CN116409014A - Preparation method of bell-shaped flexible aramid paper honeycomb - Google Patents

Abstract

The invention relates to the technical field of composite materials, in particular to a method for preparing a bell-shaped flexible aramid paper honeycomb. The aramid paper is introduced between the forming roller and the transfer roller, and the aramid paper is placed between the teeth of the forming roller and the transfer roller. Under the action of the bite force of the roller teeth, the curved surface shape is formed; the aramid paper moves along the circumferential direction of the transfer roller under the action of traction, and passes through the tangent position between the glue roller and the transfer roller. The core strip glue is transferred to the surface of the aramid paper; the aramid paper is dislocated and stacked to form a laminated board, and then the laminated board is heated and pressed on a hot press by precise pressure tooling to cure the core strip glue; Honeycomb preparation was carried out on the laminated board to obtain a bell-shaped flexible aramid paper honeycomb. The bell-shaped flexible aramid paper honeycomb core material can avoid problems such as cell deformation, cell extrusion, and node cracking due to stress concentration in the honeycomb core material. It can be extended to other fields such as rail transit and aerospace, and used for curved surface composite interlayers Preparation of structures.

Description

A kind of preparation method of bell-shaped flexible aramid paper honeycomb

technical field

The invention relates to the technical field of composite materials, in particular to a method for preparing a bell-shaped flexible aramid paper honeycomb.

Background technique

Aramid paper honeycomb is a kind of high strength, excellent environmental resistance, and as the core material of sandwich structure, it is widely used in the field of aviation, spaceflight and rail transportation. In particular, regular hexagonal aramid paper honeycombs are the most widely used, but because the cemented sides and free sides of regular hexagonal cells are straight lines and have high rigidity, they can only be applied to flat plates and wavy shapes with small curvature.

The bell-shaped flexible aramid paper honeycomb core material is completely different from the traditional regular hexagon. Because the free edge of the bell-shaped honeycomb cell is corrugated, the cell wall can follow the curvature change of the complex surface, so the cell will not have any damage. Destruction can meet the forming requirements of large curvature. The production of conventional regular hexagonal honeycomb is first to glue the aramid paper, press it, stretch it, dip it, cure it, and cut it into pieces. Bell-shaped flexible aramid paper honeycombs are difficult to manufacture using conventional regular hexagonal honeycombs. The core material has defects such as honeycomb cell deformation and node cracking during the application of large-curvature surface structures.

Contents of the invention

(1) Technical problems to be solved

The embodiment of the present invention provides a method for preparing a bell-shaped flexible aramid paper honeycomb, which solves the technical problem that it is difficult to manufacture a bell-shaped flexible aramid paper honeycomb using a conventional regular hexagonal honeycomb.

(2) Technical solution

Embodiments of the present invention propose a method for preparing a bell-shaped flexible aramid paper honeycomb, comprising steps:

S1, the aramid paper is introduced between the forming roller and the transfer roller, and the aramid paper forms a curved surface under the action of the bite force of the teeth of the forming roller and the teeth of the transfer roller;

S2, the aramid paper moves along the circumferential direction of the transfer roller under the action of traction, and passes through the tangent position between the glue roller and the transfer roller, and transfers the core glue on the glue roller to the aramid under the action of pressure paper surface;

S3, the aramid paper is dislocated and laminated to form a laminated board, and then the laminated board is heated and pressed on a hot press by precise pressure tooling to cure the core strip glue;

S4, honeycomb preparation is performed on the laminated board to obtain a bell-shaped flexible aramid paper honeycomb.

Further, the pitch between two adjacent core strips of the glue roller in the circumferential direction is multiple times the pitch between two adjacent tooth crests of the aramid paper.

Further, the pitch between two adjacent core strips of the glue roller in the circumferential direction is twice the pitch between two adjacent tooth peaks of the aramid paper.

Further, in S1, the thermoforming roller has a heating function, and the heating temperature range is 150°C to 200°C.

Further, the transfer roller in S1 absorbs the aramid paper by vacuum, and when the aramid paper is pulled along the circumference of the transfer roller, the transfer roller will absorb the aramid paper on the surface without falling off.

Further, in the gluing process in S2, the transfer roller applies pressure to the gluing roller, and the pressure ranges from 0.1 MPa to 0.7 MPa.

Further, in S3, the precision press tooling is wave-shaped, and the size is consistent with the teeth of the forming roller.

Further, the honeycomb preparation in S4 includes stretching, shaping, dipping, curing and slice-cutting process operations.

(3) Beneficial effect

In summary, the present invention carries out high-temperature curved surface forming on the aramid paper through the mutual cooperation of the forming roller and the transfer roller, and then the formed aramid paper is glued at intervals through the transfer roller and the glue roller, and the core strip glue is regularly transferred to the aramid paper. The position of the aramid paper is designated to avoid glue on the crest of each group of aramid paper, which will affect the stretching and forming. Precise glue application greatly improves the production efficiency and the uniformity of the cell size of the product. The bell-shaped flexible aramid paper honeycomb core material prepared at the same time can avoid the problems of cell deformation, cell extrusion and node cracking due to stress concentration in the honeycomb core material, and can be extended to other fields such as rail transportation and aerospace for use in Fabrication of curved composite sandwich structures.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the accompanying drawings required in the embodiments of the present invention. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For Those of ordinary skill in the art can also obtain other drawings based on these drawings without making creative efforts.

