KR102300526B1 - Hybrid composite fiber material, manufacturing method thereof, and aircraft wing structure including the same - Google Patents

Abstract

A method for manufacturing a hybrid composite fiber material according to an embodiment may comprise the following steps of: preparing a fiber fabric layer in which a resin is impregnated; laminating a mesh layer to the fiber fabric layer; laminating a prepreg on the mesh layer; installing a vacuum bag on the fiber fabric layer on which the prepreg is laminated; and injecting a resin into the vacuum bag.

Description

HYBRID COMPOSITE FIBER MATERIAL, MANUFACTURING METHOD THEREOF, AND AIRCRAFT WING STRUCTURE INCLUDING THE SAME

The following description relates to a hybrid composite fiber material, a manufacturing method, and an aircraft wing structure including the same.

The recently developed aircraft airframe structure uses a fiber-reinforced composite material with high specific stiffness/strength as the main material. Fiber-reinforced composite materials can efficiently design the stacking direction of fibers according to the applied load, which enables weight reduction compared to designs using isotropic metal materials. Composite fiber materials are composed of reinforcing fibers that support the main load and resins that hold the fibers, and can be developed with various molding processes depending on how the fibers and resins are applied and cured.

In general, the composite material molding method is an infusion process method in which a preform is made using a reinforcing fiber fabric and a liquid resin is injected into the preform and cured, and a prepreg is used to laminate and in an oven or autoclave. A curing prepreg process has existed.

In the injection process method, as shown in FIG. 1 , a fabric woven with reinforcing fibers is laminated, the structure is bagged using a vacuum bag, and a liquid resin is injected and impregnated/cured. In this process, a flow mesh may be applied, which facilitates the flow of the liquid resin, thereby increasing the impregnation rate and improving the porosity.

In the injection process method, various types of structures can be manufactured depending on the preform production, but it takes a considerable amount of time to produce medium/large structures due to the resin injection time, and there is a possibility that unimpregnated areas may occur when resin is injected into a 3D structure. Because of the height, the injection process method was often applied to the production of secondary structures rather than the main structures that mainly support the load.

The prepreg process method has the advantage that the molding process is relatively simple because semi-hardened resin is applied to the reinforcing fiber, so the curing process is possible after performing only the lamination process without separately injecting the resin. There were disadvantages in that the cost of manufacturing a prepreg for this purpose was expensive and it was difficult to manufacture a structure of a complex shape using the prepreg.

In order to take advantage of the injection process method and the prepreg process method at the same time, as shown in FIG. 2, some structures are laminated using a prepreg to which a semi-cured resin is applied, and the other structures are laminated using a woven fabric. Thereafter, a process method of injecting liquid resin after bagging using a vacuum bag may be devised.

However, in the process of injecting the liquid resin, there is a problem that the impregnation rate of the resin is significantly lowered in the area where the prepreg and the laminated fabric are in surface contact, and a lot of pores may be generated in the surface contact area of the prepreg and the fabric. problems may arise. On the other hand, in order to increase the impregnation rate of the resin, a flow mesh can be applied as shown in Fig. 1, but since the surface contact area of the prepreg-fabric is the joint of the structure, when the flow mesh made of general plastic is applied, the strength of the joint is lowered. Disadvantages exist.

The above-mentioned background art is possessed or acquired by the inventor in the process of derivation of the present invention, and cannot necessarily be said to be a known technology disclosed to the general public prior to the filing of the present invention.

An object of one embodiment is to provide a hybrid composite fiber material, a manufacturing method, and an aircraft wing structure comprising the same.

A hybrid composite fiber material manufacturing method according to an embodiment comprises the steps of: preparing a fiber fabric layer to be impregnated with a resin; laminating a mesh layer to the fibrous fabric layer; laminating a prepreg on the mesh layer; installing a vacuum bag on the prepreg laminated fiber fabric layer; and injecting a resin into the vacuum bag.

