JP5476916B2 - Manufacturing method of fiber reinforced plastic - Google Patents

Description

  The present invention relates to a method for producing a fiber reinforced plastic, and specifically relates to molding of a channel-shaped fiber reinforced plastic having at least corner portions.

  In recent years, the opportunity to use fiber reinforced plastics for structural members in order to reduce the weight of aircraft and automobiles has increased. The shape of the structural member may have a complicated shape such as an I, C, or T shape in order to increase the section modulus such as the moment of inertia of the section.

  As a molding method for successfully molding such a shape, there is a molding method for shaping a reinforcing fiber laminate along a mold. Of these, female molding is a molding method used when the dimensions and surface accuracy on the female mold side are required, and is a useful molding method for assembling parts on the female mold side of the molded product, but at the time of molding. Is difficult to shape, and FIG. As described in FIG. 1 and FIGS. 2 and 3 of Patent Document 2, the problem is that the corner portion of the fiber reinforced plastic becomes thick.

  As a forming method for solving this problem, Patent Document 1 introduces a method for reducing the thickness of the corner portion by applying an external force to the corner portion. However, in this method of applying external force, as the molded product becomes larger, the area to which external force should be applied increases, so the mechanism that supports the reaction force corresponding to the external force becomes large and requires a large space for installation. There are challenges. Patent Document 2 introduces a method of suppressing the increase in the thickness of the corner portion by suppressing the secondary material disposed on the reinforcing fiber substrate. Although the effect of suppressing the thickening is recognized, it cannot be said that the thickness of the reinforcing fiber substrate is positively controlled.

  In addition, methods such as Patent Documents 3 and 4 have been introduced as methods for applying no external force. Patent Document 3 introduces a method of placing a Ω-type cowl inside a bagging material and pressurizing the corner portion by suppressing the convex portion of the cowl with vacuum pressure. However, with such a method, it is difficult to apply a uniform pressure to the target position every time, and there is a possibility that the cowl deformed after the heat forming does not return to the original shape.

  Patent Document 4 introduces a method in which a preform is disposed in a female mold and a male mold having a GAP is disposed between the female mold and the top, and a method for thinning the corner is described. There is no real feasibility.

  Patent Document 5 is a molding method using a pair of upper and lower molds. The flexible upper mold that fits into the lower mold has a radius of curvature smaller than the radius of curvature of the inner bottom surface of the lower mold. Furthermore, a flexible cowl plate having a smaller radius of curvature than the bottom surface of the upper mold is disposed between the upper mold and the upper mold. Therefore, a method has been introduced in which when the upper mold is pressed in the lower mold direction, the prepreg is pressed along one point or line, and the cowl plate is sequentially pressed to the corner portion while being deformed. Considering the reaction force of the cowl plate, it can be said that in this method, when the corner part is pushed, the cowl plate is deformed to the maximum, so that the corner part is pressed less than the starting point. Therefore, it is considered that the effect of thinning the corner portion is slightly inferior.

  Patent Documents 6 and 7 introduce a method for controlling the plate thickness. Specifically, a method of controlling the thickness of the flat plate by disposing a spacer is disclosed. However, Patent Documents 6 and 7 describe only a thickness control technique for a flat plate, and do not describe a technique capable of uniformly controlling the thickness of a corner portion.

US2006 / 0017200 (Fig. 1, 2) JP 2008-230020 A (FIGS. 2 and 3) US2004 / 0047934 (FIG. 4) US2006 / 0068170 Publication (FIG. 2) Japanese Patent Laying-Open No. 2005-288756 (FIG. 3, 4) WO2008 / 040970 Publication US640660

  As described above, female molding has advantages such as easy assembly because the outside can be manufactured with high precision, but there is a problem that local thickening of the corner portion occurs. Several solutions have been introduced, but simple and effective methods have not been developed yet. For this reason, it is desired to develop a manufacturing method capable of suppressing the increase in thickness at the corner and further controlling the plate thickness.

