JP2010120167A - Method of manufacturing preform and fiber reinforced plastic - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for bringing a reinforced fiber base material into close contact with a shaping mold having rugged parts at side faces to shape the reinforced fiber base material into a mold shape without a crease. <P>SOLUTION: This method of manufacturing a preform obtained by bringing a reinforced fiber laminate into close contact with a male mold having recesses and projections at the side faces, includes at least steps of disposing the reinforced fiber laminate on the male mold, disposing rubber on the reinforced fiber laminate and decompressing a space sealed with the rubber. In the decompressing step, when applying pressure to the reinforced fiber laminate sequentially from the upper face to the side faces through the rubber, external force is applied from the outside of the rubber along the recesses of the side faces. Pressure is thereby applied to the recesses sequentially from the shoulder parts to the side faces of the reinforced fiber laminate, and then pressure is sequentially applied from the upper face to the side faces of the reinforced fiber laminate by the rubber. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a manufacturing method of a preform used for obtaining a girder having a complicated shape, particularly for a structural member such as a transportation device made of fiber reinforced plastic, and fiber reinforcement using the preform obtained by the method. The present invention relates to a plastic manufacturing method.

  In recent years, the transportation equipment industry has been required to improve fuel efficiency in response to soaring crude oil fuel. In the aircraft industry in particular, there is a strong demand from airlines because fuel efficiency is directly linked to running costs. In order to reduce the weight of aircraft in each aircraft manufacturer, fiber reinforced plastics with excellent specific rigidity and specific strength (especially, Application of carbon fiber reinforced plastics is underway.

  The fiber reinforced plastic member is made of a fabric made of glass fiber, carbon fiber, polyamide fiber or the like as a reinforcing fiber and a resin material. The fabric is pre-impregnated with a matrix resin in advance, and a dry base into which the matrix resin is injected later. There are materials, etc., and each is obtained by degassing or impregnating resin while heating and pressurizing in an autoclave, oven or the like, and curing and integrating the matrix resin.

  In the case of a structural member used for transportation equipment or the like, the fiber reinforced plastic obtained by the molding method as described above has many complicated shapes as represented by the C-type cross section spar for aircraft, Technology called shaping is important. When shaping with a metal material, it can be machined, but fiber reinforced plastics are directly connected to the reduction in rigidity and strength, so machining cannot be applied easily, and a reinforced fiber substrate can be applied to a complex mold. It is necessary to mold along.

  There are various problems in shaping reinforcing fibers along a complex mold. For example, the fibers do not fit well in the concave portion of the mold, and a gap may be formed between the concave portion and the reinforcing fiber, and a desired shape may not be obtained. Further, when force is applied to the reinforcing fiber along the mold, the fiber may be bent or the orientation angle may be deviated, and desired physical properties may not be obtained.

  In order to solve the problems as described above, Patent Document 1 describes a composite material sheet processing apparatus, but this apparatus is intended for impregnating a reinforcing fiber base material with a resin and laminating a plurality of them. Therefore, there is a description that it is difficult to obtain a large shape by vacuum suction, and it is difficult to prevent wrinkles from occurring.

  Moreover, in patent document 2, after pressing the substantially center part of the fiber base material arrange | positioned on a shaping type | mold, it is fiber by using the method of pressing continuously in the direction separated from a center part to an edge part. A method for suppressing bridging is described. However, this method does not describe the countermeasures when the development view of the geometric type is different from that of the fiber base material, and there is only a method of notching the fiber base material. It is a manufacturing method that is unlikely to have a structural member in mind because it causes a decrease in strength.

Further, Patent Document 3 describes a method of manufacturing a preform having a flat part and a plurality of bead parts protruding from the flat part and arranged in a predetermined direction. In this method, when the reinforcing fiber base material is covered with rubber and the weight is further arranged from above, the reinforcing fiber base material is sequentially placed away from the central portion, and then the inside of the rubber is decompressed to form the reinforcing fiber base material into a shaping mold. Although it adheres, it is possible to arrange a weight for the flat portion, and it does not correspond to the case where there is a bulge on the side surface.
JP 2006-335049 A (0003, 0010 1-3 lines) JP 2006-188791 A (Claim 1, 0022 1-2 lines) JP 2008-230019 (Claim 1)

  Therefore, the present invention solves such a conventional problem, and in particular, the reinforcing fiber base material is closely attached to a shaping mold having a concavo-convex portion on the side surface, and the reinforcing fiber base material is applied to the shaping mold shape without any defects. The object is to provide a method for producing a preform obtained by shaping.

The present invention for solving this problem has the following configuration. That is,
1. A method of manufacturing a preform obtained by closely attaching a reinforcing fiber laminate to a male mold having irregularities on at least side surfaces, the step of arranging the reinforcing fiber laminate on the male mold, and the reinforcing fiber laminate A step of disposing rubber from above and a step of decompressing the space sealed with the rubber, and in the step of depressurizing, the reinforcing fiber laminate is sequentially pressed from the upper surface to the side surface through the rubber. When applying, an external force is applied from the outside of the rubber along the concave portion of the side surface, so that the concave portion is sequentially pressed from the shoulder portion to the side surface of the reinforcing fiber laminate, and then the reinforcing fiber is applied by the rubber. A method for producing a preform, wherein a pressing force is sequentially applied from the upper surface to the side surface of the laminate.