Fig. 1 is the overall structure schematic diagram of a bell-shaped flexible aramid paper honeycomb core material forming glue coating mechanism used in the preparation method of a bell-shaped flexible aramid paper honeycomb of the present invention.

FIG. 2 is a partially enlarged schematic diagram of FIG. 1 .

Fig. 3 is a schematic diagram of a formed bell-shaped flexible aramid paper honeycomb core material.

In the figure: 1. Forming roller; 2. Transfer roller; 3. Coating roller; 4. Aramid paper; 5. First roller teeth; 6. Second roller teeth; 7. Glue storage unit; 8. Core glue .

Detailed ways

Embodiments of the present invention will be further described in detail below in conjunction with the accompanying drawings and examples. The detailed description and accompanying drawings of the following embodiments are used to illustrate the principles of the present invention, but cannot be used to limit the scope of the present invention, that is, the present invention is not limited to the described embodiments, without departing from the spirit of the present invention Any modification, substitution and improvement of parts, components and connection methods are covered under.

It should be noted that, in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and embodiments.

Please refer to Fig. 1-Fig. 3, a bell-shaped flexible aramid paper honeycomb core material molding and gluing mechanism used in the preparation method of a bell-shaped flexible aramid paper honeycomb of the present invention, including: from top to bottom The forming roller 1, the transfer roller 2 and the gluing roller 3 are provided, and the rotating shafts of the forming roller 1 and the transfer roller 2 are meshed with each other through gears to realize synchronous rotation, and the transfer roller 2 and the gluing roller The rotating shafts of the rollers 3 are meshed with each other through gears to realize synchronous rotation. The forming roller 1 is provided with the first roller teeth 5 for forming the aramid paper 4, and the transfer roller 2 corresponds to the first roller teeth 5 The second roller tooth 6 matched with it is provided, and the aramid paper 4 is passed between the forming roller 1 and the transfer roller 2, and the forming roller 1 and the transfer roller 2 are rotated synchronously through gear transmission, and the The first roller teeth 5 and the second roller teeth 6 cooperate with each other to perform high-temperature curved surface forming on the passing aramid paper 4 .

A glue storage unit 7 is arranged on the glue application roller 3 , and the pitch N between the glue storage units 7 in the circumferential direction is twice the pitch M of the first roller teeth 5 or the second roller teeth 6 . The formed aramid paper 4 passes through the transfer roller 2 and the glue roller 3 in reverse, because the pitch N between the glue storage unit 7 in the circumferential direction is the pitch M of the first roller teeth 5 or the second roller teeth 6 Twice as much as that of the aramid paper 4, so that the gap coating of the aramid paper 4 is realized, and the core strip glue 8 is regularly transferred to the designated position of the aramid paper 4, so as to avoid the glue on the crest of each group of aramid paper 4, which will affect the stretching Forming and precise glue application greatly improve the production efficiency and the uniformity of the cell size of the product.

Embodiments of the present invention propose a method for preparing a bell-shaped flexible aramid paper honeycomb, comprising steps:

S1, the aramid paper 4 is introduced between the forming roller 1 and the transfer roller 2, and the aramid paper 4 forms a curved surface shape under the action of the teeth of the forming roller 1 and the transfer roller 2 under the bite force;

S2, the aramid paper 4 moves along the circumferential direction of the transfer roller 2 under the action of traction, passes through the position where the glue roller 3 is tangent to the transfer roller 2, and glues the core strip on the glue roller 3 under the action of pressure. 8 transferred to the surface of aramid paper 4;

S3, dislocation-stacking the aramid paper 4 to form a laminated board, and then heating and pressing the laminated board on a hot press through precise pressure tooling, so that the core strip glue 8 is cured;

S4, honeycomb preparation is performed on the laminated board to obtain a bell-shaped flexible aramid paper honeycomb.

In some embodiments, the pitch N between two adjacent core strips 8 of the gumming roller 3 in the circumferential direction is a multiple of the tooth pitch M between two adjacent tooth crests of the aramid paper 4 . Further, the pitch N between two adjacent core strip glues 8 of the gluing roller 3 in the circumferential direction is twice the pitch M between two adjacent tooth peaks of the aramid paper 4, realizing the The paper 4 is glued at intervals, and the core strip glue 8 is regularly transferred to the designated position of the aramid paper 4, so as to avoid the wave crest of each group of aramid paper 4 from having glue, which will affect the stretching and forming, and the glue is applied accurately, which greatly improves the production Efficiency, improve the uniformity of product cell size.

In some embodiments, in S1, the thermoforming roll 1 has a heating function, and the heating temperature ranges from 150°C to 200°C.

