JP2010137527A - Repairing method for composite material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a repairing method for composite materials, by which repairs can be performed even when other members are present around a damaged section, or the shape of the surface of a mother material around the damaged section is not one flat surface, but is a complicated one. <P>SOLUTION: A prepreg is laminated and arranged at the damaged section of a composite material in a manner to form a tapered section 6 on two counter side surfaces. The tapered section keeps a dummy member 24 arranged on the top to form a flat surface with the surface of the dummy member and that of the laminated prepreg. Then, a heater mat 12 which can heat the total surface is arranged in a manner to cover the dummy member and the laminated prepreg. The total surface of the heater mat is coated with a coating material to turn a space formed between the coating material and the composite material vacuumized. Then, after curing the laminated prepreg by heating the total surface of the heater mat, the dummy member is removed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for repairing a composite material, and in particular, a method for repairing a composite material capable of repairing even a complicated shape portion such as the presence of another member in the vicinity of a corner R portion or in the vicinity of a damaged portion. It is about.

  Conventionally, plastic has been widely used as a lightweight material. However, although plastic is lightweight, it has a low elastic modulus and is not suitable as a structural material. Therefore, when used as a structural material, fibers with a high elastic modulus are kept in the plastic with orientation. It is used as fiber reinforced plastic (FRP) that is light and strong. As the fiber having a high elastic modulus, for example, carbon fiber or glass fiber is used. In particular, FRP (Carbon Fiber Reinforced Plastics: CFRP) using carbon fiber as a reinforcing fiber is higher in strength and elastic modulus than other FRPs. Because of its high corrosion resistance and excellent corrosion resistance, it is widely used in various fields such as aircraft, space equipment, automobiles, and railways.

  In such FRP parts, there are cases where defective parts or damaged parts are formed, such as bubbles generated inside during manufacture or scratches when assembling a structure using the FPR parts. If a defective part or a damaged part is generated, the strength of the FRP component is reduced, and thus repair is required.

A conventional method for repairing a damaged portion of an FRP component will be described with reference to FIG.
FIG. 7 is an explanatory view of a conventional method for repairing a damaged portion of an FRP component.
First, the damaged portion 104 formed on the base material 102 of the FRP component is included, and the periphery of the damaged portion 104 is removed by grinding. At this time, if the damaged portion 104 and its periphery are deleted so that only the damaged portion is covered, the deleted portion becomes a shape perpendicular to the surface of the base material 102, and stress concentration occurs in the deleted portion. A constant slope 106 of the grinding part to be provided is provided.

Next, a repair patch 108 made of a prepreg in which an adhesive film and a fiber reinforcing material are impregnated with an uncured thermosetting resin is disposed in the grinding portion.
After the repair patch 108 is disposed, the thermocouple 110 is installed on the surface of the base material 102 around the repair patch 108, and the heater mat 112 is installed so as to cover the entire repair patch 108.

Thereafter, a back film 116 is installed so as to cover the entire heater mat 112, and a space formed between the back film 116 and the base material 102 and including the repair patch 108, the thermocouple 110, and the heater mat 112 is drawn by the suction device 114. Apply vacuum.
Further, while monitoring the temperature of the thermocouple 110 and controlling the temperature, heat is applied from the heater mat 112 to the repair patch 108 to equalize the temperature, and the repair patch 108 is cured and bonded to the base material 102.

  As described above, for example, Patent Document 1 discloses an FRP repair method in which a damaged portion and its periphery are deleted, a repair patch is disposed on the deleted portion, the repair patch is cured and bonded to a base material. Yes.

USP 6,761,783

  However, as described with reference to FIG. 7, the FRP repair method in which the damaged portion and its periphery are deleted, the repair patch is disposed on the deleted portion, and the repair patch is cured and bonded to the base material is the periphery of the damaged portion. If the surface of the base material is flat, the damaged part can be repaired without any problem, but there are other parts around the damaged part, or the shape of the base material surface around the damaged part is not flat. Is difficult to apply.

  For example, as shown in FIG. 8, when the other member 120 exists in the vicinity of the damaged portion 104 formed on the base material 102, the periphery A of the damaged portion 104 is not affected by the other member 120. It is difficult to grind with a shape having a certain angle, and it is difficult to repair the damaged portion 104.

  For example, as shown in FIG. 9, even when there is a complicated shape portion such as the corner R narrow portion 122 in the vicinity of the damaged portion 104 formed in the base material 102, there is a periphery B around the damaged portion 104. It is difficult to grind with a shape having a certain angle, and repair of the damaged portion 104 is difficult.