  2. 1. When pressing pressure is applied to the concave portion on the side surface, pressing pressure is also applied to the side surface facing the concave portion. The preform production method according to 1.

  3. The reinforcing fiber laminate is composed of a dry substrate. Or 2. A process for producing the preform as described in 1.

  4). 2. A resin material is applied to at least one surface of the dry substrate, and the layers of the dry substrate are integrated by heating the reinforcing fiber laminate and softening the resin material. A process for producing the preform as described in 1.

  5. 3. After heating the reinforcing fiber laminate, the resin material is solidified by cooling. A process for producing the preform as described in 1.

  6.1. ~ 5. A method for producing a fiber reinforced plastic, comprising a step of injecting and impregnating a liquid resin into the preform according to any one of the above, and then curing the resin.

  Since the present invention employs a method in which a reinforcing fiber laminate is closely adhered to a male mold having a complex shape in order to produce a girder member having a complex shape, a fiber-reinforced plastic having a high strength expression rate can be obtained. The desired preform that can be obtained is obtained.

  As a result of intensive studies, the inventors of the present invention closely attached the reinforcing fiber laminate 20 to the male mold 5 having irregularities on the side surfaces in order to manufacture the above-mentioned problem, that is, a girder having a complicated shape without defects such as wrinkles. The present inventors have found a method for producing a preform obtained through the step of causing the preform to be obtained. The shape to which this method can be applied (here, particularly the cross-sectional shape) can be applied to the C-shaped cross section 1, the L-shaped cross section 2, the hat-shaped cross section 3, the Z-shaped cross section 4 and the like as shown in FIG. The shape is not limited as long as the shape can be produced using the male mold 5 having unevenness on the side surface.

  First, the reason why wrinkles 36 and bridging 35 are generated in the reinforcing fiber laminate 20 constituting the preform 6 having unevenness on the side surface obtained by using the male mold 5 having unevenness on the side surface in FIG. 3, will be described. FIG. 2 shows a three-dimensional shape as an example of the male mold 5 having irregularities on the side surface on the left side, and a cross-sectional view showing the A cross section on the right side. The configuration of the male mold 5 having irregularities on the side surface can be classified into an upper surface 8, a shoulder portion 9, and a side surface 10 using the A cross section 7, and the side surface 8 of the male mold 5 having irregularities on the side surface is at least 1 There are more than the number of recesses 11 and protrusions 12.

  A male mold having a concave portion 11 and a convex portion 12 on the side surface is shown in FIG. That is, as shown in the male development view 14 obtained by developing using the development portion 13 of the male mold 5 having unevenness on the side surface shown in FIG. An overlap 17 is generated, and a gap 18 is generated on the side surface 10 of the male convex portion 16. Comparing the male development view 14 and the plan view 19 of the reinforcing fiber laminate 20 used in the present invention, the male concave portion 15 lacks the reinforcing fiber laminate 20, and the male die and the convex portion 16 reinforce. The fiber laminate 20 is left over. The male fiber having the male development view 14 including such deficiencies and surpluses is provided with a reinforcing fiber laminate 20 having a gap 46 (see FIGS. 10 and 11) and a heel (slack) 36 (see FIGS. 11 and 12). In order to keep the reinforced fiber laminate 20 in close contact with each other, the reinforced fiber laminate 20 must be brought into close contact with the expansion and contraction (deformation). (See FIGS. 10 and 11). The ridges 36 and bridging 35 generated in the reinforcing fiber laminate 20 do not disappear even if they become a preform, and traces remain even in a molded product obtained by resin-molding the preform. The strength and surface quality are reduced as compared with the case without the ring 35. The wrinkles 36 and the bridging 35 that cause this decrease strongly depend on the geometrical mismatch between the male development view 14 and the reinforcing fiber laminate 20 and the deformability of the reinforcing fiber laminate 20, and in the latter case, for example, The reinforcing fiber laminate 20 made of a prepreg constrained by a resin is likely to generate wrinkles 36, whereas it is difficult to occur in a dry base material not constrained by a resin. The preform manufacturing method of the present invention is a manufacturing method that sufficiently exhibits the deformability of the reinforcing fiber laminate 20, and is preferably applied to a dry substrate having a high deformability.

  The present invention will be described with reference to FIGS. 4 to 9 showing a part of the preform manufacturing process of the present invention. An example of an apparatus configuration used in carrying out the present invention is a tool 24 having a hinge 23 attached to a rubber 22 with a metal frame 21 as shown in FIG. 5, a rubber seal 25 and a vacuum port 26 are provided. This apparatus configuration does not limit the present invention.