The contents of the present invention include the following methods (1) to (7).
(1) A method for producing a fiber reinforced plastic, which is a method for producing a fiber reinforced plastic obtained by curing a matrix resin impregnated in a reinforced fiber laminate having a corner portion, comprising at least the following steps.
(A) Reinforcing fiber laminate arrangement step of arranging the reinforcing fiber laminate in a female mold having a corner portion (b) Pressure plate arrangement in which a pressure plate is arranged at least in the corner portion on the reinforcing fiber laminate. Step (c) Spacer arrangement step of arranging a spacer in the gap between the female die and the pressure plate at the end of the pressure plate (d) A sealing material is arranged on the periphery of the female die, and the whole is covered with a bagging material Bagging step (e) While vacuum suctioning the inside of the bagging material, the reinforcing fiber laminate is adsorbed to the female mold, and the reinforcing fiber laminate is thinned so that the spacer and the pressure plate are in contact with each other. Thinning step (2) Curing the matrix resin impregnated in the reinforcing fiber laminate with corners Comprising a method for producing a fiber-reinforced plastics, method for producing a fiber-reinforced plastic, characterized in that it comprises at least the following steps.
(A) Reinforcing fiber laminate placement step of placing the reinforcing fiber laminate in a female mold having a corner portion (b) Pressure with spacer having a spacer on at least one end on the reinforcing fiber laminate (C) a bagging step in which a sealing material is arranged on the periphery of the female mold and the whole is covered with a bagging material; and (d) vacuum-suctioning the inside of the bagging material while laminating the reinforcing fibers. A thinning step of thinning the reinforcing fiber laminate so that the body is adsorbed on the female die and the spacer is in contact with the surface of the female die. (3) The thickness of the spacer is determined by the arrangement of the reinforcing fiber laminate. wherein the thinner than the thickness of the laminate in the step (1) or manufacturing how a fiber reinforced plastic according to (2).
(4) In the bagging step, one or a plurality of injection ports for injecting the matrix resin are provided, and in the thinning step, the matrix resin is injected into the reinforcing fiber laminate. ) A method for producing a fiber-reinforced plastic according to any one of the above.
(5) The method for producing a fiber-reinforced plastic according to (4), wherein after injection of the matrix resin, at least one of the injection ports is switched to a vacuum suction port, and a part of the impregnated matrix resin is sucked.
(6) The method for producing a fiber-reinforced plastic according to any one of (1) to (5), wherein the resin fluidized layer is disposed on substantially the entire surface of the reinforcing fiber laminate not in contact with the female mold surface.
(7) The method for producing a fiber-reinforced plastic according to any one of (1) to (6), wherein the fiber-reinforced plastic has at least a C cross section.

ADVANTAGE OF THE INVENTION According to this invention, in the manufacturing method of the fiber reinforced plastic which has a corner part, suppression of thickness increase in a corner part and also the manufacturing method which can control board thickness are realizable. By using this manufacturing method, a fiber reinforced plastic having a uniform thickness and a high fiber volume content (V _f ) can be obtained even in the corner portion.

In the manufacturing method of the fiber reinforced plastic which concerns on this invention, it is sectional drawing which showed typically the case where an independent spacer is used. In the manufacturing method of the fiber reinforced plastic which concerns on this invention, it is sectional drawing which showed typically the case where an integrated spacer is used. It is sectional drawing which showed typically the form of the reinforced fiber laminated body which concerns on this invention. It is sectional drawing which showed typically the thinning process which concerns on this invention. It is sectional drawing which showed typically the fiber reinforced plastic obtained by this invention. It is sectional drawing which showed typically the fiber reinforced plastic obtained by the comparative example. It is the schematic diagram explaining the C-shaped cross-sectional member suitable for this invention.

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

  FIG. 1 is a cross-sectional view schematically showing a method for producing a fiber-reinforced plastic according to the present invention. The reinforcing fiber laminate 2 is arranged inside the female mold 1 having the corner portion 12, and the auxiliary materials such as the peel ply 3 and the resin diffusion medium 4 are arranged thereon, and the reinforcing fiber laminate 2 is formed into a predetermined shape. A plurality of pressure plates 5 to be arranged are placed. When the spacer 8 is an independent member, the spacer 8 is disposed at the end of the reinforcing fiber laminate 2. Thereafter, these members are covered with the bagging material 6, and the periphery of the bagging material 6 is sealed with the sealing material 7. The injection path 61 is connected to the injection port 10 at the upper end of the female mold 1 and the suction path 64 for vacuum suction by the vacuum pump 66 is connected to the suction port 9 so that the matrix resin 62 can be injected into the reinforcing fiber laminate 2. The injection path 61 and the suction path 64 are provided with an opening / closing valve 63 and a resin trap 65 for switching the path.

  The manufacturing method of the fiber reinforced plastic according to the present invention will be described more specifically for each process.

First, the reinforcing fiber laminate arranging step of arranging the reinforcing fiber laminate 2 in the female mold 1 having the corner portion 12 will be described. The reinforcing fiber laminate 2 used in the present invention is obtained by laminating a plurality of sheet-like materials containing reinforcing fibers such as carbon fibers, glass fibers, and aramid fibers. Unidirectional fabric with the sheet material, bidirectional fabric, multiaxial stitch base, a nonwoven fabric, include CSM (C ontinuous S trand M at ), which resin is pre-impregnated prepreg, before impregnation the dry substrate It may be. In order to obtain the effect of controlling the plate thickness of the present invention as the number of laminated reinforcing fiber laminates 2, it is preferable that the reinforcing fiber laminate 2 is at least 4 sheets (molded product plate thickness is 1 mm or more). The laminated structure is not particularly limited. As shown in the upper left of FIG. 3, it is preferable that the reinforcing fiber laminate 2 in which the sheet-like material is laminated in advance is arranged along the inner surface of the female mold 1. The arrangement method is not particularly limited, such as a hand layup method in which direct arrangement is performed manually, a method of automatic arrangement using a robot or the like.

