Composite material wedge forming method

Abstract

The invention relates to a composite material wedge forming method, and belongs to the field of composite material manufacturing. The invention relates to a composite material wedge forming method, which comprises the following steps of: (1) manufacturing a semi-split type pressure equalizing plate by using a wedge pressure equalizing plate forming mold; (2) carbon fiber prepreg is laid on the wedge forming mold to be manufactured into a part prefabricated body, and the semi-split type pressure equalizing plate and the part prefabricated body are assembled and packaged; (3) transferring an assembly body of the semi-split type pressure equalizing plate and the part prefabricated body to an autoclave for curing and forming; and (4) processing and finishing the shape of the cured part by using a shape inspection mold and a shape inspection template. The method has the following advantages that the manufacturing cost is reduced, the manufacturing period is shortened, the production efficiency is improved, and the shape accuracy of the sharp corner of the wedge is ensured.

Description

Technical Field

[0001] The present invention relates to a method for forming a composite wedge, belonging to the field of composite material manufacturing. Background Art

[0002] Wedge parts are widely used in the outer end faces of aircraft components and have an assembly relationship with the pneumatic housing parts, so high requirements are imposed on their outer shapes, especially the outer shape of the tip of the parts. The outer shape of a certain type of composite wedge is similar to a "saddle", and its top is a sharp-corner structure. The forming of the sharp corner is a manufacturing difficulty for such parts. Generally, there are two traditional methods for forming wedges. One is to use a rubber core mold in cooperation with a female mold. This method requires the prior production of a transition mold and then the production of a rubber core mold. Due to the complex surface of such parts, after the parts are formed, it is easy to have the situation of sharp-corner glue accumulation or blunt sharp corners. In response to this situation, the sharp corners of the parts are generally repaired and formed using room-temperature glue + short fibers. The above method is not only difficult to operate but also increases the manufacturing process, undoubtedly reducing the production efficiency and making it difficult to ensure the outer shape quality of the sharp corners of the parts. The other is to use an integral equalizing plate in cooperation with a male mold. In the process of using this method, it is easy to have the phenomenon that the equalizing plate and the part preform cannot be fully matched, resulting in difficulties in forming the sharp corners of the parts and ultimately affecting the delivery progress of the parts. Summary of the Invention

[0003] The purpose of the present invention is to provide a method for forming a composite wedge with a conforming outer shape by using a special-structured equalizing plate in combination with a male mold.

[0004] To achieve the above purpose, the present invention adopts the following technical solutions: A method for forming a composite wedge, comprising the following steps: (1) Using a wedge equalizing plate forming mold to make a semi-split equalizing plate; (2) Laying carbon fiber prepreg on the wedge forming mold to make a part preform, and assembling and packing the semi-split equalizing plate and the part preform; (3) Transferring the assembly of the semi-split equalizing plate and the part preform to a autoclave for curing and forming; (4) Using an outer shape inspection mold and an outer shape inspection template to process and trim the outer shape of the cured part.

[0005] Preferably, in step (1), the material of the semi-split equalizing plate is fiberglass reinforced plastic.

[0006] Preferably, in step (1), the structure of the wedge equalizing plate forming mold is a male mold; the mold surface is machined and manufactured based on the outer shape surface of the wedge part.

[0007] Preferably, the top sharp-corner area of the wedge equalizing plate forming mold is increased by 3 mm based on the outer shape surface of the wedge part.

[0008] Preferably, in step (1), forming the semi-split equalizing plate includes the following steps: 1) Lay 5 to 6 layers of glass fiber prepreg on the wedge-shaped equalizing plate forming mold, lay the prepreg to the end surface of the mold to form a flange, and add reinforcement layers on both sides of the top sharp corner. The reinforcement layers are laid evenly and transitionally to form an equalizing plate preform; 2) The pressure balancing plate preform is placed in an autoclave for curing and molding. After the pressure balancing plate is demoulded, it is divided along the central axis of the top sharp corner, and the other areas are integral structures to form a semi-split pressure balancing plate.

[0009] Preferably, in step 1), the width of the reinforcement layer does not exceed 20 mm.

[0010] Preferably, in step (2), forming the part preform comprises the following steps: laying carbon fiber prepreg on the wedge forming mold according to design requirements, filling the carbon fiber prepreg tow in the sharp corner area of ​​the final layer surface, and then wrapping it with prepreg strips to form the part preform.

[0011] Preferably, the prepreg strip has a width of 10 mm.