  First, as shown in FIG. 5 showing one step of the preform manufacturing method of the present invention, the reinforcing fiber laminate 20 is disposed on the male mold 5 having unevenness on the side surface, and the vacuum line 27 is attached to the vacuum port 26. Next, as shown in FIG. 6, a rubber 22 having the metal frame 21 is placed on a tool 24, and a rubber seal 25 corresponding to a protrusion attached on the tool 24 and the rubber 22 are brought into close contact with each other. A sealed space 28 is formed by the rubber 22 and the rubber seal 25. Here, it is preferable that the tool 24 and the male mold 5 having unevenness on the side surface include a heating mechanism. As the heating mechanism, a heating medium pipe or an electric heater is provided in the tool 24 or the male mold 5. And IH, but are not limited to these as long as they can be heated stably. The material of the rubber seal 25 or the rubber 22 is preferably not permanently deformed by the heating, and specific examples thereof include neoprene, ethylene propylene rubber, silicon rubber, and fluoro rubber. It is not limited to these as long as it can be shaped and used repeatedly.

  Next, when the sealed space 28 formed by the tool 24 and the rubber 22 as shown in FIG. 6 is vacuum-sucked from the vacuum line 27 attached via the vacuum port 26, it is a cross-sectional view on the right side of FIG. As shown in the BB ′ cross section 29, the rubber fiber 22 causes the reinforcing fiber laminate 20 to be in close contact with the lower surface in the order of the upper surface 8, the shoulder portion 9, and the side surface 10 of the male mold 5 having irregularities on the side surface. Specifically, as shown in the BB ′ cross section 29 in FIG. 7, the male mold 5 having unevenness on the side surface and the reinforcing fiber laminate 20 are in close contact with each other, and the movement of the rubber 22 occurs when the force generated by vacuum suction and the rubber tension are balanced. Stops. It is preferable that the contact height 31 of the side surface to be contacted when the movement of the rubber stops is at least as close as the product line 32 on the side surface of the reinforcing fiber laminate 20. Furthermore, considering the form stability and consistency of the preform obtained by shaping the reinforcing fiber laminate 20, it is desirable that the entire surface of the reinforcing fiber laminate 20 is in close contact.

  Here, in the conventional shaping method, the reason why the bridging 35 is caused when the reinforcing fiber laminate 20 is brought into close contact with the concave portion 11 on the side surface of the male mold 5 having irregularities on the side surface is shown in FIG. FIG. 8 which is a diagram (concave portion sectional view 40), FIG. 8 which is a diagram of the concave portion vicinity section 38 (concave portion sectional view A41), and FIG. 10 which shows a C cross section 33 which is a wrinkle occurrence place in the concave portion.

  In the vacuum suction A diagram of FIG. 8, when vacuum suction is performed through the vacuum line 27, the rubber 22 is brought into close contact with the upper surface 8, the shoulder portion 9, and the side surface 10 in order, and the contact height is increased as in vacuum suction A, B, and C. 31 becomes lower. Comparing the contact height 31 between the recess sectional view 40 and the recess vicinity sectional view A41, there is a difference in the sealing height 28 between the vacuum suctions B and C. This difference is partly due to the geometrical deficiency of the rubber 22, and as shown in the male development view 14 of FIG. Thus, a large amount of deformation is required until the male mold 5 having unevenness on the side surface is brought into close contact with, and the force required for the deformation is large, and the rubber 22 in the sectional view of the recess 40 in the drawings of vacuum suction B and C is from the sectional view A41 near the recess. The reinforcing fiber laminate 20 is brought into close contact with the mold 5 having irregularities on the side surfaces with a delay. As a result, the reinforcing fiber laminate 20 in the recess sectional view 40 is restrained from being deformed due to the influence of the reinforcing fiber laminate 20 in the recess vicinity sectional view A41 being restrained, and the bridging 35 is generated. As shown in the male development view 14 of FIG. 3, the difference in the adhesion height that causes the bridging 35 is that the shortage of the reinforcing fiber laminate 20 increases as the distance from the shoulder 9 increases. Thus, the vacuum suction B and C increase in this order.

  When the conventional method 43 of FIG. 10 showing the bridging shape from another cross section will be described, the reinforcing fiber laminate 20 in the cross sectional view B50 in the vicinity of the concave portion has irregularities on the side surface by the rubber pressing force 49 of the rubber 22 in the concave portion 11. Since the reinforcing fiber laminate 20 in the recess 11 cannot be deformed because it is pressed against the male mold 5, a gap 46 is formed between the male mold 5 having irregularities on the side surface and the reinforcing fiber laminate 20, and the bridging 35 is formed. appear.

  Therefore, in the present invention, in order to prevent the mold gap 46 from occurring, FIG. 9 is a view of the recess cross section 37 of FIG. 6 (recess cross section view 40) and a cross section of the recess vicinity 38 (recess vicinity cross sectional view A41). By applying an external force 42 to the reinforcing fiber laminate 20 from the outside of the rubber 22 as in vacuum suction A and B, the contact height 31 of the recess sectional view 40 is kept lower than the contact height 31 of the recess vicinity cross section A41, It restrains that the influence of the restraint by the pressing force applied by the rubber 22 in the recess vicinity section A41 reaches the reinforcing fiber laminate 20 in the recess section view 41.