  Therefore, in view of the problems of the prior art, the present invention performs repair even when there are other members around the damaged part or the shape of the base material surface around the damaged part is not a flat surface but a complicated shape. An object of the present invention is to provide a method for repairing a composite material that can be used.

  In order to solve the above problems, in the present invention, a prepreg in which a fiber reinforcing material is impregnated with an uncured thermosetting resin in a damaged portion of a composite material formed by reinforcing fibers by placing them in a plastic is used. In the method of repairing a composite material in which the prepreg is cured by arranging and heating to repair the damaged portion, the prepreg is laminated so as to form tapered portions on two opposite side surfaces of the damaged portion of the composite material A dummy member is arranged on the tapered portion, a plane is formed by the dummy member and the surface of the laminated prepreg, and the entire surface is heated so as to cover the dummy member and the laminated prepreg. A possible heater mat, covering the entire surface of the heater mat with a covering material, evacuating a space formed between the covering material and the composite material, By heating, after curing the prepreg the laminated, characterized in that removing the dummy member.

As a result, the damaged part is not ground, and the prepreg is laminated and disposed on the damaged part.Therefore, there are other members around the damaged part, and the shape of the surface of the base material around the damaged part is not flat but complicated. Even a simple shape can be repaired.
Furthermore, by arranging the prepregs so as to produce a tapered portion on two opposing side surfaces, stress concentration is prevented from occurring at the end of the laminated prepreg (hereinafter, the laminated prepreg is referred to as a repair patch). be able to.
Further, a dummy member is disposed on the tapered portion at the end of the repair patch, and the dummy member, the repair patch, and the heater mat are made flat by making the surface of the dummy member and the repair patch, that is, the surface in contact with the heater mat, flat. There is almost no gap between them. Therefore, it can be evacuated to a uniform pressure and heated to a uniform temperature. Accordingly, it is possible to prevent a defective quality of the repair patch due to non-uniform pressure and a defective curing of the repair patch due to non-uniform temperature.

  Therefore, even if there are other members around the damaged part or the surface of the base material around the damaged part has a complicated shape, it can be repaired with good quality, and the application range of the composite material repair is expanded.

  Also, an auxiliary member having the same thickness as the laminated prepreg (repair patch) and having heat resistance to the heating temperature of the heater mat is juxtaposed with the laminated prepreg, and the prepreg laminated with the dummy member; The surface of the heater mat facing the heater mat is made larger than the area of the heater mat facing the laminated prepreg.

The heater mat usually has a heating wire such as a nichrome wire embedded therein, and the heater mat must be newly purchased to change its size and shape. Therefore, when the area of the surface facing the repair patch of the heater mat is larger than the area of the surface facing the heat mat of the repair patch without using the auxiliary member, the portion that cannot contact the repair patch or the dummy member The heater mat may be deformed, but by using the auxiliary member, the entire surface of the heater mat can come into contact with the repair patch, dummy member or auxiliary member, thereby preventing the heater mat from being deformed. be able to. As a result, the repair can be performed with good quality, and the versatility of the heater mat is enhanced.
In addition, the said auxiliary member needs to have heat resistance with respect to the heating temperature of a heater mat, For example, the thing made from a silicon rubber sheet or a fluororesin can be used.

Further, the prepreg is laminated in such a manner that a side end portion is in contact with the surface of the composite material.
Thereby, the repair patch without the level | step difference by a prepreg in the said taper part can be created.

In addition, a member having heat resistance with respect to the heating temperature of the heater mat is disposed on the tapered portion, and then the dummy member is disposed on the member.
Thereby, the dummy member can be easily removed. As the member, for example, a film sheet made of fluorinated ethylene propylene (FEEP) can be used. Moreover, silicone oil which is heat resistant oil can also be apply | coated not on a film sheet but on a taper part.

  As described above, according to the present invention, it is possible to perform repair even if there are other members around the damaged portion or the shape of the surface of the base material around the damaged portion is not a flat surface but a complicated shape. A method of repairing a composite material can be provided.

  Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention unless otherwise specified, but are merely illustrative examples. Not too much.

Example 1 is an example of the repair method of the said damaged part in case the corner R part exists in the vicinity of the damaged part formed in the base material of FRP components.
FIG. 2 is a perspective view of the periphery of the damaged portion in the first embodiment. In FIG. 2, reference numeral 2 denotes a base material of the FRP component. The base material 2 is provided with a corner R portion 22, and a damaged portion 4 is formed on the surface of the base material near the corner R portion 22.