The mesh layer may have a mesh structure having a lower density than the fiber fabric layer.

The mesh layer may have a mesh structure made of a glass fiber material.

The mesh layer may be silane treated on the surface of the mesh structure.

The prepreg may have a vertically bent structure after protruding upward in a state of being in surface contact with the mesh layer.

The prepreg may include: a contact portion in surface contact with the mesh layer; a protrusion formed to protrude upward from the contact portion; and an exposed portion supported on the protrusion and facing the contact portion in a parallel state.

The prepreg may have a “C”-shaped cross section in which the contact portion, the protrusion portion, and the exposed portion are bent perpendicular to each other.

The stacking of the prepregs may include disposing a plurality of prepregs spaced apart along a set interval along a direction in which the prepregs are bent.

In the injecting of the resin, the resin may be injected into the vacuum bag along a direction in which the plurality of prepregs are spaced apart.

The composite fiber material according to an embodiment may be manufactured by integrally forming the prepreg and the fiber fabric layer through the hybrid composite fiber material manufacturing method described above.

The wing structure of the aircraft according to an embodiment may include a composite fiber material manufactured by integrally forming the prepreg and the fiber fabric layer through the hybrid composite fiber material manufacturing method described above; and a skin layer laminated on the prepreg of the composite fiber material.

According to the method for manufacturing a hybrid composite fiber material according to an embodiment, when the injection process method and the prepreg method are simultaneously applied in the process of molding the fiber-reinforced composite material, the liquid resin caused by the contact surface between the prepreg and the fiber fabric layer The discontinuity of the flow can be improved.

According to the method for manufacturing a hybrid composite fiber material according to an embodiment, since the fiber fabric layer and the prepreg can be simultaneously cured in a bonded state, the fiber fabric layer and the prepreg can be integrally formed, and the thickness of the joint can be uniformly It can be adjusted to produce a composite fiber material with excellent stiffness/strength and uniform quality.

1 is a diagram schematically illustrating a process for manufacturing a composite fiber material using a conventional injection process.
2 is a diagram schematically illustrating a process of manufacturing a composite fiber material by applying a prepreg to a conventional injection process.
3 is a flowchart of a method for manufacturing a hybrid composite fiber material according to an embodiment.
4 is a diagram schematically illustrating a manufacturing process of a hybrid composite fiber material according to an embodiment.
5 is a view comparing images of a cross-section of a composite fiber material manufactured through a conventional process and a cross-section of a composite material manufactured through a manufacturing method according to an embodiment.
6 is a diagram illustrating a structure including a hybrid composite fiber material according to an embodiment.
7 is a view illustrating a wing structure of an aircraft including a hybrid composite fiber material according to an embodiment.

Hereinafter, embodiments will be described in detail with reference to exemplary drawings. In adding reference numerals to the components of each drawing, it should be noted that the same components are given the same reference numerals as much as possible even though they are indicated on different drawings. In addition, in the description of the embodiment, if it is determined that a detailed description of a related known configuration or function interferes with the understanding of the embodiment, the detailed description thereof will be omitted.

In addition, in describing the components of the embodiment, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only for distinguishing the components from other components, and the essence, order, or order of the components are not limited by the terms. When it is described that a component is “connected”, “coupled” or “connected” to another component, the component may be directly connected or connected to the other component, but between each component another component It will be understood that may also be "connected", "coupled" or "connected".

Components included in one embodiment and components having a common function will be described using the same names in other embodiments. Unless otherwise stated, a description described in one embodiment may be applied to another embodiment, and a detailed description in the overlapping range will be omitted.

3 is a flowchart of a method for manufacturing a hybrid composite fiber material according to an embodiment, FIG. 4 is a diagram schematically illustrating a manufacturing process of a hybrid composite fiber material according to an embodiment, and FIG. 5 is a manufacturing method through a conventional process It is a view comparing each image of the cross-section of the composite fiber material and the cross-section of the composite material manufactured through the manufacturing method according to an embodiment.