  As a result, as shown in the present invention 44 in FIG. 10, which corresponds to the sectional view of the C section 33 in FIG. 7 corresponding to the next step in FIG. 6, the reinforcing fiber laminate 20 has the male mold 5 having irregularities on the side surfaces. It is possible to make close contact with the recess 11 without forming the mold gap 46. Further, in the case of the arc-shaped concave portion 5 such as the L-shaped cross section 2, the hat-shaped cross section 3, and the Z-shaped cross section 4 of FIG. In addition, it can be brought into close contact with the arc-shaped recess 5. The timing at which the external force 42 is applied to the rubber 22 is as shown in the schematic cross-sectional view of the present invention in FIG. 9 in consideration of the positional displacement suppression of the reinforcing fiber laminate 20 that may occur when the external force 42 is applied from the outside of the rubber 22. First, in the vacuum suction A, the sealed space 28 formed by the tool 24 and the rubber 22 is vacuum-sucked, and the upper surface 8 and the shoulder 9 of the male mold 5 having irregularities on the side surface are reinforced through the rubber 22. It is preferable to apply a pressing pressure to the fiber laminate 10 and restrain it to some extent. More preferably, as shown in the schematic cross-sectional view of the present invention in FIG. 9, the reinforcing fiber laminate is applied from both sides by applying an external force 42 to the side surface facing the recess 11 of the male mold 5 having irregularities on the side surface. The method of restraining 20 is mentioned. However, the method is not limited thereto as long as it is a method for preventing the positional deviation of the arranged reinforcing fiber laminate 20.

  Further, the position where the external force 42 is applied to the arc-shaped recess 11 such as the L-shaped section 2, the hat-shaped section 3, and the Z-shaped section 4 shown in FIG. It is preferable to add to 51. This is because bridging 35 is frequently generated because the maximum concave portion 51 requires the most deformation, and when an external force 42 is applied to the maximum concave portion 51, it is considered that the bridging suppression effect is also large.

  Next, FIG. 11 which is a cross-sectional view comparing a part of the preform manufacturing method of the present invention and the conventional method, and a cross-sectional view showing the convex portion of the conventional method with respect to the male side shape preferable for application of the present invention This will be described with reference to FIG. In the cross-sectional view of the conventional method 43 in FIG. 11, the reinforcing fiber laminate 20 corresponding to the male recess 11 is insufficient and is restrained by the rubber pressing force 49. Bridging 35 and mold gap 46 are generated. On the other hand, as shown in FIG. Therefore, in the present invention 44 of FIG. 11, the external force 42 is applied to the concave portion 11 before the vicinity of the concave portion 50 is restrained, and the wrinkles (slackness) of the reinforcing fiber laminate 10 generated in the convex portion 12 is moved 47 in the concave direction. By doing so, the bridging 35 can be eliminated and at the same time the heel 36 can be suppressed. However, when the distance between the concave portion 11 and the convex portion 12 is long, the effect is small because the force is not transmitted well, and the distance between the concave portion 11 and the convex portion 12 is preferably close.

  Next, the reinforcing fiber laminate 20 of the present invention is closely attached to the male mold 5 having irregularities on the side surfaces, and in order to maintain the shape, a tacky resin material is applied to the surface of the reinforcing fiber base. In the case where a resin material is applied to the surface of the reinforcing fiber laminate 20, when the resin material is heated with a substantially vacuum pressure applied through the rubber 22 (there is no figure at the time of heating), the resin material Is softened, and the layers of the reinforcing fiber laminate 20 can be integrated. Since the reinforcing fiber laminate 20 in which the resin material is in a softened state lacks shape stability, the reinforcing fiber laminate 20 is once cooled to solidify the resin material, whereby a male mold having irregularities on the side surface. It is desirable to obtain a preform having a shape substantially corresponding to 5. However, when the shaping mold (here, the male mold having irregularities on the side surface) and the molding mold are the same, the molding may be performed without cooling. The preform surface after cooling is not sticky at room temperature to prevent handling and adhesion of foreign matter, and it is preferable that the shape change with time is small, and the resin material is solid (40 ° C. or lower) at room temperature.

  The resin material is preferably composed mainly of a thermoplastic resin that can be repeatedly softened so that it can be repeatedly shaped, for example, polyamide, polysulfone, polyethersulfone, polyetherimide, polyphenylene ether, polyimide, polyamideimide. At least one of phenoxy is preferable, and among these, polyamide, polyetherimide, polyphenylene ether, and polyether sulfone are particularly preferable. In addition, examples of the form of the resin material include fibers, films, and particulates. Among these, particulates are preferable. In the case of particles, it can be sprayed and applied to the surface of the dry base material constituting the reinforcing fiber laminate 20 with a spray or calender roll, and the particle size and the amount of adhered particles can be easily controlled. The particle diameter controlled in this way can control the amount of particles dissolved in the matrix resin when the matrix resin is injected and molded, thereby realizing suitable interlayer physical properties. In addition, the controlled particle adhesion amount is suitable for forming a gap between layers of the reinforcing fiber laminate by appropriately forming the air permeability of the dry base material (a parameter having a correlation with the impregnation property of the matrix resin in the thickness direction) and the reinforcing fiber laminate. It is possible to suitably control the impregnation property of the matrix resin.