  FIG. 1 is a flowchart illustrating a procedure for repairing a composite material according to the first embodiment. A procedure for repairing the damaged portion 4 formed on the base material 2 of the FRP component in FIG. 2 will be described with reference to FIG.

When the repair is started, a repair patch is formed on the damaged portion in step S1.
The formation of the repair patch will be described with reference to FIGS. 3 is a view in the direction of arrow C in FIG.
The repair patch 8 is formed so as to cover the damaged portion 4 as shown in FIG.
The repair patch 8 is formed by laminating a plurality of prepregs 18 as shown in FIG. End portions of the respective prepregs 18 are in contact with the surface of the base material 2, and inclined portions 6 are provided on two side surfaces of the repair patch 8.
By forming the repair patch 8 by laminating the prepreg 18 so that the inclined portions 6 are formed on the two opposing side surfaces, it is possible to prevent stress concentration from occurring at the end of the repair patch 8.

When the formation of the repair patch 8 is completed in step S1, a dummy composite material is placed in step S2.
As the dummy composite material 24, for example, a composite material formed by laminating the same prepreg as that for forming the repair patch 8 can be used.

The arrangement of the dummy composite material 24 will be described with reference to FIG. FIG. 4 is an enlarged view of a portion D in FIG. In FIG. 4, the base material 2 is not shown.
As shown in FIG. 4, the dummy composite material 24 is disposed on the inclined portion 6 in the repair patch 8.
As will be described later, since the dummy composite material 24 is removed later, in order to facilitate the removal, the heat resistance against the heating temperature by the heater mat described later is provided between the inclined portion 6 and the dummy composite material 24. A thin member (film, coating film, etc.) having Examples of the member having heat resistance with respect to the heating temperature by the heater mat include an FEP film and a silicone oil coating film.
The dummy composite material 24 is arranged on the inclined portion 6 so that a plane is formed by the surface 26 of the dummy composite material and the surface 28 of the repair patch.

When the placement of the dummy composite material 24 is completed in step S2, a heater mat is placed in step S3.
The arrangement of the heater mat 12 will be described with reference to FIG.
As shown in FIG. 4, the L-shaped heat mat 12 is used, and the L-shaped heat mat 12 is installed so as to cover the entire surface of the dummy composite material surface 26 and the repair patch surface 28. . As described in step S2, since the plane is formed by the surface 26 of the dummy composite material and the surface 28 of the repair patch, between the heat mat 12 and the surface 26 of the dummy composite material and the surface 28 of the repair patch. There is almost no gap.
Further, a thermocouple 10 is disposed on the surface of the base material 2 in the vicinity of the repair patch 8.

When the arrangement of the heater mat is completed in step S3, evacuation is performed in step S4.
The evacuation will be described with reference to FIG.
FIG. 5 is a view taken in the direction of arrow E in FIG. However, although the illustration of the base material 2 is omitted in FIG. 4, the base material 2 is also shown in FIG. 5, and the back film 16 described later shows a cross section.

First, the back film 16 is installed so as to cover the entire heater mat 12. Next, a space formed between the back film 16 and the base material 2 and including the repair patch 8, the dummy composite material 24, the thermocouple 10, and the heater mat 12 is evacuated by the suction device 14.
As described above, there is almost no gap between the heat mat 12 and the surface 26 of the dummy composite material and the surface 28 of the repair patch. It is possible to prevent the repair patch from being lost due to the above.

When evacuation is completed in step S4, heating is performed in step S5.
The heating is performed while maintaining the evacuation state performed in step S4, the temperature of the thermocouple 10 is monitored and the temperature is controlled, and heat is applied from the heater mat 12 to the repair patch 8 to equalize and repair. The patch 108 is cured and adhered to the base material 2.
As described above, there is almost no gap between the heat mat 12 and the surface 26 of the dummy composite material and the surface 28 of the repair patch, so that it is possible to prevent the repair patch from being defectively cured due to uneven temperature. Can do.

  When heating is completed in step S5, the evacuation by the suction device 14 is stopped in step S6, the back film 16 and the heater mat 12 are sequentially removed, and then the dummy composite material 24 is removed. Since the FEP film or the like is disposed between the dummy composite material 24 and the inclined portion 6 of the repair patch 8, the dummy composite material 24 can be easily removed.

By performing the operations in the above steps S1 to S6, even if the surface of the base material around the damaged portion has a complicated shape, it can be repaired with good quality. Accordingly, the application range of the composite material is expanded.
In the first embodiment, an example in which a damaged portion is present in the vicinity of the corner R portion shape has been described. However, the present invention can also be applied to cases in which a damaged portion is present in the vicinity of another complicated shape.