  More preferably, as shown in the upper right of FIG. 3, a form of a preform 70 in which four or more reinforcing fiber laminates 2 are preliminarily shaped into a substantially female shape may be used. Since the preform 70 can be easily placed in the female mold 1, it is easy to ensure positioning accuracy and an orientation angle guarantee. The preform 70 here is a shape in which the reinforcing fiber laminate 2 is deformed. For example, if the prepreg is formed into a preform, the shape is formed using the tackiness of the material itself. In the case of a dry substrate, a method of heating and melting the resin material in a state where the resin material is applied between the layers and forming the shape, a reinforcing fiber laminate woven with a fibrous resin material can be used. Various methods such as a method of heating and melting a fibrous resin material in a shape-formed state, a method of sewing in a state of forming a reinforcing fiber laminate, and a method of enveloping fibers by needling can be used. Whichever material is used, the method is not particularly limited as long as the shape can be maintained.

  Next, the pressure plate arrangement process will be described.

  The pressure plate 5 is used for compressing (thinning) while keeping the plate thickness of the reinforcing fiber laminate 2 constant when vacuuming the reinforcing fiber laminate 2 described later.

  The pressure plate 5 may be placed directly on the surface of the reinforcing fiber laminate 2, or a secondary material may be sandwiched therebetween. For example, in resin injection molding to be described later, a peel ply 3 made of a cloth used for resin release is formed on the reinforcing fiber laminate 2, and a resin diffusion medium 4 (medium) for diffusing the injected resin on the surface of the reinforcing fiber laminate 2. ) May be arranged in this order.

  In the present invention, it is necessary to arrange the pressure plate 5 so as to cover at least the corner portion 12 so that the corner portion 12 can be reliably compressed. The shape of the pressure plate 5 is not particularly limited as long as the corner portion 12 is covered, but it is preferable that the pressure plate 5 is divided on the web 13 in the vicinity of the corner portion 12. If it is divided on the web 13 in the vicinity of the corner 12, the pressure plate 5 also moves following the change in the peripheral length of the reinforcing fiber laminate 2 caused by the change in the thickness of the corner 12 when vacuum suction is performed. can do.

  In addition, when there is a gap in the joint 15 generated by dividing the pressure plate 5, there is a concern that unevenness is generated on the surface of the reinforcing fiber laminate 2, but between the pressure plate 5 and the reinforcing fiber laminate 2. It is also possible to make the unevenness almost inconspicuous by sandwiching a secondary material that functions as a cushioning material or adjusting the interval between the joints 15 well. For example, if the resin diffusion medium 4 made of a thermoplastic resin is used as an auxiliary material, the surface unevenness at the joint 15 can be made inconspicuous by setting the gap 14 between 0.1 mm and 5 mm. . In addition, when using a thin secondary material such as the peel ply 3 having a thickness of 0.1 mm or less as a secondary material used as a cushioning material, the gap 14 is 0.1 mm or more and 2 mm or less. It is preferable to do. This is because the secondary material sandwiched between the pressure plate 5 and the reinforcing fiber laminate 2 is out of the plane by using the flexibility of the secondary material to provide an appropriate interval between the plurality of pressure plates 5. This is because deformation in the direction is suppressed. In addition, the space | interval 14 of a seam can be suitably adjusted according to the material and structure of a subsidiary material.

  In this way, it is conceivable to optimally design the interval 14 of the seam so as not to generate unevenness, but conversely, the unevenness is generated at a target position so as not to be buffered with other members, It is also possible to use this unevenness for positioning.

  Moreover, it is preferable that the shape of the flange 11 side including the corner part 12 among the divided pressure plates 5 has an L-shaped cross section from the viewpoint of weight reduction. If it is an L-shaped cross section, the plate thickness can be reduced, so that the weight can be reduced, and the handling property of the pressure plate 5 can be improved. Moreover, it is a preferable aspect because it can be easily manufactured by utilizing a bending process of a flat plate or a cutting from an L-shaped mold material. Specific examples of the material include a metal material such as iron and aluminum, or a material having a linear expansion coefficient close to that of the molded product, for example, CFRP or Invar material when the molded product is CFRP.

  Next, the spacer arrangement process will be described. The spacer 8 plays a role as a support that allows the reinforcing fiber laminate 2 to have a predetermined thickness and that the pressure plate 5 can uniformly compress the entire reinforcing fiber laminate 2. The spacer 8 is disposed in the gap with the female die 1 at the end of the pressure plate 5, specifically, at the upper end of the L-shaped cross section shown in FIG. The material of the spacer 8 is preferably selected from materials that do not undergo plastic deformation due to the applied surface pressure and are resistant to the matrix resin 62 to be applied. For example, if the matrix resin 62 is an epoxy resin, stainless steel, iron, aluminum It is preferable to use a metal material such as a fiber reinforced plastic. Moreover, it is preferable that the spacer 8 is provided with a release property (release agent or plating). If the mold release process is performed, it is not necessary to newly prepare a mold release material, and after the matrix resin 62 is cured, it can be easily separated from the female mold 1 and the bagging material 6 and reused.