  The thermoplastic resin is a main component of particles made of a resin material, and the blending amount of the thermoplastic resin in the resin material is preferably 70 to 100% by weight. More preferably, it is 75-97 weight%, More preferably, it is 80-95 weight%. If the blending amount is less than 70% by weight, it may be difficult to obtain a fiber reinforced plastic excellent in impact resistance. Moreover, when a thermoplastic resin is the main component, the adhesion of the resin material 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.

  The reinforcing fiber laminate 20 obtained by laminating the reinforcing fiber base material (dry base material) provided with the resin material on the surface thereof is handled when the interlayer is partially bonded using the resin material. In this case, fluff, looseness, and stacking angle are unlikely to occur, which is preferable. In addition, when the partial adhesive form is adhered (62) with a spot in the thickness direction over substantially one surface of the reinforcing fiber base material, the deformability characteristic of the dry base material is generally maintained and the handling property is maintained. Is preferable. Moreover, the range of the said spot adhesion 62 is preferable when it does not straddle four or more strands in order not to suppress the deformation | transformation capability of a dry base material more than necessary. However, it is not necessary to apply the adhesive to the portion where the reinforcing fiber laminate 20 needs to undergo large deformation locally, for example, the concave portion 11 and the convex portion 12. In the spot bonding method, the reinforcing fiber laminate 20 is heated by an oven, a hot plate, IH, or the like, and the resin material is softened and spot pressed from above the reinforcing fiber laminate 20, or for spot pressurization. Although the method of integrating the layers of the reinforcing fiber laminate 20 by heating and pressing the indenter 61 against the reinforcing fiber laminate 20 is not particularly limited, an adhesion method using the indenter 61 is included. Is preferable because the adhesive strength can be easily controlled from the indenter material, shape, pitch 64, heating temperature, pressure, heating / pressurization holding time, and the like. By controlling the adhesive strength, the deformability and handling property of the reinforcing fiber laminate 20 can be suitably set.

  In particular, considering the thermal conductivity, the material of the indenter 61 is preferably a metal material. Further, the shape of the indenter 61 is formed with a curve such as a circle or an ellipse, or a shape having a chamfered or rounded head so that the reinforcing fiber is not damaged when surface pressure is applied. It is preferable that The diameter 65 of the circular indenter 61 can be set in consideration of not straddling four or more strands, which is a preferable range of the adhesive 62. For example, if the strand width is 2 mm, the surface pressure can be set within a range where the surface pressure can be applied so that the diameter (long diameter in the case of an elliptical diameter) smaller than 2 mm / 4 × 4 = 8 mm is 3 mm. Next, a preferable heating temperature depends on Tg (glass transition temperature) of the resin material, and is within Tg ± 30 ° C., more preferably within Tg ± 20 ° C., which does not unnecessarily suppress deformation of the dry base material. Moreover, a preferable pressure range is more than 0.01 MPa and 0.4 MPa or less which does not promote the fiber undulation 63 around the spot bonded portion. More preferably, it exceeds 0.05 MPa and is 0.2 MPa or less. Whether the fiber undulation 63 around the bonded portion is significantly promoted is determined by cross-sectional observation (measurement of fiber undulation height, width, radius of curvature, etc.) and compression strength test (SACMA SRM 1R-94). Etc.). A preferable heating / pressurizing holding time is set in consideration of the time required for the reinforcing fiber laminate 20 to reach a desired temperature within ± 5 ° C., and is not less than 0.5 minutes and not more than 10 minutes. The heating / holding time range can be measured by arranging thermocouples in the thickness direction of the reinforcing fiber laminate 20 and in the vicinity of the middle layer and the surface layer corresponding to the application of surface pressure with the indenter 61.

  After injecting and impregnating a liquid resin into the preform 6 having unevenness on the side obtained in the present invention, the resin is cured (in the case of using a thermoplastic resin as the liquid resin, it means cooling and solidification). The molded product (fiber reinforced plastic) having unevenness on the side surface obtained in this manner does not generate bridging 35, so there is no mold gap 46 and the resin richness is extremely small. For this reason, when a repeated stress due to heat or load is applied, a crack that becomes a starting point of fracture hardly occurs, and the fatigue strength can be estimated high. Further, since the ridge 36 (fiber meandering) is small, it is difficult for buckling deformation of the reinforcing fiber when compressive stress is applied, and the expression rate of compressive strength is high. As a result, not only the surface quality but also the design strength can be set high, and the high specific strength and high specific rigidity, which are advantages of the composite material, can be sufficiently exhibited. As the liquid resin, a thermosetting resin is preferably used. Examples of such thermosetting resins include unsaturated polyesters, vinyl esters, epoxies, phenols (resol type), urea melamines, polyimides, bismaleimides and cyanate esters, and their copolymers, modified products and A resin obtained by blending at least two of these can also be used.