3 to 5 , in the method for manufacturing a hybrid composite fiber material according to an embodiment, a prepreg 23 to which a semi-cured resin is applied and some structures are formed by mixing an injection process method and a prepreg process method It is a hybrid process method for producing a composite fiber material 2 in which the fiber fabric layer 21 is integrally formed.

A hybrid composite fiber material manufacturing method according to an embodiment includes the steps of preparing a fiber fabric layer to be impregnated with a resin (11), laminating a mesh layer on the fiber fabric layer (21) (12), and a mesh layer ( 22) of laminating a prepreg (13), installing a vacuum bag on the textile fabric layer 21 on which the prepreg 23 is installed (14), and injecting a resin into the vacuum bag (24). Step 15 may be included.

In the step 11 of preparing the fiber fabric layer, the fiber fabric layer 21 to be impregnated by injecting a liquid resin may be disposed in a layered form.

In step 12 of laminating the mesh layer, a mesh layer 22 having a mesh structure may be laminated on the fibrous fabric layer 21 . For example, mesh layer 22 may be less dense than fibrous fabric layer 21 . For example, the mesh layer 22 may be less thick than the fibrous fabric layer 21 . For example, mesh layer 22 may have a thickness of about 0.2 mm or less.

For example, the mesh layer 22 may be formed of a glass fiber material. For example, in the mesh layer 22 , the surface of the mesh structure may be silane-treated so that the liquid resin can be well impregnated therein in the step 15 of injecting the resin.

According to the mesh layer 22 including glass fibers, in the process of injecting the liquid resin in the step 15 of injecting the resin into the vacuum bag 24, the liquid resin causes the prepreg 23 and the fiber fabric layer. It is possible to induce the liquid resin to be more effectively impregnated between the contact surfaces between (21), so that the decrease in the impregnation rate of the resin in the corresponding contact surface portion can be alleviated.

In addition, as the mesh layer 22 is used, when the flow mesh of the conventional polymer material shown in FIG. 1 is used, the strength of the joint between the fiber fabric layer 21 and the prepreg 23 is reduced. can do.

In the step 13 of laminating the prepreg, a prepreg 23 formed in advance and having a semi-cured resin applied thereto may be laminated on the mesh layer 22 .

For example, the prepreg 23 may have a vertically bent structure after protruding upward in a state in which it is in surface contact with the mesh layer 22 .

For example, the prepreg 23 may have a plurality of configurations, in which case the plurality of prepregs 23 may be disposed on the mesh layer 22 spaced apart from each other.

For example, the prepreg 23 includes a contact portion 231 that is in surface contact with the mesh layer 22 , a protrusion 232 protruding upwardly from the contact portion 231 , and supported on the protrusion 232 , It may include an exposed portion 233 facing in parallel to the contact portion 231 .

For example, the exposed portion 233 and the contact portion 231 may form ends facing each of upper and lower sides of the protrusion 232 . For example, the exposed portion 233 and the contact portion 231 may have a shape bent in a direction parallel to the surfaces of the textile fabric layer 21 and the mesh layer 22 with respect to the protrusion 232 .

For example, the prepreg 23 may have a cross-sectional shape bent in a 'C' shape as shown in FIG. 4 . In other words, the prepreg 23 may have a structure of a contact portion 231 and an exposed portion 233 that are vertically bent in the same direction at upper and lower sides of the protrusion 232 .

Step 14 of installing the vacuum bag may be a process of installing the vacuum bag 24 after the prepreg 23 is laminated on the mesh layer 22 .

The vacuum bag 24 may be installed to seal the fiber fabric layer 21 and the prepreg 23 that are in surface contact with each other through the mesh layer 22 from the outside.

For example, the vacuum bag 24 communicates with the inside of the vacuum bag 24 to have a resin inlet 241 through which liquid resin is injected, and a resin outlet through which the liquid resin injected into the vacuum bag 24 is discharged ( 242) may be included.