  It is preferable that any or all of the spacer 8, the female die 1, and the pressure plate 5 are made of a magnetic material because the spacer 8 can be easily arranged and fixed. However, since ferrite-based magnets are fragile and may be damaged when used repeatedly, it is preferable to use a metal material or a stack of a magnet and a metal material for the detachable portion. When the spacer 8 is used alone, even if the spacer 8 is damaged by repeated use, it is only necessary to replace the spacer 8, and the entire jig such as the integrated pressure plate 21 described later can be replaced. Since it is not necessary to repair, it is preferable in terms of easy handling.

  The spacer 8 may be a long product extending in the longitudinal direction, or a plurality of divided short products may be used. However, when the short spacer 8 is disposed, a portion where the pressure plate 5 and the spacer 8 are only partially in contact with each other is generated, so that a desired plate thickness may not be obtained due to the bending of the pressure plate 5. Therefore, it is desirable to design the arrangement interval of the spacers 8 and the rigidity of the pressure plate 5 in consideration of the amount of bending.

  The thickness of the spacer 8 preferably corresponds to the thickness of the target molded product. Moreover, in order to reduce the thickness of the reinforcing fiber laminate 2 surely in the thinning step described later, it is preferable that the thickness of the reinforcing fiber laminate 2 before vacuum suction is smaller.

  The case where the spacer 8 is used as a single unit has been described so far. However, as shown in FIG. 2, it is also possible to use an integrated pressure plate 21 in which the spacer 8 and the pressure plate 5 are integrated. It is. The advantage of the integrated pressure plate 21 is that when the fiber reinforced plastic is removed from the mold, only the integrated pressure plate 21 needs to be removed first, and the removal work can be facilitated.

  Next, the bagging process will be described. In the bagging process, the sealing material 7 is disposed around the female die 1, the whole of the female die 1 is covered with the bagging material 6, and the sealing material 7 is sealed. The position at which the sealing material 7 is arranged is particularly limited as long as it covers at least the reinforcing fiber laminate 2 and the pressure plate 5 arranged in the above-described process and the suction port 9 provided in the female mold 1. is not.

  The inside between the bagging material 6 and the female mold 1 is vacuum-sucked by the vacuum pump 66 through the suction port 9 of the female mold 1. The sealing material 7 is not particularly limited as long as the vacuum state in the bagging material 6 can be maintained, but is preferably selected in consideration of the heating temperature at the time of molding and compatibility with the matrix resin.

  The bagging material 6 is preferably selected from the resin resistance to be applied and the gas permeability, heat resistance temperature, humidity, etc., which serve as an index for maintaining airtightness. For example, nylon or polyolefin film is preferably used.

  Next, the thinning process will be described. In the thinning step, the vacuum fiber 66 continues to be vacuumed to adsorb the reinforcing fiber laminate 2 to the inner surface of the female mold 1 and the gap between the laminated reinforcing fiber sheet materials or the sheet shape. The space between the reinforcing fibers inside the material is evacuated to reduce the plate thickness of the reinforcing fiber laminate 2, and the spacer 8 and the pressure plate 5 are brought into contact with each other. At this time, auxiliary materials such as the resin diffusion medium 4 and the peel ply 3 may be sandwiched between the spacer 8 and the pressure plate 5.

  Here, “contact” not only refers to a state in which the spacer 8 and the pressure plate 5 are in direct contact with each other, but also the distance between the spacer 8 and the pressure plate 5 becomes substantially constant via the auxiliary material. State is also included. Further, when the integrated pressure plate 21 is used, it is sufficient that the female mold 1 and the integrated pressure plate 21 are “abutted” as described above.

  When the reinforcing fiber laminate 2 is vacuum-sucked, the peripheral length at the corner portion 12 changes as the thickness is reduced, so that the height of the end portion of the reinforcing fiber laminate 2 near the spacer 8 changes. When vacuum suction is performed without the spacer 8 being arranged, the flange 11 and the corner portion 12 are thinned almost uniformly immediately after the start of vacuum suction, but the pressure plate 5 gradually decreases as the thickness of the flange 11 gradually decreases. As a result of the pressing force, the end of the reinforcing fiber laminate 2 is pressed against the female die 1 as if it were fixed to the female die 1. As a result, even if the vacuum suction is continued, it becomes impossible to follow the change in the circumferential length due to the thinning of the corner portion 12, that is, the change in the height of the flange 11 of the reinforcing fiber laminate 2, and the reinforcing fiber laminate pressed against the pressure plate 5 There is a possibility that a non-uniform plate thickness distribution in which only the vicinity of the end of the body 2 is thinned may result.