  Such a molded product having irregularities on the side surface is required to have mechanical characteristics, for example, a structural member (girder) constituting a main wing or tail wing of an aircraft, a structural member for other transportation equipment, or a structural member for construction It can use suitably for. However, the present invention is a technique that can be widely applied to girders having irregularities on the side surfaces, and is not limited to the scope of application of the above-described example.

Example 1
This will be described with reference to FIGS. 4 to 9 showing a part of the preform manufacturing process of the present invention. As shown in FIG. 4, the apparatus used consists of a tool 24 (SUS, plate thickness 10 mm) in which a metal frame 21 (Al angle material) attached to a rubber 22 is connected via a hinge 23 as shown in FIG. Is a male mold 5 (made of SUS, approximately 4 m in length, 400 mm in width, 100 mm in height, 5 mm in thickness, with a pipe for temperature control inside), rubber seal 25 (silicon with a diameter of 30 mm) A rubber round string is bonded and integrated with a silicon-based adhesive), and a vacuum port 26 (a brass coupler joint is attached to the screw hole in which the tool is tapped from the back surface of the tool 22).

  First, as shown in FIG. 5, the reinforcing fiber laminate 20 was disposed on the male mold 5 having irregularities on the side surfaces, and the vacuum line 27 was attached to the vacuum port 26. The reinforcing fiber laminate 20 is a unidirectional woven fabric substrate obtained by weaving reinforcing fibers made of carbon fibers (Toray: T800S-24K), and has a particulate resin whose main component is a thermoplastic resin on the surface. Material is applied. The particulate resin material applied has Tg = 67 ° C. and a particle size of 200 μm or less. If the reinforcing fiber laminate 20 is heated and pressurized, the layers can be integrated and the form can be maintained. The reinforcing fiber laminate 20 has a metal indenter 61 (diameter 65: Φ 3 mm, pitch 64: 15 mm) heated to 70 ° C., as shown in an embodiment in which the layers of the reinforcing fiber laminate 20 are bonded in FIG. 13. Using the arranged crimping jigs 60, the reinforcing fiber laminate 20 is pressed by applying a load equivalent to 100 kPa per indenter, held for 5 minutes, and then the indenter jig 60 is removed. is there.

  Next, as shown in FIG. 6, the rubber 22 having the metal frame 21 is placed on the tool 24, and the rubber seal 25 attached on the tool 24 and the rubber 22 are brought into close contact with each other, so that the tool 24, the rubber 22, A sealed space 28 is formed by the rubber seal 25.

  In order to vacuum-suck the formed sealed space 28, the valve of the vacuum line 27 was opened. When the vacuum line 27 is opened, as shown in FIG. 9, after the pressure of the rubber 22 is applied to a part of the mold part 9 of the reinforcing fiber laminate 22, as shown in the vacuum suction A of FIG. An external force 42 was applied along the concave portion 11 of the male mold 5 having an uneven portion on the side surface. The external force applied to the recess 11 was applied so that the contact height 31 of the recess did not exceed the contact height 31 of the vicinity 50 of the recess.

  The method of applying the external force 42 used the hand roller 52 as in the present invention in FIG. As a result, bridging 35 and wrinkles 36 did not occur in the concave portion 11 and the convex portion 12 as in the present invention 44 of FIG. Therefore, a mold temperature controller (TWK-600MD manufactured by KAWATA) is connected to the coupler attached to the male pipe through a pressure hose, and the rubber 22 is covered with a heat insulating material (glass wool, about 100 mm). Then, the temperature of the mold temperature controller was set to 80 ° C. which is equal to or higher than the Tg of the resin material, and the reinforcing fiber laminate 20 was held at 80 ± 5 ° C. for 3 hours.

  Thereafter, the mold temperature controller is set to 20 ° C., the preform is cooled, the resin material is solidified, the vacuum line is closed, and the sealed space 28 is opened to the atmosphere to obtain a preform. It was. Bridging 35 and ridges 36 could not be observed in the concave portion 11 and the convex portion 12 of the preform 6 having irregularities on the obtained side surface.

  Next, in order to form the obtained preform into VaRTM, a peel ply (resin release layer), a medium (resin diffusion medium), a pressure plate, a resin injection, and a suction port are provided in the molding female mold to inject the resin. A nylon tube was connected to the suction port. The end of the nylon tube on the resin injection port side was sealed, and the nylon tube on the resin suction port side was connected to the vacuum line 27 via a resin trap. Thereafter, the entire female mold is covered with a bagging film (Richmond, HS-800), the periphery of the female mold and the bagging film are sealed with sealant tape (Richmond, Tacky tape), and the valve of the vacuum line 27 is opened. Vacuum was applied to bring the preform into close contact with the female mold.

  Thereafter, the entire female mold is placed in a drying furnace capable of heating up to 180 ° C., the furnace temperature is set to 80 ° C., and when the entire female mold reaches about 80 ° C. or higher, it is connected to the resin injection port. After clamping the nylon tube with a vise grip, the end of the nylon tube was opened and inserted into a cup (dispo cup, 5 L) filled with a two-pack type epoxy resin.

