforcing fiber which comprises the said unidirectional textile base material as the adhesion amount of particle | grains.
[0024]
The present invention also provides a laminate in which a plurality of preform substrates as described above are laminated, and each preform substrate is laminated without any breaks over the entire surface of the laminate.
[0025]
In addition, the preform according to the present invention comprises a plurality of preform substrates as described above, and a woven fabric substrate and / or a preform substrate are bonded to each other.
[0026]
In this preform, it is preferable that the preform base material is laminated seamlessly over the entire surface of the preform.
[0027]
Further, the reinforcing fiber volume fraction Vpf in the preform is preferably more than 45% and less than 60%.
[0028]
Moreover, it is preferable that the gap | interval of the said reinforced fiber yarn which adjoins the unidirectional textile base material which comprises the said preform exceeds 0.1 mm and is less than 1.0 mm.
[0029]
The method for molding a fiber reinforced plastic according to the present invention includes laminating a predetermined number of the above-mentioned preform base materials on a molding die, or placing the above-mentioned preform base material laminate on a molding die, and placing the resin on the molding die. After placing the medium that diffuses in the direction, cover the whole with a bag film, and then reduce the pressure inside the bag film to diffuse the liquid thermosetting resin on one side of the laminated preform substrate. The method comprises impregnating a preform base material with a resin and curing.
[0030]
The fiber-reinforced plastic molding method according to the present invention includes the above-described preform laminated on a mold, a medium on which the resin is diffused in the surface direction is placed thereon, the whole is covered with a bag film, and then the bag The method is characterized in that the inside covered with the film is in a reduced pressure state, a liquid thermosetting resin is diffused on one side of the laminated preform, and the preform is impregnated with the resin and cured.
[0031]
In such a fiber-reinforced plastic molding method according to the present invention, the thermosetting resin is an epoxy resin, the resin and the mold and the preform substrate or preform are heated, and the resin viscosity is lowered to impregnate the resin. It is preferable to improve.
[0033]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic perspective view of a unidirectional fabric base material 1 constituting a preform base material according to an embodiment of the present invention. In FIG. 1, a unidirectional fabric base material 1 has reinforcing fiber yarns 2 arranged in the warp direction, and thin weft yarns 3 as transverse auxiliary yarns are alternately crossed with the warp yarns to adjoin each other. A flat structure is formed with a gap A formed between the fiber yarns. Particles 4 adhere to the surface of the unidirectional fabric, and a gap A is formed between adjacent reinforcing fiber yarns.
[0034]
FIG. 2 is a schematic perspective view showing another embodiment of the unidirectional textile substrate 1. In FIG. 2, a unidirectional fabric base 1 has reinforcing fiber yarns 2 that are not bent so that stress is concentrated, arranged in a sheet shape in parallel in one direction, and the reinforcing fiber yarns on both sides of the sheet surface. A thin weft thread 3 that intersects with the reinforcing fiber yarns and the warp direction auxiliary yarns 5 in parallel with the reinforcing fiber yarns form a woven structure to integrally hold the reinforcing fiber yarns. The unidirectional non-crimp fabric has particles 4 attached to the surface of the unidirectional non-crimp fabric, and a gap A is formed between adjacent reinforcing fiber yarns.
[0035]
As shown in FIGS. 1 and 2, the case where the reinforcing fiber yarns of the warp yarn and the weft yarn are integrated in a plain structure and a non-crimp structure as the unidirectional woven material forming the unidirectional woven base material has been described. There may be.
[0036]
The reinforcing fiber yarn used in the present invention is a multifilament yarn, and the type thereof is not particularly limited, and examples thereof include glass fiber, organic (polyaramid, PBO, PVA, PE, etc.) fiber or carbon fiber. . In particular, carbon fibers are excellent in specific strength and specific elastic modulus and excellent in water absorption resistance, and are therefore preferably used as aircraft structural materials and reinforcing fiber yarns for automobiles.
[0037]
Among these, when the carbon fiber is high toughness, the impact absorption energy of the fiber reinforced plastic to be molded becomes large, so that it can be applied as a primary structural material for aircraft. That is, the tensile modulus (E) measured in accordance with JIS-R-7601 is more than 280 GPa and less than 500 GPa, and the fracture strain energy (σ ² / 2E, σ: tensile strength measured according to JIS-R-7601) is 53 MJ / m ^Three The above is preferable.
[0038]
When carbon fiber is used as the reinforcing fiber yarn, the number of filaments is preferably more than 12,000 and less than 25,000, and the yarn fineness is preferably more than 800 tex and less than 1,800 tex. Within such a range, there is an advantage that high-performance carbon fibers can be obtained relatively inexpensively because the form of the unidirectional woven fabric is stable and an appropriate gap is easily formed between adjacent yarns.
[0039]
Moreover, it is preferable that the reinforcing fiber yarn in the present invention is substantially untwisted from the viewpoint of the high reinforcing fiber volume ratio and the expression rate of mechanical properties of the molded composite material.
[0040]
The weft yarn used in the present invention is nylon 6 fiber, nylon 66 fiber, nylon 11 fiber, nylon 12 fiber, polyester fiber, polyaramid fiber, polyphenylene sulfide fiber, polyetherimide fiber, polyether sulfone fiber, polyketone fiber, polyether ketone. It is preferable that the weft is mainly composed of at least one selected from fibers, polyether ether ketone fibers and glass fibers. Of these, nylon 66 is preferred because it has good adhesion to the resin and a fine yarn can be obtained by stretching.