For example, the resin inlet 241 and the resin outlet 242 may be respectively installed at opposite ends of the fiber fabric layer 21 among the parts of the vacuum bag 24 . Accordingly, the direction in which the liquid resin is injected into the vacuum bag 24 and flows may be determined according to the positional relationship between the resin inlet 241 and the resin outlet 242 .

For example, after the fiber fabric layer 21 on which the prepreg 23 is laminated is bagged to the vacuum bag 24 , negative pressure is applied to the inside of the vacuum bag 24 to make the inside of the vacuum bag 24 . It can be placed in a vacuum.

The step of injecting the resin 15 may be a process of injecting a liquid resin into the vacuum bag 24 and impregnating the resin injected into the fiber fabric layer 21 and the mesh layer 22 with the resin. .

In the step of injecting the resin 15 , the liquid resin is injected through the resin injection hole 241 so that the liquid resin can flow along the planes of the fiber fabric layer 21 and the mesh layer 22 .

For example, the direction in which the liquid resin is injected into the vacuum bag 24 and flows may be the same as the direction in which the plurality of prepregs 23 are spaced apart from each other.

For example, the direction in which the liquid resin is injected into the vacuum bag 24 and flows is parallel to the direction in which the upper and lower ends of the prepreg 23 are bent in a direction parallel to the plane of the fiber fabric layer 21 . can For example, a direction in which a liquid resin is injected into the vacuum bag 24 and flows may be parallel to a direction in which the contact portion 231 is bent with respect to the protrusion 232 .

Referring to FIG. 5 , an image of a cross-section of the adhesive part to which the mesh layer 22 is not applied and a cross-section of the adhesive part to which the mesh layer 22 is applied can be identified. Specifically, Fig. 5 (a) shows a cross-section of the bonding surface between the prepreg and the fiber fabric layer of the conventional composite fiber material shown in Fig. 2, Fig. 5 (b) is a composite fiber material according to an embodiment A cross-section of the bonding surface between the fibrous fabric layer 21 and the prepreg 23 of the composite fiber material 2 produced through the manufacturing method is shown.

Comparing the two images of FIG. 5 , it can be confirmed that many pores are generated on the surface and inside in the case of the bonding surface of the conventional composite fiber material of FIG. 5 ( a ), whereas the embodiment of FIG. In the case of the bonding surface of the composite fiber material 2 according to , it can be seen that almost no pores exist on the surface and inside.

According to the hybrid composite fiber material manufacturing method according to an embodiment, in the process of molding the fiber-reinforced composite material, the injection process method and the prepreg method are simultaneously applied, between the prepreg 23 and the fiber fabric layer 21 . It is possible to improve the discontinuity of the flow of the liquid resin caused by the contact surface.

According to the hybrid composite fiber material manufacturing method according to an embodiment, since the fiber fabric layer 21 and the prepreg 23 can be simultaneously cured in a bonded state, the fiber fabric layer 21 and the prepreg 23 are integrally formed. It can be molded into a composite fiber material (2) with excellent rigidity/strength and uniform quality because the thickness of the joint can be uniformly controlled.

6 is a diagram illustrating a structure including a hybrid composite fiber material according to an embodiment.

Referring to FIG. 6 , a composite fiber material structure 3 including a composite fiber material 2 according to an exemplary embodiment may be identified.

The composite fiber material structure 3 includes a composite fiber material 2 produced through the hybrid composite fiber material manufacturing method shown in FIGS. 3 to 5 and an outer skin layer 31 bonding to the other side of the composite fiber material 2 . may include.

As shown in FIG. 6 , the composite fiber material 2 formed by integrally forming the fiber fabric layer 21 and the prepreg 23 forms one side of the structure 3 , and the outer skin layer 31 is The other side of the structure 3 may be formed by combining it to be supported on the protruding prepreg 23 .