  The clamp part was gradually opened so that the air was not mixed into the inserted nylon tube, and the epoxy resin was filled up to the clamp part. Then, after 2 minutes, the clamp was opened and resin was injected into the preform. The injection stop of the resin was judged by visually confirming that the injected resin reached the resin suction port, and the nylon tube connected to the resin injection port was clamped with a vise grip. Thereafter, the nylon tube on the resin suction port side is quickly clamped with a vise grip, and the drying furnace is heated to 130 ° C. and held for 3 hours to cure the epoxy resin, and then about 3 to room temperature (about 30 ° C.). Cooled over time. The surface of the molded product obtained by demolding from the female mold, in particular, the resin rich seen when the bridging 35 is formed in the concave portion 11, and the ridge 36 (fiber meander) is present in the convex portion 12. Not observed.

(Comparative Example 1)
This will be described with reference to FIGS. 4 to 9 showing a part of the preform manufacturing process of the present invention. As shown in FIG. 4, the apparatus used consists of a tool 24 (SUS, plate thickness 10 mm) in which a metal frame 21 (Al angle material) attached to a rubber 22 is connected via a hinge 23 as shown in FIG. Is a male mold 5 (made of SUS, approximately 4 m in length, 400 mm in width, 100 mm in height, 5 mm in thickness, with a pipe for temperature control inside), rubber seal 25 (silicon with a diameter of 30 mm) A rubber round string is bonded and integrated with a silicon-based adhesive), and a vacuum port 26 (a brass coupler joint is attached to the screw hole in which the tool is tapped from the back surface of the tool 22).

  First, as shown in FIG. 5, the reinforcing fiber laminate 20 was disposed on the male mold 5 having irregularities on the side surfaces, and the vacuum line 27 was attached to the vacuum port 26. The reinforcing fiber laminate 20 is a unidirectional woven fabric substrate obtained by weaving reinforcing fibers made of carbon fibers (Toray: T800S-24K), and has a particulate resin whose main component is a thermoplastic resin on the surface. Material is applied. The particulate resin material applied has Tg = 67 ° C. and a particle size of 200 μm or less. If the reinforcing fiber laminate 20 is heated and pressurized, the layers can be integrated and the form can be maintained. The reinforcing fiber laminate 20 has a metal indenter 61 (diameter 65: Φ 3 mm, pitch 64: 15 mm) heated to 70 ° C., as shown in an embodiment in which the layers of the reinforcing fiber laminate 20 are bonded in FIG. 13. Using the arranged crimping jigs 60, the reinforcing fiber laminate 20 is pressed by applying a load equivalent to 100 kPa per indenter, held for 5 minutes, and then the indenter jig 60 is removed. is there.

  Next, as shown in FIG. 6, the rubber 22 having the metal frame 21 is placed on the tool 24, and the rubber seal 25 attached on the tool 24 and the rubber 22 are brought into close contact with each other, so that the tool 24, the rubber 22, A sealed space 28 is formed by the rubber seal 25.

  In order to vacuum-suck the formed sealed space 28, the valve of the vacuum line 27 was opened. When the vacuum line 27 is opened, pressure is applied to the upper surface 8, the mold part 9, and a part of the side surface of the reinforcing fiber laminate 20 via the rubber 22 as shown in the right figure of FIG. The shaping was completed in a state where the sealing height 28 of the cross section 37 was higher than the cross section 38 near the recess. As a result, bridging 35 was generated in the concave portion 11 and wrinkles 36 were generated in the convex portion 12 as in the conventional method 43 of FIG.

  In order to heat the reinforcing fiber laminate in which wrinkles are generated, a mold temperature controller (TWK-600MD manufactured by KAWATA) is connected to the coupler attached to the male pipe via a pressure hose, and the rubber 22 It is covered with a heat insulating material (glass wool, about 100 mm) from above, the temperature of the mold temperature controller is set to 80 ° C. which is equal to or higher than the Tg of the resin material, and the reinforcing fiber laminate 20 is 3 at 80 ± 5 ° C. Held for hours.

  Thereafter, the mold temperature controller is set to 20 ° C., the preform is cooled, the resin material is solidified, the vacuum line is closed, and the sealed space 28 is opened to the atmosphere to obtain a preform. It was. Bridging 35 and wrinkles 36 were observed on the concave portions 11 and the convex portions 12 of the preform 6 having irregularities on the obtained side surfaces.

  Next, a peel ply (resin release layer), a medium (resin diffusion medium), a pressure plate, a resin injection, and a suction port are provided in a molding die for VaRTM molding of the obtained preform. A nylon tube was connected to the injection and suction ports. The end of the nylon tube on the resin injection port side was sealed, and the nylon tube on the resin suction port side was connected to the vacuum line 27 via a resin trap. Thereafter, the entire female mold is covered with a bagging film (Richmond, HS-800), the periphery of the female mold and the bagging film are sealed with sealant tape (Richmond, Tacky tape), and the valve of the vacuum line 27 is opened. Vacuum was applied to bring the preform into close contact with the female mold.