In some embodiments, the transfer roller 2 in S1 absorbs the aramid paper 4 by vacuum, and when the aramid paper 4 moves along the circumference of the transfer roller 2, the transfer roller 2 absorbs the aramid paper 4 on the surface without falling off .

In some embodiments, during the gluing process in S2, the transfer roller 2 applies pressure to the gluing roller 3, and the pressure ranges from 0.1 MPa to 0.7 MPa.

In some embodiments, the precise pressing tool in S3 is wave-shaped, and its size is consistent with the teeth of the forming roller 1 .

In some embodiments, the honeycomb preparation in S4 includes stretching, shaping, dipping, curing and slicing process operations.

Example:

Step 1: roll forming, heat the forming roll 1 to 195°C±5°C, pass the aramid paper 4 under a certain tension through the forming roll 1 and the transfer roll 2 in sequence, and the aramid paper 4 is formed on the forming roll 1 and the transfer roll 2 The surface shape is formed under the action of the bite force between the two.

Step 2: Applying glue, under the action of traction, the curved aramid paper 4 moves forward along the circumferential direction of the transfer roller 2, passes through the tangent position between the glue roller 3 and the transfer roller 2, and under the action of pressure will The core glue 8 on the glue roller 3 is transferred to the surface of the aramid paper 4 . During the gluing process, the transfer roller 2 needs to apply pressure to the gluing roller 3, and the preferred pressure range is 0.1MPa-0.7MPa.

Step 3: Lamination and pressing. According to the traditional honeycomb lamination method, dislocation lamination is carried out to form a laminated board, and then the laminated board is heated and pressed on a hot press using precise pressure tooling to cure the core strip glue. The precision press tooling is wave-shaped, and the size of the wave is consistent with that of the first tooth of the forming roller.

Step 4: According to the traditional honeycomb preparation method, the laminated board is stretched, shaped, dipped and cured, and the bell-shaped flexible aramid paper honeycomb is prepared.

It should be clear that each embodiment in this specification is described in a progressive manner, and the same or similar parts of each embodiment can be referred to each other, and each embodiment focuses on the differences from other embodiments. place. The present invention is not limited to the specific steps and structures described above and shown in the drawings. Also, for the sake of brevity, detailed descriptions of known methods and techniques are omitted here.

The above descriptions are only examples of the present application, and are not intended to limit the present application. Various modifications and changes may be made to this application by those skilled in the art without departing from the scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the scope of the claims of the present application.

Claims (8)

1. The preparation method of the bell-shaped flexible aramid paper honeycomb is characterized by comprising the following steps of:

s1, introducing aramid paper between a forming roller and a transfer roller, wherein the aramid paper forms a curved surface shape under the action of the biting force of the roller teeth of the forming roller and the roller teeth of the transfer roller;

s2, the aramid paper moves along the circumferential direction of the transfer roller under the action of traction force, and the core strip glue on the glue spreading roller is transferred to the surface of the aramid paper under the action of pressure through the tangential position of the glue spreading roller and the transfer roller;

s3, carrying out dislocation lamination on the aramid paper to form a laminated plate, and then heating and pressurizing the laminated plate on a hot press through an accurate pressurizing tool to solidify the core strip glue;

s4, carrying out honeycomb preparation on the laminated plate to obtain the bell-shaped flexible aramid paper honeycomb.

2. The method for producing a bell-shaped flexible aramid paper honeycomb according to claim 1, wherein the pitch between two adjacent core stripes of the glue spreader in the circumferential direction is multiple times the pitch between two adjacent teeth peaks of the aramid paper.

3. The method for producing a bell-shaped flexible aramid paper honeycomb according to claim 2, wherein the pitch between two adjacent core stripes of the glue applicator in the circumferential direction is twice the pitch between two adjacent teeth peaks of the aramid paper.

4. The method for preparing bell-shaped flexible aramid paper honeycomb according to claim 1, wherein the thermoforming roller has a heating function in the step S1, and the heating temperature is 150-200 ℃.

5. The method for producing a bell-shaped flexible aramid paper honeycomb according to claim 1, wherein the transfer roller in S1 adsorbs the aramid paper by vacuum, and the transfer roller adsorbs the aramid paper to the surface without falling off when the aramid paper moves along the circumferential traction of the transfer roller.

6. The method for producing a bell-shaped flexible aramid paper honeycomb according to claim 1, wherein in the step S2 of the glue application, the transfer roller applies a pressure to the glue application roller in a pressure range of 0.1MPa to 0.7MPa.

7. The method for manufacturing a bell-shaped flexible aramid paper honeycomb according to claim 1, wherein the precise pressurizing tool in S3 is wave-shaped, and the size of the precise pressurizing tool is consistent with the size of the teeth of the forming roller.

8. The method for preparing bell-shaped flexible aramid paper honeycomb according to claim 1, wherein the honeycomb preparation in S4 comprises stretching, shaping, dipping, curing and slicing process operations.

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