According to the structure of the composite fiber material structure 3 according to an embodiment, the fiber fabric layer 21 and the outer skin layer 31 facing each other have a shell structure exposed in opposite directions and have a predetermined thickness. structures can be formed.

7 is a view illustrating a wing structure of an aircraft including a hybrid composite fiber material according to an embodiment.

Referring to FIG. 7 , the configuration of the wing structure 42 of the aircraft 4 including the composite fiber material 2 according to an embodiment can be confirmed.

The wing structure 42 may include a composite fiber material 2 produced through the method for manufacturing a composite fiber material shown in FIGS. can

As shown in FIG. 6 , the composite fiber material 2 formed by integrally forming the fiber fabric layer 21 and the prepreg 23 forms one side of the wing structure 42 , and the outer skin layer 31 . The other side of the wing structure 42 may be formed by combining it to be supported on the protruding prepreg 23 .

The wing structure 42 according to an embodiment has a shell structure in which the textile fabric layer 21 and the shell layer 31 facing each other are exposed in opposite directions, respectively, and the prepreg 23 is formed therebetween. spar).

According to the wing structure 42 including the composite fiber material 2 according to an embodiment, the fabric layer 21 and the prepreg 23 are integrally molded to form the composite fiber material 2 having excellent strength of the adhesive part. As it is used, not only can excellent strength/rigidity be expected, but also the wing structure 42 can be formed only through bonding between the pre-adhesive composite fiber material 2 and the outer skin layer 31, so assembly/ There is an advantage that the attachment process can be simplified.

As described above, although the embodiments have been described with reference to the limited drawings, various modifications and variations are possible from the above description by those of ordinary skill in the art. For example, the described techniques are performed in an order different from the described method, and/or the described components of structures, devices, etc. are combined or combined in a different form than the described method, or other components or equivalents are used. Appropriate results can be achieved even if substituted or substituted by

Claims (11)

preparing a fibrous fabric layer to be impregnated with a resin;
laminating a mesh layer to the fibrous fabric layer;
laminating a prepreg on the mesh layer;
installing a vacuum bag on the prepreg laminated fiber fabric layer; and
Including; injecting a liquid resin into the vacuum bag;
The mesh layer has a mesh structure of a glass fiber material having a lower density than the fiber fabric layer,
In the step of injecting the resin, the liquid resin is impregnated into the fiber fabric layer and the mesh layer, and the prepreg is cured while being integrally bonded to the fiber fabric layer. manufacturing method.
delete delete The method of claim 1,
The mesh layer is a hybrid composite fiber material manufacturing method, characterized in that the surface of the mesh structure is silane-treated.
The method of claim 1,
The prepreg is a hybrid composite fiber material manufacturing method, characterized in that it has a vertically bent structure after protruding upward in a state of being in surface contact with the mesh layer.
6. The method of claim 5,
The prepreg is
a contact portion in surface contact with the mesh layer;
a protrusion formed to protrude upward from the contact part; and
and an exposed portion supported on the protrusion and facing in parallel with the contact portion.
7. The method of claim 6,
The prepreg is a hybrid composite fiber material manufacturing method, characterized in that the contact portion, the protrusion portion and the exposed portion have a "U" cross section bent perpendicular to each other.
7. The method of claim 6,
The step of laminating the prepreg,
and disposing a plurality of prepregs spaced apart along a set interval along a direction in which the prepregs are bent.
9. The method of claim 8,
The step of injecting the resin,
Method for producing a hybrid composite fiber material, characterized in that the resin is injected into the vacuum bag along a direction in which the plurality of prepregs are spaced apart.
A composite fiber material manufactured by integrally forming the prepreg and the fiber fabric layer through the hybrid composite fiber material manufacturing method according to claim 1 .
In the wing structure of the aircraft,
a composite fiber material manufactured by integrally forming the prepreg and the fiber fabric layer through the hybrid composite fiber material manufacturing method according to claim 1; and
and a skin layer laminated on the prepreg of the composite fiber material.

Images