  Thereafter, the entire female mold is placed in a drying furnace capable of heating up to 180 ° C., the furnace temperature is set to 80 ° C., and when the entire female mold reaches about 80 ° C. or higher, it is connected to the resin injection port. After clamping the nylon tube with a vise grip, the end of the nylon tube was opened and inserted into a cup (dispo cup, 5 L) filled with a two-pack type epoxy resin.

  The clamp part was gradually opened so that the air was not mixed into the inserted nylon tube, and the epoxy resin was filled up to the clamp part. Then, after 2 minutes, the clamp was opened and resin was injected into the preform. The injection stop of the resin was judged by visually confirming that the injected resin reached the resin suction port, and the nylon tube connected to the resin injection port was clamped with a vise grip. Thereafter, the nylon tube on the resin suction port side is quickly clamped with a vise grip, and the drying furnace is heated to 130 ° C. and held for 3 hours to cure the epoxy resin, and then about 3 to room temperature (about 30 ° C.). Cooled over time. The surface of the molded product obtained by demolding from the female mold, in particular, the recess 11 had traces of bridging 35 and was resin-rich. Moreover, the plate | board thickness of the convex part 12 was thick. Therefore, when the cross section of the thick part was cut and observed, a large meandering was observed in the layer.

This figure schematically illustrates the shape of the preform of the present invention. This figure schematically illustrates the configuration of the mold of the present invention. This figure schematically illustrates a development view of the mold of the present invention and a plan view of the reinforcing fiber laminate. This figure schematically illustrates the manufacturing apparatus of the preform manufacturing method of the present invention. This figure schematically illustrates a part of the preform manufacturing process of the present invention. This figure schematically illustrates a part of the preform manufacturing process of the present invention. This figure schematically illustrates a part of the preform manufacturing process of the present invention. This figure schematically illustrates a part of a preform manufacturing process sectional view of a comparative example. This figure schematically illustrates a part of the preform manufacturing process sectional view of the present invention. This figure schematically illustrates a part of a sectional view of a preform manufacturing process comparing the present invention with a comparative example. This figure schematically illustrates a part of a sectional view of a preform manufacturing process comparing the present invention with a comparative example. This figure schematically illustrates a part of a preform manufacturing process sectional view of a comparative example. This figure schematically illustrates a method for producing a reinforced fiber laminate according to the present invention and one embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 C type cross section 2 L type cross section 3 Hat type cross section 4 Z type cross section 5 Male mold 6 which has unevenness on the side surface 7 Preform having unevenness on the side surface A Across section 8 14 Male mold development 15 Male concave part 16 Male convex part 17 Overlap 18 Clearance 19 Plan view of reinforcing fiber laminate 20 Reinforcing fiber laminate 21 Metal frame 22 Rubber 23 Hinge 24 Tool 25 Rubber seal 26 Vacuum port 27 Vacuum Line 28 Sealed space 29 BB 'cross section 30 Side downward 31 Sealed height 32 Product line 33 C cross section 34 D cross section 35 Bridging 36 皺 (slack)
37 Concave section 38 Concave section 39 Convex section 40 Concave section 41 Concave section A
42 External force 43 Conventional method 44 The present invention 45 Male mold 46 Mold gap 47 The heel moves toward the concave portion 48 Maximum concave portion 49 Rubber pressing force 50 Near the concave portion 51 Maximum concave portion 52 Hand roller 60 Indenter jig 61 Indenter 62 Spot adhesion 63 Around the adhesion portion Fiber swell 64 pitch 65 diameter

Claims (6)

A method of manufacturing a preform obtained by closely attaching a reinforcing fiber laminate to a male mold having irregularities on at least side surfaces, the step of arranging the reinforcing fiber laminate on the male mold, and the reinforcing fiber laminate A step of disposing rubber from above and a step of decompressing the space sealed with the rubber, and in the step of depressurizing, the reinforcing fiber laminate is sequentially pressed from the upper surface to the side surface through the rubber. When applying, an external force is applied from the outside of the rubber along the concave portion of the side surface, so that the concave portion is sequentially pressed from the shoulder portion to the side surface of the reinforcing fiber laminate, and then the reinforcing fiber is applied by the rubber. A method for producing a preform, wherein a pressing force is sequentially applied from the upper surface to the side surface of the laminate. The preform manufacturing method according to claim 1, wherein when a pressing pressure is applied to the concave portion on the side surface, the pressing pressure is also applied to the side surface facing the concave portion. The method for producing a preform according to claim 1 or 2, wherein the reinforcing fiber laminate is composed of a dry base material. The resin material is provided to at least one side surface of the dry base material, and the layers of the dry base material are integrated by heating the reinforcing fiber laminate to soften the resin material. A process for producing the preform as described in 1. The preform manufacturing method according to claim 4, wherein after heating the reinforcing fiber laminate, the resin material is solidified by cooling. A method for producing a fiber-reinforced plastic, comprising a step of curing the resin after injecting and impregnating the liquid resin into the preform according to claim 1.

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