  In order to eliminate such uneven plate thickness distribution, if a spacer 8 corresponding to a predetermined plate thickness is provided in advance as shown in FIG. 4, the end portion of the reinforcing fiber laminate 2 is excessively thinned. However, the portion where the spacer 8 and the pressure plate 5 abut each other becomes a fulcrum 41 and the thinning process is continued, and the reinforcing fiber having a uniform thickness distribution including the corner portion 12 as shown in FIG. A laminate 2 is obtained. The spacer 8 is fixed to the female die 1 with a magnet as described above or the reinforcing fiber laminate 2 as described above so that the end of the reinforcing fiber laminate 2 is not excessively thinned after the pressure plate 5 comes into contact. It is preferable that the flange 11 is light enough to follow the change in the height of the flange 11 and does not apply unnecessary pressure to the end of the flange 11. Further, the height of the spacer 8 that allows the change in the plate thickness of the web 13 so that the end of the pressure plate 5 does not separate from the spacer 8 following the change in the plate thickness of the web 13 of the reinforcing fiber laminate 2 (see FIG. Preferably, it has a height H in FIG.

  Next, a preferable molding method for using the present invention will be described.

  When the reinforced fiber laminate 2 obtained through the above steps is a prepreg, the matrix resin is impregnated in advance, so the entire female mold is placed in an autoclave and cured by heating and pressure to obtain a molded product. . When the reinforcing fiber laminate 2 is a dry substrate, the matrix resin is impregnated and then the entire female mold is heated to cure the matrix resin.

  When the matrix resin is impregnated with the dry base material, it is preferable to provide the injection port 10 for injecting the matrix resin 62 into the female mold 1. The inlet 10 can be provided at various locations such as the edge of the female mold 1, the edge of the reinforcing fiber laminate 2, and the pressure plate 5, but the vicinity of the inlet 10 is a reinforcement that constitutes the reinforcing fiber laminate 2. Since the fibers may be disturbed, it is preferably provided at a position away from the reinforcing fiber laminate 2 such as on the female mold 1 or the pressure plate 5.

In addition, after impregnating the matrix resin, it may be heat-cured as it is, but in order to obtain a molded product with high performance (high strength, high elasticity, high rigidity, etc.), the proportion of reinforcing fibers in the molded product ( It is also referred to as fiber volume content, hereinafter referred to as V _f ). The range of _Vf is 45% to 65%, more preferably 55% to 65%. In order to achieve such a high V _f , for example, (a) a method of impregnation in a state where vacuum suction is performed in the bagging step and the pressure of the matrix resin is lower than atmospheric pressure, or (b) matrix resin 62 And the reinforcing fiber laminate 2 is excessively impregnated, and then the injection of the resin is stopped, and thereafter the suction of the matrix resin 62 is continued until the target fiber volume content is reached.

  Furthermore, it is preferable to apply a surface pressure to the entire surface of the reinforcing fiber laminate 2 so that the plate thickness can be maintained to such an extent that the reinforcing fiber laminate 2 does not spring back (thickening) during heat curing. When the reinforcing fiber laminate 2 is a prepreg, it is preferable to use a pressurizable autoclave. In addition, when the dry base material is impregnated with the matrix resin, the vacuum suction is stopped when the desired plate thickness is obtained, and the plate thickness is substantially reduced by continuing to pressurize the differential pressure from the atmospheric pressure. It is preferable to complete the molding while maintaining the same.

Here, a method for calculating V _f will be described. V _f can be calculated by the following calculation formula, and the measurement method conforms to ASTM D 3171-99 (2004). Further, the thickness of the spacer 8 may be designed in consideration of the thickness of the auxiliary material.
V _f (%) = (FAW) × (N) / (ρ) / (t) / 1000
FAW: Reinforcement fiber basis weight (g / m ² )
N: Number of stacked layers (ply)
ρ: Reinforcing fiber density (g / cm ³ )
t: Plate thickness (mm)

The fiber reinforced plastic 39 having a small thickness 42 obtained by the above molding method has a high fiber volume content (V _f ) and a defect such as a part (resin rich part) where the ratio of the resin is partially high. Therefore, it can greatly contribute to weight reduction and can be applied to a large structural member. For example, in the C-shaped cross-section member (spar) 52 that is the wing member 51 of the aircraft of FIG. 7 which is an application example of the present invention, an external force 54 is generated that opens the mouth of the C-shaped cross-section through the outer plate member 53. However, it has sufficient strength and can be suitably used. The application range of the present invention is not limited to this as long as the shape has the corner portion 12.

Example 1
The method for producing the fiber-reinforced plastic of the present invention will be described with reference to FIG. 1, which is a cross-sectional view schematically showing the method.