[0041]
In addition, the weft yarn of the unidirectional textile base material in the present invention is preferably a multifilament yarn. When it is a multifilament yarn, the fineness (diameter) of the filament single yarn can be reduced. When this is used in a substantially untwisted state, the weft yarn in the woven fabric is in a form in which filament single yarns are arranged in parallel without overlapping each other in the thickness direction, and the thickness of the weft yarn is reduced, Crimps due to crossing or crossing of reinforcing fiber yarns and weft yarns are reduced, and the straightness of the reinforcing fiber yarns is increased in the fiber reinforced plastic, resulting in high mechanical properties.
[0042]
From the same viewpoint, the thickness of the weft yarn is preferably as thin as possible, and the fineness of the weft yarn is preferably more than 6 dtex and less than 70 dtex. More preferably, it is more than 15 dtex and less than 50 dtex. Originally, in the present invention, the major role played by the weft yarn is to form a gap between adjacent reinforcing fiber yarns and to maintain the shape of the fabric substrate. A thick weft yarn is not preferable because the reinforcing fiber yarns are crimped in the fiber reinforced plastic and the straightness of the yarns is lowered.
[0043]
Further, the density of the weft yarn is preferably more than 0.3 / cm and less than 6.0 / cm, and more preferably more than 2.0 / cm and less than 4.0 / cm. If the density of the weft yarn is low, the fabric will come into contact with the rolls or guide bars during weaving or in the powder spraying process, resulting in disturbance of the weft yarn, and adjacent reinforcement that will become the resin flow path during vacuum bag molding It is not preferable because the gap between the fiber yarns is reduced and the impregnation property of the resin is deteriorated. Further, when the density of the weft yarn is increased, crimping of the reinforcing fiber yarn of the warp yarn is increased, the amount of the weft yarn fiber is increased, and the heat resistance of the fiber reinforced plastic is lowered by moisture absorption or the like, which is not preferable.
[0044]
In order to improve the adhesion with the resin, the weft used in the present invention removes the process oil adhering when spinning the fiber by scouring treatment, etc. It is preferable to set the dry heat shrinkage at 200 ° C. to 4% or less by heat treatment.
[0045]
Further, the warp auxiliary yarn in the non-crimp fabric of FIG. 2 prevents the expansion of the reinforcing fiber yarns arranged in the warp direction by the crossing of the warp auxiliary yarns and the weft yarns, and the interval between the adjacent reinforcing fiber yarns. Is to secure a resin flow path during vacuum bag molding. Also, in order to eliminate crimps due to the crossing of the weft yarns and the reinforcing fiber yarns, the reinforcing fiber yarns are arranged straight by crossing the weft yarns on both sides of the reinforcing fiber yarns and crossing the warp auxiliary yarns and the weft yarns. I will try to let you.
[0046]
The auxiliary yarn is preferably a glass fiber yarn that does not shrink due to particle adhesion or heating during molding. Further, since the auxiliary yarn has substantially no reinforcing effect on the fiber reinforced plastic, it is not necessary to make the auxiliary yarn so thick, and the fineness is preferably more than 100 dtex and less than 470 dtex. In addition, in order to ensure the resin flow path, it is possible to cover the auxiliary yarn and secure the resin flow path by twisting the covering yarn. The yarn used for the cover ring is nylon 6 fiber, nylon 66 fiber, nylon 11 fiber, nylon 12 fiber, polyester fiber, polyaramid fiber, polyphenylene sulfide fiber, polyetherimide fiber, polyether sulfone fiber, polyketone fiber, polyether ketone. Fiber, polyetheretherketone fiber, especially nylon 66 has good adhesion to the resin, and the fineness is more than 15 dtex and less than 50 dtex.
[0047]
The gap A between the reinforcing fiber yarns adjacent to each other in the woven fabric base in the preform base material is important for securing a resin flow path in the preform base material and the preform. The average interval between the reinforcing fiber yarns is preferably in the range of 0.1 to 1 mm. More preferably, it is 0.2-0.8 mm, More preferably, it is the range of 0.3-0.5 mm. Within such a range, the above-mentioned intra-layer flow path forming effect is sufficiently exhibited. Below that, it may not be fully expressed. On the other hand, if it is too wide, a large resin-rich portion is formed at the time of molding, which may lead to a decrease in the reinforcing fiber volume ratio, a decrease in mechanical properties (particularly fatigue strength), the occurrence of thermal cracks, and the like. In the measurement of the interval between the reinforcing fiber yarns, even if there is an auxiliary yarn between the reinforcing fiber yarns as in the case of a non-crimp fabric, the auxiliary yarn is thin and does not affect the resin flow so much. Measured.
[0048]
In addition, the gap A between adjacent reinforcing fiber yarns of the woven fabric base in the above was measured at 100 places using a measuring microscope capable of measuring with an accuracy of 0.01 mm, and the average value was taken as the gap value. . In addition, when it cannot measure with a measuring microscope, it can also measure with a stereomicroscope.
[0049]
The preferred range of the basis weight of the carbon fiber of the textile base material used in the present invention is 180 g / m. ² Over 350g / m ² Less, more preferably 180 g / m ² Over 210g / m ² Is less than.
[0050]
If the basis weight of the carbon fiber is too small, when obtaining a molded product having a predetermined thickness, the amount of fabric required is increased, the fabric manufacturing cost and the particle bonding cost are increased, and the number of layers is increased, resulting in a reduction in cost. I can not connect it. In addition, when the basis weight is increased, the gap between the yarns is reduced, and the thickness of the molded body is changed. Therefore, if the number of laminated fabric base materials is reduced from the middle, the change in thickness increases, and the reinforcing fiber yarn Since stress concentration may act on the cut part of the strip, it is not preferable.
[0051]
Although the particle | grains have adhere | attached on the textile fabric in the textile base material used by this invention, the amount of particle | grains exceeds 2% with respect to a reinforced fiber weight, and less than 20% is preferable. By adhering the particles in the above range, the reinforcing fiber yarns and weft yarns in the woven fabric and the auxiliary yarns in the non-crimp woven fabric are adhered to prevent the fabric from being misaligned and the form is stabilized. Furthermore, the adhesiveness of the textiles at the time of obtaining a preform base material and a preform by laminating the textile base materials is brought about.