[0012] Compared with the prior art, the present invention has the following advantages: reduced manufacturing cost, shortened manufacturing cycle, improved production efficiency, and guaranteed the accuracy of the wedge angle shape. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 2 is a schematic diagram of the structure of a wedge part in an embodiment of the present invention; Figure 2 Schematic diagram of the structure of the wedge-type pressure plate forming die in an embodiment of the present invention; Figure 3 Schematic diagram of the wedge shape inspection mold structure in an embodiment of the present invention; Figure 4 It is a schematic diagram of the assembly structure of the parts preform and the semi-split glass fiber reinforced plastic pressure balancing plate in an embodiment of the present invention; Figure 5 Schematic diagram of the wedge shape inspection mold in use according to an embodiment of the present invention; Figure 4 Among them, 1. wedge forming mold; 2. part preform; 3. semi-split glass fiber reinforced plastic equalizing plate; 4. reinforcement layer. DETAILED DESCRIPTION

[0014] The following is combined with Figures 1-5 The present invention is further described in detail: A composite material wedge forming method comprises the following steps: (1) Customized wedge pressure plate forming mold, such as Figure 2 As shown, the mold structure is a male mold, and the mold surface is a wedge part (such as Figure 1 The outer surface is manufactured based on the reference, and the sharp corner area at the top of the mold is raised by about 3mm on the basis of the outer surface of the wedge part; (2)Customize a wedge-shaped profile inspection mold, as Figure 3 shown. The inspection mold is a two-piece split female mold, and its surface is machined based on the outer profile of the wedge-shaped part; (3)Lay 5 to 6 layers of glass fiber prepreg on the wedge-shaped equalizing plate forming mold. The prepreg needs to be laid to the end face of the mold to form a flange, and a reinforcing layer 4 with a width not exceeding 20 mm is additionally pasted on both sides of the top corner. The layup of the reinforcing layer is evenly transitioned to form a preform of the equalizing plate; (4)Place the preform of the equalizing plate in an autoclave for curing and forming. After the equalizing plate is removed from the mold, it is split along the central axis of its top corner, and the other areas are integral structures to form a semi-split fiberglass equalizing plate 3; (5)As Figure 4 shown, lay carbon fiber prepreg on the wedge-shaped forming mold 1 according to the design requirements, fill the surface corner area of the last layup with carbon fiber prepreg tows, and then wrap it with a prepreg strip with a width of about 10 mm to form a part preform 2. Then, place the semi-split fiberglass equalizing plate 3 on the surface of the part preform, and ensure that the height of the corner filling with tows of the part preform 2 is flush with the top of the corner of the semi-split fiberglass equalizing plate 3; (6)Place the assembly of the part preform 2 and the semi-split fiberglass equalizing plate 3 in an autoclave for curing and forming; (7)As Figure 3 , 5 shown, use the wedge-shaped profile inspection mold to process and trim the corner allowance of the wedge, and then use a simple profile inspection template to check and review the processed wedge-shaped corner profile.

[0015] The above embodiments are only the preferred embodiments of the present invention and do not constitute a limitation to the present invention. Any extension, deformation, equivalent replacement, etc. made by those of ordinary skill in the art without departing from the principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A composite material wedge forming method, characterized in that: The following steps are involved: (1) Using a wedge-shaped equalizing plate forming mold to make a semi-split equalizing plate; (2) laying carbon fiber prepreg on the wedge forming mold to form a part preform, and assembling and packaging the semi-split pressure plate and the part preform; (3) Transferring the assembly of the semi-split pressure equalizing plate and the preformed parts to an autoclave for curing and molding; (4) Use the appearance inspection mold and appearance inspection template to process and trim the appearance of the parts after curing.

2. The composite material wedge forming method according to claim 1, characterized in that: In step (1), the material of the semi-split pressure equalizing plate is glass fiber reinforced plastic.

3. The composite material wedge forming method according to claim 1, characterized in that: In step (1), the structure of the mold for forming the wedge equalizing plate is a male mold; and the mold surface is manufactured based on the outer surface of the wedge part.

4. The composite material wedge forming method according to claim 3, characterized in that: The top corner area of ​​the wedge equalizing plate forming mold is raised by 3mm based on the outer surface of the wedge part.

5. The composite material wedge forming method according to claim 1, characterized in that: In step (1), forming a semi-split pressure equalizing plate includes the following steps: 1) Lay 5 to 6 layers of glass fiber prepreg on the wedge-shaped equalizing plate forming mold, lay the prepreg to the end surface of the mold to form a flange, and add reinforcement layers on both sides of the top sharp corner. The reinforcement layers are laid evenly and transitionally to form an equalizing plate preform; 2) The preform of the pressure balancing plate is placed in an autoclave for curing and molding. After the pressure balancing plate is demoulded, it is divided along the central axis of the top sharp corner. The other areas are integral structures to form a semi-split pressure balancing plate.

6. The composite material wedge forming method according to claim 5, characterized in that: In step 1), the width of the reinforcement layer shall not exceed 20 mm.

7. The composite material wedge forming method according to claim 1, characterized in that: In step (2), forming a part preform includes the following steps: laying carbon fiber prepreg on the wedge forming mold according to the design requirements, filling the carbon fiber prepreg tow in the sharp corner area of ​​the final layer surface, and then wrapping it with prepreg strips to form a part preform.

8. The composite material wedge forming method according to claim 7, characterized in that: The width of the prepreg strip is 10 mm.

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