First, carbon fiber (T800S-24K) is used as a reinforcing fiber in the female mold 1 (material: S45C, shape: length of about 6 m × width of about 0.5 m × height of about 0.3 m, plate thickness of 25 mm) used in the present invention. C-shaped cross section having 32 unidirectional carbon fiber woven base materials (FAW = 190 g / m ² ) using Toray Industries, Inc.) and holding the shape with a thermoplastic resin adhered to the surface of the woven base material Reinforcing fiber laminate 2 which is a preform (length: about 5.5 m × width: about 0.3 × height: about 0.1 m) (plate thickness under atmospheric pressure: 7.5 mm, plate thickness under application of approximately 1 atm) : 6.8 mm).

  Holes with a diameter of 10 mm were formed at the upper end of the flange 11 of the reinforcing fiber laminate 2 at a pitch of 0.3 mm, and spacers 8 (columnar shape with a diameter of 9 mm) were placed in these holes. As for the height of the spacer 8, the spacer 8 arranged on the left flange in FIG. 1 has a ferrite magnet of 2.0 mm and stainless steel (SS400) so as to correspond to the plate thickness of the flange 11 6.4 mm (equivalent to Vf = 56%). ) Spacer 8 with 4.4 mm bonded to the right flange is bonded with ferrite magnet 2.0 mm and stainless steel (SS400) 4.0 mm so as to correspond to the plate thickness 6.0 mm of flange 11. The combined ones were placed respectively. The spacer 8 was fixed to the female mold by a magnetic force and did not fall from the flange 11 of the female mold 1.

  Next, peel ply 3 (manufactured by Richmond, B4444, length of about 5.5 m × about 0.5 m, thickness: 0.05 mm), resin diffusion medium 4 (manufactured by Nippon Netron, TSX400P, thickness: 0.55 mm), Each of the reinforcing fiber laminates 2 is covered with a pressure plate 5 (shape: L-shaped cross section and rectangular cross section, material S45C, L-shaped cross section shape: length of about 1.1 m × width of about 0.05 m × height of about 0 0.1 m: thickness 5 mm, rectangular cross-sectional shape: length of about 1 m × width of about 0.3 m: thickness of 5 mm) were sequentially arranged on the reinforcing fiber laminate 2 in a longitudinal direction. In the peel ply 3 and the resin diffusion medium 4, a hole having a diameter of 13 mm was formed in the upper end portion of the left flange, while no hole was provided in the upper end portion of the right flange. That is, the left flange has no peel ply 3 and the resin diffusion medium 4 between the spacer 8 and the pressure plate 5, and the right flange has the peel ply 3 and the resin diffusion medium 4 in between.

  Next, the sealing material 7 is adhered to the outside of the groove corresponding to the suction port 9 and the injection port 10 provided at the upper end of the female mold 1, and the reinforcing fiber laminate 2, peel ply 3, resin diffusion medium 4, pressure plate 5. Was covered with a bagging material 6 (manufactured by Airtech, WL6400) and fixed with a sealing material 7. An injection path 61, a suction path 64, a resin trap 65, and an on-off valve 63 are sequentially connected to the groove serving as the suction port 9, and a vacuum pump 66 is connected to the end of the suction path 64 so that the bagging material 6 and the female mold 1 are connected. The internal space (cavity) was vacuumed. At this time, the opening / closing valve 63 was closed on the injection path 61 side and the suction path 64 side. In addition, all metal materials arranged in the cavity have been subjected to mold release treatment.

  Here, in order to grasp the surface pressure acting on the reinforcing fiber laminate 2, the atmospheric pressure and the degree of vacuum in the cavity on this day were measured. The atmospheric pressure was about 101.4 kPa (= 761 mmHg) using a commercially available barometer. The degree of vacuum in the cavity was about 0.27 kPa (= 2.0 torr) when a leak tester was attached to the end of the injection path 61 and the open / close valve 63 connected to the injection path 61 was opened. It was assumed that a pressure of about 101.1 kPa (= 759 mmHg) was acting on the reinforcing fiber laminate 2.

  Here, when the plate thickness of the reinforcing fiber laminate 2 was calculated, 7.5 mm (a set of plate thicknesses such as female molds and auxiliary materials was measured with a micrometer, and the plate thickness and thickness excluding the reinforcing fiber laminate 2 were calculated. It was obtained by subtracting). From this, it was confirmed that the thickness of the reinforcing fiber laminate 2 is thicker than the spacer 8 at the present time.

  In order to measure the change in the thickness of the reinforcing fiber laminate 2, although not shown, a dial gauge (manufactured by Keyence) is reinforced with a cantilevered arm from the magnetic stand on the female die 1. Two locations were arranged in the height direction of the flange 11 of the laminate 2 (upper flange height: 70 mm from the web surface, lower flange height: 30 mm from the web surface), and one location in the center of the web 13.