[0052]
Moreover, the particle | grains of the said range play the role of a crack stopper in the fiber reinforced plastic obtained by laminating | stacking a textile base material. In particular, when the fiber reinforced plastic is subjected to an impact, it serves to suppress damage between the layers of the fabric, that is, to suppress the development of cracks, and the decrease in compressive strength after impact is reduced.
[0053]
When the amount of particles is 2% or less, a sufficient crack stopper effect cannot be obtained between the layers. Further, if the particle amount exceeds 20%, the volume ratio of the reinforcing fiber in the case of using fiber reinforced plastic becomes too small, and not only the mechanical properties are lowered, but also heating, pressurizing and preforming when bonding the particles. During heating and pressurization of the fiber densification treatment, particles are deformed to fill gaps in the yarn, and the flow path of the matrix resin may be crushed to impede impregnation, which is not preferable.
[0054]
Such particles may be adhered to the surface of the woven substrate, and may be adhered to one side of the woven substrate, or may be adhered to both sides. When manufacturing a textile base material at lower cost, the former is preferable.
[0055]
The smaller the average diameter of such particles (the average minor axis in the case of an ellipse), the more uniformly it can be dispersed on the surface of the woven fabric. Therefore, it is preferably 1 mm or less, more preferably 250 μm or less, and more preferably 50 μm. The following is more preferable.
[0056]
If the irregularities in the vertical direction are too large on the woven fabric surface of the particles adhered to the fabric substrate, the reinforcing fiber yarns located in contact with the surface may be bent. Is preferably in the range of 5 to 250 μm. More preferably, it is the range of 10-100 micrometers, More preferably, it is the range of 15-60 micrometers.
[0057]
The particles used in the present invention are heat-treated for adhesion of the particles to the fabric and high fiber density treatment of the preform. From the viewpoint of workability, the range of 50 to 150 ° C. The moth Having a lath transition temperature Is . More preferably, it is 70-140 degreeC, More preferably, it is the range of 90-120 degreeC.
[0058]
Here Uga Lass transition temperature Are measured from a differential scanning calorimeter (DSC), respectively. Ru Refers to the transition temperature to the lath state.
[0059]
The component of particle | grains will not be specifically limited if the handleability of a textile base material is improved and the mechanical property of the fiber reinforced plastic obtained using it is improved. The particles include various thermosetting resins and Heat Use plastic resin You The
[0060]
Use thermoplastic resin as main component of particles But, At least one selected from polyamide, polysulfone, polyethersulfone, polyetherimide, polyphenylene ether, polyimide, polyamideimide, and phenoxy It is. Of these, polyamide, polyetherimide, polyphenylene ether, and polyether sulfone are particularly preferable.
[0061]
Of particles composed of the above thermosetting resin and thermoplastic resin. The thermoplastic resin is the main component of the particles, and the blending amount is preferably 70 to 100% by weight. More preferably, it is 75-97 weight%, More preferably, it is 80-95 weight%. Impact resistance when the blending amount is less than 70% by weight In It may be difficult to obtain excellent fiber reinforced plastic. Moreover, when a thermoplastic resin is the main component, the adhesion of the particles to the woven fabric and the bondability may be inferior. In this case, it is preferable to add a small amount of a tackifier, a plasticizer or the like to the particles.
[0062]
FIG. 3 is a schematic partially broken perspective view showing a preferred embodiment of the preform base 6 according to the present invention. The unidirectional textile base material 1 to which the particles 4 are adhered in order from the lower surface side in the figure. ₁ Is in the + α ° direction of the length direction A of the preform substrate, ₂ In the 90 ° direction, _Three In the -α ° direction, _Four Is in the direction of 0 °, the textile substrate 1 _Five In the -α ° direction, ₆ In the 90 ° direction, ₇ In the + α ° direction, seven layers are cross-laminated so that particles exist between the respective layers, and these seven layers are stitched and integrated over the entire surface of the preform base material with stitch yarn 7 as an integration means. . The integration means is not limited to stitches, and the particles adhered to the textile substrate may be heated and spot-bonded in a spot shape to integrate them. In the case of lining up, the reinforcing fiber yarns on the concave side are locally bent because each layer does not slip.
[0063]
When the stitches are stitched together with stitch yarns, there is a degree of freedom for slippage between the respective layers. Therefore, the reinforcing fiber yarns are not locally bent even if they are along the curved surface. Examples of the stitch structure formed by the stitch thread in the stitching integration include single ring stitching and 1/1 tricot knitting. The stitching pitch of the stitch yarn with respect to the length direction of the preform base material is preferably more than 1 mm and less than 6 mm, and can be appropriately selected in consideration of the handleability and shapeability of the preform base material. Further, the stitching interval of the stitch yarn in the width direction of the preform substrate is preferably more than 2 mm and less than 40 mm. In addition, on the woven fabric base material used in the present invention, the particles are bonded, the reinforcing fiber yarns and the weft yarns are bonded, and the movement of the reinforcing fiber yarns is restricted, so to speak, it is in a state of being awakened. Therefore, when the stitch needles arranged linearly in the width direction on the fabric base material laminated in the 90 ° direction pierce the reinforcing fiber yarns in the 90 ° direction at a narrow interval, the reinforcing fiber at the portion where the needle has pierced Since the reinforcing fiber of the yarn may be broken, in such a case, the stitching interval may be larger than 10 mm and smaller than 40 mm, and the position of the reinforcing fiber yarn may slightly escape when the needle penetrates. preferable. It should be noted that if the interval between stitches exceeds 40 mm, the preform base material is not easily restrained by stitches, and the form becomes unstable.