FIG. 6 is a perspective view of the periphery of the repair patch end portion in the second embodiment.
In FIG. 6, the same reference numerals as those in FIGS.

  In FIG. 6, a heater mat 12b is used in which the area of the surface facing the plane is larger than the area of the plane formed by the surface 26 of the dummy composite material and the surface 28 of the repair patch.

The auxiliary member 32 is arranged so as to be arranged in parallel with the repair patch 8. The auxiliary member 32 uses a silicon rubber sheet, but other members can be substituted if the auxiliary member 32 is formed of a member having heat resistance with respect to the heating temperature by the heater mat 12b.
Further, the auxiliary member 32 has the same thickness as that of the repair patch 8, so that a plane is formed by the surface 26 of the dummy composite material, the surface 28 of the repair patch, and the surface 30 of the auxiliary member. At this time, the auxiliary surface is formed so that the area of the plane formed by the surface 26 of the dummy composite material, the surface 28 of the repair patch, and the surface 32 of the auxiliary member is equal to or larger than the area of the surface of the heater mat 12b facing the plane. The size of the member 30 is selected.

  The heater mat 12b normally has a heating wire such as a nichrome wire embedded therein, and the heater mat 12b must be newly purchased to change its size and shape. Therefore, when the heater mat 12b is used without using the auxiliary member 32, a portion that cannot contact either the dummy composite material surface 26 or the repair patch surface 28 of the heater mat 12b is generated and deformed at the portion. However, by using the auxiliary member 32, the entire surface of the heater mat 12 b facing the repair patch 8 is the surface of the dummy composite material surface 26, the repair patch surface 28, or the auxiliary member surface 32. Since it can contact either, the deformation | transformation of the heater mat 12b can be prevented. As a result, the repair can be performed with good quality, and a larger heater mat may be prepared, and the versatility of the heater mat 12b is enhanced.

  Even if there is another member around the damaged part or the shape of the surface of the base material around the damaged part is not a flat surface but a complicated shape, it can be used as a repair method for a composite material that can be repaired.

3 is a flowchart illustrating a procedure for repairing a composite material according to the first embodiment. FIG. 3 is a perspective view around a damaged portion in the first embodiment. It is a C direction arrow directional view in FIG. It is the D section enlarged view in FIG. It is an E direction arrow directional view in FIG. FIG. 10 is a perspective view of the periphery of a repair patch end in Example 2. It is explanatory drawing of the repair method of the damaged part of the conventional FRP component. It is explanatory drawing of the example from which the repair method of the damaged part of the conventional FRP component becomes difficult. It is explanatory drawing of another example from which the repair method of the damaged part of the conventional FRP component becomes difficult.

Explanation of symbols

2 Base material (composite material)
4 Damaged part 6 Inclined part (tapered part)
8 Repair patch (Laminated prepreg)
12, 12b Heater mat 16 Back film (coating material)
18 Prepreg 22 Corner R part 24 Dummy composite material (dummy member)
32 Auxiliary members

Claims (4)

Place the prepreg impregnated with uncured thermosetting resin in the fiber reinforcing material in the damaged part of the composite material formed by reinforcing the fiber by putting it in plastic and heat the thermosetting In the method of repairing the composite material, which cures the damaged part by curing the resin,
Laminating the prepreg so as to form a tapered portion on two opposing side surfaces in the damaged portion of the composite material,
A dummy member is arranged on the tapered portion, and a plane is formed by the dummy member and the surface of the laminated prepreg,
A heater mat capable of heating the entire surface is disposed so as to cover the dummy member and the laminated prepreg,
The entire surface of the heater mat is covered with a covering material, and a space formed between the covering material and the composite material is evacuated,
A method for repairing a composite material, comprising: heating the entire surface of the heater mat to cure the laminated prepreg, and then removing the dummy member. An auxiliary member having the same thickness as the laminated prepreg and having heat resistance to the heating temperature of the heater mat is juxtaposed with the laminated prepreg,
The prepreg laminated with the dummy member and the auxiliary member, and the area of the surface facing the heater mat,
2. The method for repairing a composite material according to claim 1, wherein an area of a surface of the heater mat facing the laminated prepreg is made larger.   The method for repairing a composite material according to claim 1 or 2, wherein the prepreg is laminated such that a side end portion thereof is in contact with a surface of the composite material.   4. The dummy member is disposed on the member after disposing a member having heat resistance with respect to the heating temperature of the heater mat on the tapered portion. Repair method for composite materials.

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