  Next, although not shown in the drawings, a heat insulating material is applied to heat and hold the entire female die 1, and a mold temperature controller (KAWATA, TWF-600MD) is attached to the built-in heat medium flow path. The temperature was set to about 80 ° C.

  Confirm that the temperature of the female mold 1 and the reinforcing fiber laminate 2 is within 80 ± 5 ° C., and a resin pot 67 containing the matrix resin 62 (defoamed two-component mixed epoxy resin, 80 ± 10 ° C.). , And arranged so as to be slightly higher than the bottom of the resin pot 67 with respect to the end of the injection path 61. The on-off valve 63 attached to the injection path 61 is slightly opened and held for about 1 minute with the matrix resin 62 guided to just below the on-off valve 63. After about 1 minute, the on-off valve 63 attached to the injection path 61 is retained. Was completely opened, and matrix resin 62 was injected into the cavity. After 30 minutes from the start of injection, the on-off valve 63 connected to the injection path 61 was closed. Thereafter, the on-off valve 63 connected to the suction path 64 is opened for 60 minutes to suck the excess matrix resin 62 impregnated in the reinforcing fiber laminate 2 and to apply pressure to the reinforcing fiber laminate 2 to thereby increase the plate thickness. Reduced.

  When the thickness change was observed with the dial gauge while the thickness was reduced, the change in the dial gauge mounted on the flange height (decrease in the thickness of the reinforced fiber laminate) was the flange height for the first 10 minutes. Although it was larger than the bottom, when 15 minutes passed, the change amount of the dial gauge attached below the flange height exceeded the change amount on the flange height. From this result, it was inferred that the gap 16 at the upper end became almost zero within 15 minutes after the plate thickness was reduced.

  Next, all the on-off valves 63 were closed, the set temperature of the mold temperature controller was raised to 130 ° C., and the matrix resin 62 impregnated in the reinforcing fiber laminate 2 was cured. Then, after cooling to normal temperature (about 30 degreeC), the fiber reinforced plastic 39 was demolded.

When the plate thickness 43 at the upper end of the flange of the fiber reinforced plastic 39 obtained, the plate thickness 44 near the corner, and the thickness of the web were measured at 10 points using a micrometer with a double-sided sphere, the plate thickness at the upper end of the flange was measured. The average value of 43 is 6.00 mm (corresponding to V _f = 56.3%), the average value of the plate thickness 44 near the corner is 6.05 mm (corresponding to V _f = 55.8%), and the average thickness of the web The value was 6.02 mm (corresponding to V _f = 56.1%). The variation in V _f obtained from the result of measuring the total thickness of the flange was 0.2%. Similarly, the V _f variation of the obtained web was 0.3%. From these measurement results, a fiber reinforced plastic with small variations in plate thickness and _Vf was obtained.

(Example 2)
Next, an integrated pressure plate 21 integrated with a spacer as shown in FIG. 2 was used. At this time, the portion corresponding to the spacer is positioned above the flange 11 of the reinforcing fiber laminate 2, and other configurations and processes are the same as in the embodiment except that the drilling performed in the first embodiment is not performed. 1 to produce a fiber reinforced plastic 39.

When the plate thickness 43 at the upper end of the flange and the plate thickness 44 near the corner of the obtained fiber reinforced plastic 39 were measured using a double-sided sphere micrometer, the average value of the plate thickness 43 at the upper end of the flange was 6.05 mm. (V _f = 55.8% equivalent), the average value of the plate thickness 44 near the corner is 5.99 mm (V _f = 56.4% equivalent), and the average value of the web thickness is 6.00 mm (V _f = 56.3% equivalent). The variation in V _f obtained from the result of measuring the total thickness of the flange was 0.3%. Similarly, the V _f variation of the obtained web was 0.2%. From these measurement results, a fiber reinforced plastic having a small variation (standard deviation) in plate thickness and _Vf was obtained.

Example 3
In the same female mold 1 as in Example 1, a unidirectional carbon fiber woven fabric substrate (FAW: 190 g / m ² , T800S-24K (manufactured by Toray)) is impregnated with a resin (3900-2B) as a reinforcing fiber laminate. 32 unidirectional prepregs were stacked and retained in the form of a C-shaped cross-section preform (length approximately 5.5 m × width approximately 0.3 × height approximately 0.1 m, plate thickness under atmospheric pressure: 6.3 mm) The plate thickness under application of approximately 1 atm: 6.2 mm). As in Example 1, after the spacers 8 and the like were arranged and vacuum suctioned, the plate thickness was calculated in the same manner as in Example 1. As a result, the plate thickness of the reinforcing fiber laminate 2 was 6.2 mm.