[0064]
In addition, when the reinforcing fiber yarns in the 90 ° direction are damaged by the penetration of the needles, the arrangement of the needles is arranged in the width direction so that about one or two needles pierce the reinforcing fiber yarns in the 90 ° direction. May be arranged in an oblique direction.
[0065]
The stitch yarn used in the present invention is preferably a multifilament yarn, such as nylon 6 fiber, nylon 66 fiber, nylon 11 fiber, nylon 12 fiber, polyester fiber, polyaramid fiber, polyetherimide fiber, polyphenylene sulfide fiber, etc. Nylon 66 is preferable because it has good adhesion to the resin and a fine yarn can be obtained by stretching. The fineness of the stitch yarn is only required to be able to withstand yarn breakage at the time of stitch processing and to be integrated with stitches, and as small as possible. Preferably it is more than 14 decitex and less than 120 decitex. More preferably, it is more than 14 dtex and less than 85 dtex. If it is too thick, the stitch part becomes convex and not smooth fiber-reinforced plastics can be obtained, and the water absorption of the stitch yarn is large and the heat resistance is poor. In order to improve the adhesion of the stitch yarn used in the present invention to the resin, it is preferable to remove the process oil agent adhered at the time of spinning the fiber by a scouring treatment or the like.
[0066]
FIG. 3 illustrates a preform base material in which a unidirectional fabric base material is laminated on seven layers of a + α ° layer, a 90 ° layer, a −α ° layer, a 0 ° layer, a −α ° layer, a 90 ° layer, and a + α ° layer. However, the stacking angle and the number of stacked layers are not necessarily limited. For example, there are 9 layers such as 0 ° layer / + α ° layer / 0 ° layer / −α ° layer / 90 ° layer / −α ° layer / 0 ° layer / + α ° layer / 0 ° layer. It may be included.
[0067]
Moreover, although the said preform base material demonstrated the uniform lamination number of all 7 layers or 9 layers, even if the lamination number increases or decreases from the middle with respect to the length direction of a preform base material, Good. That is, the thickness of the structural material is not always constant. For example, the thickness of the skin material of an aircraft main wing skin material is gradually reduced in the length direction as it is separated from the fuselage. Therefore, when preparing a preform base material corresponding to the length of the main wing preform in advance, the −α ° layer, 90 ° layer, + α ° layer, and 0 ° layer are reduced one by one from the middle based on the structural design. It is possible to obtain a preform base material without any change in thickness. In particular, since the preform base material is multilayered, the preform base material with a uniform number of layers has been changed to a preform with a reduced number of preform base materials. Then, since the thickness of the preform base material per sheet is thick, the thickness changes suddenly, and stress concentration occurs at this sudden thickness change portion, resulting in a decrease in strength.
[0068]
Here, the bias angle α ° is preferably substantially 45 ° from the viewpoint of effectively laminating the preform base material in the length direction of the fiber-reinforced plastic structure and effectively performing shear reinforcement with the reinforcing fiber. The order of the lamination angle is not particularly limited, but the cracks between the layers of the fiber reinforced plastic due to the impact in the thickness direction of the laminate due to the anisotropy of the mechanical properties of each layer are made as small as possible. From the viewpoint of reducing the decrease in compressive strength, it is preferable that the intersection angle of the reinforcing fibers of adjacent layers is 45 °.
[0069]
In the present invention, the preform is a laminate in which a large number of preform base materials are laminated and the textile base material and the preforms are adhered to each other, and the preform base materials are laminated without being adhered. It is called.
[0070]
In addition, it is preferable that the preform base material is laminated on the entire surface of the preform seamlessly so that the cut portion of the reinforcing fiber yarn is not included in the preform base material laminate and the preform. For example, when forming a wide structure with a width of 5m to 8m, such as an aircraft main wing skin material, the width direction is preformed so that the 0 ° direction of the narrow preform substrate is the length direction of the main wing. Although the ends of the base material are overlapped and laminated, the weight of the overlapped portion increases and the intended weight reduction cannot be achieved, and reinforcing fiber yarns in the ± 45 ° direction and 90 ° direction are formed. It is not preferable because the stress is concentrated at the cut portion of the reinforcing fiber yarn and the strength is lowered. In addition, the laminate of the preform base material and the preform can be laminated so that the ends of the base material do not overlap with each other, but the ends of the base material are brought together. This is not preferable because the reinforcing fiber yarn in the direction is broken in the middle and stress concentration acts on the cut portion of the reinforcing fiber yarn, causing a decrease in strength.
[0071]
Therefore, in the case of a wide structure like the main wing, in order to prevent the overlap of the preform base and the insertion of the cut portion of the reinforcing fiber yarn, a wide preform base corresponding to the main wing width is used. It is preferable to laminate without breaks.
[0072]
Next, an example for producing such a preform substrate will be described.
For example, when preparing a preform base material laminated in seven layers of + α ° layer / 90 ° layer / −α ° layer / 0 ° layer / −α ° layer / 90 ° layer / + α ° layer, in the length direction Seven long woven fabric base rolls in which reinforcing fiber yarns are arranged and wound on a roll are prepared.
[0073]
Next, there is a belt in which pins are linearly implanted on both sides, and this belt moves to the stitch part and the winding part. Pull out while fixing the end of the fabric base material from the direction, hook it on the pin opposite to the roll installation side, and cut both ends of the fabric base material. Furthermore, while fixing the edge of the fabric base, pull it out so that there is no gap between the fabric base already pulled out and hooked on the pin, and so as not to overlap, the pin on the side opposite to the roll installation side The + α ° layer is formed by cutting both ends of the woven fabric substrate and repeating this process. Next, the fabric substrate is pulled out from the 90 ° direction, a 90 ° layer is formed on the + α ° layer that has already been formed, and a −α ° layer is formed on the + α ° layer / 90 ° layer in the same manner. . The 0 ° layer is supplied in parallel with the focus without being caught by the pin, reaches the stitch portion, and is temporarily trapped on the −α ° layer until the position is fixed, thereby forming the 0 ° layer. A needle is penetrated at the stitched part in a laminate of 7 layers in which -α ° layer, 90 ° layer, and + α ° layer are sequentially formed on + α ° layer / 90 ° layer / -α ° layer / 0 ° layer. Then, the preform base material of the present invention is produced by stitching and integrating with stitch yarns. In addition, the number of laminations is not uniform with respect to the length direction of the preform base material, and the preform base material that is increased or decreased from the middle is based on the structural design, -α ° layer, 90 ° layer from the middle, It is possible to manufacture by increasing or decreasing the supply of the + α ° layer and the 0 ° layer.
[0074]
Since the particles are bonded to the fabric base material used in the present invention, the reinforcing fiber yarns and the weft yarns are bonded in advance, and the movement of the reinforcing fiber yarns is restrained, so to speak, it is in a state of being awakened. The yarn arrangement is not disturbed when the preform substrate is produced. In addition, even in the case of a thin woven fabric, the shape of the woven fabric base material is stabilized by the adhesion of particles, and even when a wide preform base material is produced, wrinkles do not enter the woven fabric base material, and the quality is stable. A preform substrate can be produced.
[0075]
In forming, the laminate of the textile base is bulky due to sizing adhering to the reinforcing fiber yarns, entanglement of the reinforcing fibers, etc., so resin is injected into such a laminate by a vacuum bag forming method. However, since the pressure is small and the laminate cannot be sufficiently pressed, there are cases where the resin component is large, that is, the fiber reinforced plastic has a small volume content of reinforcing fibers. In such a case, for example, a preform in which a predetermined number of the preform substrates of the present invention are laminated is heated and pressurized to a temperature higher than the melting point or glass transition temperature of the particles to increase the fiber density, and the reinforcing fiber volume ratio in the preform It is preferable that Vpf is more than 45% and less than 60%. If it is 45% or less, the impregnation property of the resin by vacuum impregnation is good, but it becomes a fiber reinforced plastic with a small fiber volume content, the mechanical properties are also lowered, and it is difficult to achieve weight reduction of the structure. On the other hand, if it is 60% or more, the gaps between the yarns and the fibers become small and the resin does not flow easily.
[0076]
Here, the reinforcing fiber volume fraction Vpf indicates a value calculated by the following method.
Vpf = W1 / (ρ × T1) × 100 (%)
W1: Preform 1cm ² Weight of reinforcing fiber per g (g / cm ² )
ρ: density of reinforcing fiber (g / cm ^Three )
T1: Preform thickness measured in accordance with JIS 7602 under a load of 0.1 MPa (cm)
[0077]
It should be noted that the fiber volume content of the fiber reinforced plastic molded body obtained by molding the preform subjected to the high fiber densification treatment as described above is 52 to 62%, which is also applicable to aircraft structural materials such as main wing skin materials. The performance of fiber reinforced plastic can be fully demonstrated.
[0078]
In addition, because of the resin impregnation property, it is important that the gap between the reinforcing fiber yarns of the unidirectional fabric base material is secured in the preform base material. For example, a large number of preform base materials are laminated and bonded. Even in the preform before impregnating with the resin, it is not preferable that the gap between the yarns changes due to the fiber density increasing process of the preform to reduce the bulk, and it is not preferable that the gap becomes small. It is important that In the entire width of the woven fabric base material of the preform, the gap between the yarns of the woven fabric base material is preferably a substantially uniform gap of more than 0.1 mm and less than 1 mm. More preferably, it is in the range of more than 0.2 mm and less than 0.8 mm, more preferably more than 0.3 mm and less than 0.5 mm. Within such a range, the resin flows in the thickness direction of the preform and the preform is impregnated with the resin. If the gap is smaller than this, the viscosity of the resin will increase before the resin reaches the whole, or the resin will begin to harden, causing an unimpregnated portion of the resin, resulting in a defect and the molded body being rejected. In particular, if a large plastic structure such as a main wing is rejected, the economic damage will be enormous. Also, if the gap exceeds this range, the resin impregnation is good, but the reinforcing fiber yarns of the layer adjacent to this gap bite or drop during fiber densification treatment or molding, and the textile substrate, preform Although the reinforcing fiber yarns are straightly arranged in the state of the base material, the molded body is crimped (bent) due to the biting or dropping of the yarn into the gap, and the mechanical properties are deteriorated. Further, since the matrix resin enters the gap portion, the molded body becomes an excessive resin portion, and the excessive resin portion cracks due to fatigue or the like, which is not preferable. If the gap between the yarns is within this range, the resin flows through the gap to the next layer, the resin impregnation property is good, and a molded article having excellent mechanical properties can be obtained. It is. Moreover, it is preferable that a clearance gap is substantially uniform in the full width of a textile base material. If the gaps are non-uniform and large gaps are present sparsely, the resin from the gaps flows prior to other gaps, which is not preferable because an unimpregnated portion may be formed inside the preform.
[0079]
The preform base material, the laminate of the preform base material, and the preform can be used to form a fiber reinforced plastic by a conventionally known method. Among them, a resin transfer molding method or a vacuum bag molding method can be used. Is preferably used because a large molded product can be produced at low cost.
[0080]
Hereinafter, an embodiment of the method for producing the fiber-reinforced plastic of the present invention formed by vacuum bag molding using the preform of the present invention will be described.