Then, for the fiber reinforced plastic 39 obtained by autoclave molding, the plate thickness 43 at the upper end of the flange, the plate thickness 44 near the corner and the plate thickness of the web were measured at 10 points using a double-sided sphere micrometer. The average value of the plate thickness 43 at the upper end of the flange is 6.00 mm (equivalent to V _f = 56.3%), the average value of the plate thickness 44 near the corner is 5.85 mm (equivalent to V _f = 57.7%), The average value of the web thickness was 5.90 mm (corresponding to V _f = 57.2%). The variation in V _f obtained from the result of measuring the total thickness of the flange was 0.5%. Similarly, the _Vf variation (standard deviation) of the web obtained was 0.3%. From these measurement results, a fiber reinforced plastic with small variations in plate thickness and _Vf was obtained.

(Comparative Example 1)
As shown in FIG. 6, a fiber reinforced plastic 39 was molded using the same configuration and process as in Example 1 except that the spacer 8 was not disposed.

When the plate thickness 43 at the upper end of the flange of the fiber reinforced plastic 39 obtained, the plate thickness 44 near the corner, and the thickness of the web were measured at 10 points using a micrometer with a double-sided sphere, the plate thickness at the upper end of the flange was measured. The average value of 43 is 5.53 mm (corresponding to V _f = 61.0%), the average value of the plate thickness 44 near the corner is 6.65 mm (corresponding to V _f = 50.8%), and the average thickness of the web The value was 6.04 mm (corresponding to V _f = 55.9%). The variation in V _f obtained from the result of measuring the total thickness of the flange was 1.4%. Similarly, the V _f variation (standard deviation) of the obtained web was 0.2%. From these measurement results, a fiber reinforced plastic having a large variation in both the plate thickness and _Vf was obtained.

DESCRIPTION OF SYMBOLS 1 Female type | mold 2 Reinforcement fiber laminated body 3 Peel ply 4 Resin diffusion medium 5 Pressure plate 6 Bagging material 7 Sealing material 8 Spacer 9 Suction port 10 Inlet 11 Flange 12 Corner part 13 Web 14 Seam interval 15 Seam 16 Upper end part Gap 21 Integrated pressure plate 39 Fiber reinforced plastic 41 Support point 42 Thickness of variation 43 Thickness of flange top 44 Thickness near corner 51 Blade member 52 C-shaped cross section member 53 Outer plate member 54 External force 61 Injection path 62 Matrix Resin 63 On-off valve 64 Suction path 65 Resin trap 66 Vacuum pump 67 Resin pot 70 Preform

Claims (7)

A method for producing a fiber reinforced plastic comprising curing a matrix resin impregnated in a reinforcing fiber laminate having a corner portion, the method comprising at least the following steps.
(A) Reinforcing fiber laminate arrangement step of arranging the reinforcing fiber laminate in a female mold having a corner portion (b) Pressure plate arrangement in which a pressure plate is arranged at least in the corner portion on the reinforcing fiber laminate. Step (c) Spacer arrangement step of arranging a spacer in the gap between the female die and the pressure plate at the end of the pressure plate (d) A sealing material is arranged on the periphery of the female die, and the whole is covered with a bagging material Bagging step (e) While vacuum suctioning the inside of the bagging material, the reinforcing fiber laminate is adsorbed to the female mold, and the reinforcing fiber laminate is thinned so that the spacer and the pressure plate are in contact with each other. Thinning process A method for producing a fiber reinforced plastic comprising curing a matrix resin impregnated in a reinforcing fiber laminate having a corner portion, the method comprising at least the following steps.
(A) Reinforcing fiber laminate placement step of placing the reinforcing fiber laminate in a female mold having a corner portion (b) Pressure with spacer having a spacer on at least one end on the reinforcing fiber laminate (C) a bagging step in which a sealing material is arranged on the periphery of the female mold and the whole is covered with a bagging material; and (d) vacuum-suctioning the inside of the bagging material while laminating the reinforcing fibers. A thinning step of thinning the reinforcing fiber laminate so that the body is adsorbed on the female die and the spacer is in contact with the surface of the female die The thickness of the spacer is produced how a fiber reinforced plastic as claimed in claim 1 or 2, wherein the thinner than the thickness of the laminate in the reinforcing-fiber layered arranging step. In the bagging step, one or a plurality of injection ports for injecting the matrix resin are provided, and in the thinning step, the matrix resin is injected into the reinforcing fiber laminate. The manufacturing method of the fiber reinforced plastic of description. The method for producing a fiber reinforced plastic according to claim 4, wherein after injection of the matrix resin, at least one of the injection ports is switched to a vacuum suction port, and a part of the impregnated matrix resin is sucked. The method for producing fiber-reinforced plastic according to any one of claims 1 to 5, wherein the resin fluidized layer is disposed on substantially the entire surface of the reinforcing fiber laminate not in contact with the female mold surface. The method for producing a fiber reinforced plastic according to claim 1, wherein the fiber reinforced plastic has at least a C cross section.

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