[0081]
FIG. 4 is a cross-sectional view of one embodiment illustrating a method for molding fiber-reinforced plastic according to the present invention. In FIG. 4, a preform 9 is placed on a mold 8, a sheet that is peeled off after the resin is cured, a so-called peel ply 10 is laminated, and the resin is diffused over the entire surface of the preform. A medium 11 is placed. Around the preform, a large number of porous materials such as woven fabrics are laminated, and an edge breather 13 fitted with a vacuum pump air suction port 12 is stretched around. The whole is covered with a bag film 14, and air leaks. The periphery of the bag film is adhered to the mold with a sealing material 15 so that there is no possibility. A discharge port 17 for the resin injected from the resin tank is attached to the upper portion of the bag film, and is adhered with a sealing material 15 so that air does not leak from the attachment portion. The resin tank is filled with a syrup-like thermosetting resin at room temperature with a predetermined amount of a curing agent. Next, the preform covered with the bag film with the vacuum pump is brought into a reduced pressure state with a vacuum pressure of about 93310 to 101325 Pa, and then the valve 16 is released to inject the resin. The inside covered with the bag film is in a reduced pressure state, and the resin flow resistance in the surface direction of the medium is smaller than the thickness direction of the preform, so the resin first spreads over the entire surface of the medium and then in the thickness direction of the preform Impregnation proceeds. In this method, the distance that the resin must flow may be the thickness of the preform, so that the resin impregnation is completed very quickly. After the resin impregnation is completed, the valve 16 is closed and left at room temperature to cure the resin. After the resin is cured, the peel ply is peeled off, the medium and the bag film are removed, and the mold is removed from the mold to obtain a fiber reinforced plastic molded product.
[0082]
An example of the medium 11 used in the present invention is shown in FIG. The medium transmits the pressure reducing force in the bag to the preform and passes through the gap of the injected medium to spread the resin on the upper surface of the preform on the medium side. That is, when the resin is injected into the medium located between the bag film and the peel ply, in FIG. 5, the injected resin flows in the direction of the bar 18 through the gap between the X groups of bars 18 in contact with the bag film. Since the gap between the bars 19 having a rectangular cross section flows in the direction of the bar 19, the resin diffuses in all directions. Further, since the force applied to the bar 17 can be transmitted to the bar 18, the decompression force can be transmitted to the preform. As a specific medium, a mesh-like sheet made of polypropylene, polyethylene, polyester, polyvinyl chloride or metal is used. For example, it is a mesh-like resin film, a woven fabric, a net-like material, a knitted material, and the like, and several of these can be used as necessary.
[0083]
In addition, although the fiber material demonstrated the preform in the above, the laminated body of the preform base material which laminated | stacked many preform base materials and preform base materials said by this invention may be sufficient.
[0084]
The molding method described above largely falls within the category of vacuum bag molding method, but the conventional vacuum bag molding is performed in that resin is diffused to the entire surface of the preform substrate laminate or preform simultaneously with resin injection. Unlike the method, it is particularly suitable for molding large fiber-reinforced plastic molded products.
[0085]
The peel ply used in the molding method of the present invention is a sheet that is peeled off and removed from the fiber reinforced plastic after the resin is cured, but it is necessary to allow the resin to pass through, and the nylon fiber fabric, polyester fiber fabric, glass A fiber fabric or the like is used. Nylon fiber woven fabrics and polyester fiber woven fabrics are preferably used because they are inexpensive. However, in order to prevent oils and sizing agents used in manufacturing these fabrics from being mixed into the resin of fiber reinforced plastic, scouring is performed. In order to prevent shrinkage due to heating during curing, it is preferable to use a heat-set woven fabric.
[0086]
The edge breather used in the present invention needs to be able to pass air resin, and a nylon fiber fabric, a polyester fiber fabric, a glass fiber fabric, and a mat made of nylon fiber or polyester fiber can be used.
[0087]
The bag film used in the present invention needs to be airtight, and a nylon film, a polyester film, a PVC film, or the like can be used.
[0088]
In the molding method of the present invention, a thermosetting resin that is liquid at normal temperature, such as an epoxy resin, a vinyl ester resin, a phenol resin, or an unsaturated polyester resin, is usually used. An epoxy resin is preferably used in order to obtain a highly fiber-reinforced plastic. When the resin viscosity of the epoxy resin is small, the heat resistance generally deteriorates. Therefore, even when the resin viscosity is slightly high at room temperature, the mold temperature at the time of injection, the viscosity of the preform and the resin are preferably 70 to 100 ° C. The viscosity of the injected resin is preferably lowered so that the resin viscosity is 200 mPa · s or less. Subsequently, it is preferable that after resin injection, primary curing is performed at about 130 ° C., polymerization of the epoxy resin is advanced to at least a gel state, and then secondary curing is performed at a high temperature of about 180 ° C. By this method, it is possible to mold a fiber-reinforced plastic that has good resin impregnation, excellent heat resistance, and excellent mechanical properties such as toughness, strength, and elastic modulus.
[0089]
The scope of application of the fiber-reinforced plastic molded body obtained by the present invention is not particularly limited, but is suitable as a primary structural member of an aircraft such as an aircraft main wing (skin, stringer), floor support, fuselage, horizontal tail or vertical tail. Used.
[0090]
【Example】
Example 1
Reinforced fiber yarns with 24,000 filaments, yarn fineness of 1,030 tex, tensile strength of 5.8 GPa, tensile elastic modulus of 290 GPa, sizing adhesion of 0.5% by weight, and number of twists In this case, a 17-dtex nylon 66 filament yarn obtained by scouring a glass fiber yarn having a carbon fiber yarn of zero times as warp and a 22.5 dtex coupling agent as a warp auxiliary yarn is applied to the yarn. Covering yarn covered / coated at times / m, 17 decitex nylon 66 filament yarn with zero scouring twisted as weft yarn, carbon fiber yarn, auxiliary yarn warp density Are 1.84 pieces / cm, the weft density is 3 pieces / cm, and the carbon fiber basis weight is 190 g / m. ² A unidirectional non-crimp fabric was prepared. 27 g / m of particles having an average diameter of 120 microns on the upper surface of the fabric ² Was uniformly sprayed and adhered to the surface of the fabric by heating at 200 ° C. to prepare a fabric substrate.
[0091]
This fabric base material is laminated in the -45 ° direction, 90 ° direction, + 45 ° direction and 0 ° direction in succession, and 78 dtex nylon 66 filament yarn is used as the stitch yarn. A preform base material having a four-layer fabric base material was prepared so that the thickness was 10 mm and the pitch was 3 mm. As a result of the measurement, the gap between adjacent carbon fiber yarns of the woven fabric base constituting the preform base was 0.4 mm.
[0092]
Example 2
The preform base material was cut to be 50 cm in each of 0 ° direction and 90 ° direction, and 33 sheets were laminated while aligning the corners of the preform base material. This laminate was vacuum bagged with a film and subjected to a fiber densification treatment in an atmosphere at 80 ° C. for 1 hour to obtain a preform having a carbon fiber volume fraction Vpf of 49%. The gap between adjacent carbon fiber yarns in the preform was 0.35 mm, which was slightly narrowed by the fiber density increasing treatment.
[0093]
Example 3
Next, the mold in which the epoxy resin and the preform are set is heated to 80 ° C., the epoxy resin is injected for 1 hour, and then the resin is primarily cured at 130 ° C. for 2 hours, and then at 180 ° C. for 2 hours. After curing, vacuum bag molding was performed.
[0094]
The thickness of the fiber-reinforced plastic molding plate obtained is 25 mm and the volume content of carbon fiber is 55%. The resin is impregnated throughout the preform, and no voids are observed in the cross-sectional observation of the microscope. It was in a state where it could be used as a structural material.
[0095]
Comparative Example 1
Using the same carbon fiber yarn as in Example 1, it was attached to a support on a sheet arranged in parallel at a density of 1.84 pieces / cm, and the carbon fiber basis weight was 190 g / m. ² A unidirectional sheet was prepared. In addition, a support body is a mesh-like thing with the space | interval of 10 mm in the vertical direction and the weft direction to which the adhesive adhered to the glass fiber 22.5 decitex glass fiber yarn.
[0096]
Next, a comparative preform substrate was produced using the sheet under the same conditions as in the example. There was no gap between adjacent carbon fiber yarns of the unidirectional sheet constituting the comparative preform substrate, and it was 0 mm.
[0097]
Comparative Example 2
A preform that had been subjected to a fiber densification treatment by the same method as in Example 2 was produced. There was no gap between adjacent carbon fiber yarns in the preform, and it was 0 mm.
[0098]
Comparative Example 3
Next, a bag was formed by the same method as in Example 3. The bag film, peel ply, and resin diffusion medium were peeled off, and the molded body was observed. As a result, the resin was impregnated only in the preform of about 1 mm on the resin diffusion medium side, and the molded body to be impregnated with resin was completely free for 24 mm. The resin was not impregnated.
[0099]
The resulting fiber reinforced plastic molded plate was not impregnated with resin and was not in a very usable state as a structure.
[0100]
【The invention's effect】
As described above, according to the present invention, the following various effects can be obtained.
(1) The preform base material of the present invention comprises a unidirectional woven base material in which reinforcing fiber yarns are arranged in parallel to each other in the length direction and particles are bonded to at least one side, and the unidirectional woven base material Since a large number of sheets are cross-laminated and integrated by an integration means, a preform produced by laminating them in multiple layers can be manufactured at a low cost and with high productivity by greatly reducing the number of laminations.
[0101]
In addition, since the impregnation of the resin is good, it is possible to completely impregnate even a thick molded body, and there are particles between the fabrics, and a unidirectional fabric with a small crimp of reinforcing fiber yarn is used. Thus, a fiber-reinforced plastic molded article having excellent impact fracture toughness and excellent mechanical properties such as tensile strength, tensile elastic modulus, compressive strength, and compressive elastic modulus can be obtained.
[0102]
(2) In the preform and the laminate of the preform base material of the present invention, the preform base material is laminated seamlessly on the entire surface, so that the cut portion of the reinforcing fiber yarn does not exist in the preform and the laminate body. , A large molded article having excellent tensile strength and compressive strength can be obtained.
[0103]
(3) In the preform of the present invention, a predetermined number of preform substrates are laminated, and the woven fabric substrate and the preforms are bonded to each other. The reinforcing fiber volume fraction Vpf in the preform exceeds 45% and less than 60%. Therefore, it is possible to obtain a molded article with good resin impregnation and a high fiber volume content.
[0104]
(4) In the molding method of the present invention, a laminate of a preform base material and a preform are laminated on a mold, a medium for diffusing the resin in the surface direction is placed thereon, and then the whole is covered with a bag film, The fiber reinforced fiber is characterized in that the interior covered with a bag film is decompressed, a liquid thermosetting resin is diffused on one side of the laminate and preform, and the laminate and preform are impregnated and cured. Since it is a plastic molding method, a large molded article can be produced at a low cost, and a molded article without voids can be obtained.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view of a unidirectional textile substrate constituting a preform substrate according to an embodiment of the present invention.
FIG. 2 is a schematic perspective view of a unidirectional textile substrate constituting a preform substrate according to another embodiment of the present invention.
FIG. 3 is a schematic partially broken perspective view showing a preferred embodiment of a preform base material according to the present invention.
FIG. 4 is a cross-sectional view in one embodiment illustrating a method for molding a fiber reinforced plastic according to the present invention.
FIG. 5 is a schematic perspective view showing one embodiment of a resin diffusion medium used in the molding method of the present invention.
[Explanation of symbols]
1 Unidirectional textile substrate
1 ₁ Unidirectional textile substrate (+ α ° direction with respect to the length direction a of the preform substrate)
1 ₂ Unidirectional textile substrate (90 ° direction with respect to the length of the preform substrate)
1 _Three Unidirectional textile substrate (-α ° direction with respect to the length direction a of the preform substrate)
1 _Four Unidirectional fabric base (0 ° to the length of the preform base)
1 _Five Unidirectional textile substrate (-α ° direction with respect to the length direction a of the preform substrate)
1 ₆ Unidirectional textile substrate (90 ° direction with respect to the length of the preform substrate)
1 ₇ Unidirectional textile substrate (+ α ° direction with respect to the length direction a of the preform substrate)
2 Reinforcing fiber yarn
3 Weft
4 particles
5 Warp direction auxiliary thread
6 Preform base material
7 Stitch yarn
8 Mold
9 Preform
10 peel ply
11 Resin diffusion media
12 Air suction port
13 Edge Breather
14 Bag film
15 Sealing material
16 Valve
17 Resin outlet
18 X Group Bar
19 Y group bar
A Clearance between reinforcing fiber yarns
A Length direction of preform substrate

Claims (18)

The reinforcing fiber yarns are arranged in parallel with each other in the length direction , and the gaps between the adjacent reinforcing fiber yarns are arranged with a substantially uniform gap of more than 0.1 mm and less than 1.0 mm over the entire width of the woven fabric. , the main component and a thermoplastic resin, the secondary component and a thermosetting resin, at least the thermoplastic resin is polyamide, polysulfone, polyether sulfone, polyetherimide, polyphenylene ether, polyimide, polyamideimide, selected from phenoxy 1 a seed, made from one textile substrate particles is the glass transition temperature of 50 to 150 ° C. is adhered, the unidirectional fabric substrate is a large number of sheets cross-laminated, that have been integrated by integrating means , Preform substrate. The unidirectional woven fabric intersects the reinforcing fiber yarns on both sides of the sheet surface of the yarn group in which the reinforcing fiber yarns that are not bent so as to concentrate stress are parallel to each other in one direction and in a sheet shape. This is a unidirectional non-crimp fabric in which weft-direction auxiliary yarn groups are located, and the weft-direction auxiliary yarn groups and the warp-direction auxiliary yarn groups parallel to the reinforcing fiber yarns form a woven structure to hold the yarn groups together. The preform substrate according to claim 1 . The preform base material according to claim 1 or 2, wherein the integration means heats the particles adhered to the textile base material to cause spot adhesion in a spot shape. Said integrated means Ru stitch der, preform substrate according to claim 1 or 2. The preform substrate according to any one of claims 1 to 4, wherein the cross lamination angle includes at least a 0 ° layer with respect to a length direction of the preform substrate. The preform substrate according to any one of claims 1 to 5, wherein the cross lamination angle includes at least two directions of a + α ° layer and a -α ° layer with respect to a length direction of the preform substrate. Number of laminated layers are not uniform with respect to the longitudinal direction of the preform substrate, that has increased or decreased from the middle, preform substrate according to any one of claims 1 to 6. The reinforcing fiber yarn of the unidirectional fabric base has a filament number of more than 12,000 and less than 25,000, a tensile elastic modulus of more than 280 GPa and less than 500 GPa, and a fracture strain energy of 53 MJ / m. ^The preform substrate according to any one of claims 1 to 7 , which is a carbon fiber of ³ or more , and the weft yarn has a fineness of more than 6 dtex and less than 70 dtex . 5. The unidirectional woven fabric base material is a carbon fiber yarn, the fineness of the weft direction auxiliary yarn is more than 6 dtex and less than 70 dtex, and the density of the weft direction auxiliary yarn is more than 0.3 / cm. 0 lines / less than cm, and the basis weight of the carbon fibers Ru der less than 350 g / m ² exceed 100 g / m ^2, preform substrate of claim 8. The preform substrate according to any one of claims 1 to 9, wherein the particles have a function of imparting interlayer toughness of a fiber reinforced plastic and have a glass transition temperature of more than 50 ° C and less than 150 ° C. Wherein Ru less than 20% der exceed 2% by weight of reinforcing fibers attached amount constituting the unidirectional fabric substrate particles, preform substrate according to any of claims 1-10. Claim 1 preform substrate according to any one of the 11 is more number of lamination, that each preform substrate has been laminated seamlessly over the whole surface of the laminate, the laminate. According preform substrate according to any one of claim 1 to 11 is more number of lamination, between the textile substrate and / or the preform substrate that are bonded preform. The preform substrate, that have been stacked seamlessly over the entire surface of the preform, the preform of claim 13. Improvements in the preform fiber volume fraction Vpf is Ru less than 60% der exceed 45%, preform according to claim 13 or 14. A preform base material according to any one of claims 1 to 11 is laminated on a predetermined number of molds, or a laminate of the preform base material according to claim 12 is placed on a molding die, and a resin is placed thereon. After placing the medium that diffuses in the surface direction, cover the whole with a bag film, then reduce the pressure inside the bag film, and diffuse the liquid thermosetting resin on one side of the laminated preform substrate. A method for molding a fiber reinforced plastic, characterized in that a preform base material is impregnated with a resin and cured. The preform according to any one of claims 13 to 15 is laminated on a mold, and a medium for diffusing the resin in the surface direction is placed thereon, and then the whole is covered with a bag film, and then covered with a bag film. A method for molding a fiber reinforced plastic, characterized in that the inside is decompressed, a liquid thermosetting resin is diffused on one side of a laminated preform, and the preform is impregnated with the resin and cured. The thermosetting resin is an epoxy resin, heating the resin and mold and preform substrate or preform, is characterized by improving the resin impregnating ability to lower the resin viscosity, according to claim 16 or 17 Fiber reinforced plastic molding method.

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