A mold and forming method of interlayer reinforced composite material energy-absorbing circular tube

Abstract

The present invention proposes a mold for an interlayer reinforced composite material energy-absorbing circular tube and a molding method thereof, and belongs to the technical field of composite material processing. The problem of low interlayer bearing capacity of composite material circular tubes is solved. It includes a grid skeleton and a petal unit. The grid skeleton is divided into a plurality of module units by a horizontal and vertical cross beam structure. The module unit is concave, and the petal unit is convex, which can be embedded in each module unit of the mold skeleton. The mold of the present invention is a skeleton structure + petal unit combination mode, and is simple to disassemble and assemble. The present invention is easy to operate when completing interlayer continuous fiber reinforcement. After interlayer reinforcement, the energy absorption performance and bearing capacity of the composite material circular tube are greatly improved.

Description

Technical Field

[0001] The invention belongs to the technical field of composite material processing, and in particular relates to a mold for an interlayer reinforced composite material energy-absorbing circular tube and a molding method thereof. Background Art

[0002] Currently, most commonly used energy-absorbing devices use metal structures. With the demand for lightweight structural design, traditional metal steel and aluminum alloy energy-absorbing structures can no longer meet the demand for anti-collision energy absorption. Fiber composite materials are increasingly used in rail transportation, aerospace and other fields due to their high specific strength, specific stiffness and other mechanical properties, as well as their designability and lightweight characteristics.

[0003] Compared with traditional metal materials, composite materials can improve the specific energy absorption of the structure while also reducing weight. The specific rigidity and strength of fiber composite materials in the fiber direction are better than those of metal materials, but the interlaminar performance of composite materials is much lower than that of metal materials. When the energy absorption device is subjected to external impact, the interlaminar stress of the composite structure exceeds the allowable value of the material during the load-bearing process, resulting in delamination, which reduces the energy absorption efficiency. Summary of the invention

[0004] In view of this, the present invention aims to provide a mold and a molding method for an interlayer reinforced composite material energy-absorbing circular tube, so as to solve the problem of low interlayer bearing capacity of the composite material circular tube.

[0005] To achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a mold for an interlayer reinforced composite energy-absorbing circular tube, comprising a grid skeleton and a petal unit, wherein the grid skeleton is divided into a plurality of module units by a horizontal and vertical cross beam structure, the module units are concave, and the petal units are convex, which can be embedded in each module unit of the mold skeleton.

[0006] A method for preparing an interlayer reinforced composite material energy absorbing circular tube using the mold of the interlayer reinforced composite material energy absorbing circular tube specifically comprises the following steps:

[0007] (1) Mold installation: install the petal units on the corresponding module units of the grid skeleton;

[0008] (2) Processing the assembled mold;

[0009] (3) After the product is formed, the petal units are removed from the grid skeleton one by one from the inner side of the round tube;

[0010] (4) After disassembling some of the petal units, the reinforcing fibers are inserted through the thickness direction of the product according to the designed position to strengthen the product layers;

[0011] (5) After the petal unit has been disassembled and the reinforcing fibers have penetrated the product, the petal unit is installed back to its original position, the petal unit below is disassembled, and the remaining part of the product is reinforced, thus ensuring the continuity of the reinforcing fibers between the layers of the overall product;

[0012] (6) After the product is reinforced between layers, it is cured.

[0013] Furthermore, the process molding method adopts winding molding, lay-up molding, hand lay-up molding or RTM molding.

[0014] Furthermore, in step (3), the petal unit is disassembled by first removing the positioning pin hole, then removing the bolt fastener, and finally lifting the petal unit out through the top screw hole.

[0015] Furthermore, in step (3), when disassembling the petal unit, it is disassembled according to the continuous direction of the interlayer reinforcing fibers.

[0016] Furthermore, in step (3), the petal units corresponding to the hole positions with the fiber continuity direction in front are first disassembled.

[0017] Furthermore, in step (4), interlayer Z-direction continuous fiber reinforcement is performed between the layers of the tube body, which increases the interlayer bearing capacity of the tube body and improves the energy absorption efficiency.

[0018] Furthermore, the reinforcing fiber is selected from carbon fiber, glass fiber, aramid fiber or basalt fiber.

[0019] Furthermore, the matrix material is selected from epoxy resin, polyurethane resin or polyester resin.

[0020] Compared with the prior art, the mold and forming method of the interlayer reinforced composite material energy-absorbing circular tube of the present invention have the following beneficial effects:

[0021] (1) The mold of the interlayer reinforced composite material energy-absorbing circular tube described in the present invention is a skeleton structure + petal unit combination mode, which is easy to disassemble and assemble.

[0022] (2) The present invention is easy to operate when completing interlayer continuous fiber reinforcement, and the energy absorption performance and bearing capacity of the composite material circular tube after interlayer reinforcement are greatly improved.

[0023] (3) The product prepared by the present invention has a lower cost than the three-dimensional woven product, and the method is suitable for engineering application and mass production of products. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0025] Figure 1 It is a schematic structural diagram of an interlayer reinforced composite material energy-absorbing circular tube according to the present invention;

[0026] Figure 2 It is a side view of an interlayer reinforced composite material energy-absorbing circular tube according to the present invention;

[0027] Figure 3 It is a structural schematic diagram of the mold skeleton of the present invention;

[0028] Figure 4 A side view of the mold skeleton of the present invention;

[0029] Figure 5 It is a structural schematic diagram of half side of the module unit of the mold skeleton of the present invention;

[0030] Figure 6 It is a schematic diagram of the overall structure of the mold skeleton and the petal unit of the present invention;

[0031] Figure 7 for Figure 6 Side view of

[0032] Figure 8 It is a structural schematic diagram of the petal unit of the present invention;

[0033] Fig. 9 Schematic diagram of mold assembly;

[0034] Fig.10 This is a schematic diagram of the completed mold assembly;

[0035] Fig.11 The schematic diagram of product molding completion;

[0036] Fig.12 This is a schematic diagram for disassembling the petal unit;

[0037] Fig.13 A schematic diagram of the sequence of disassembling the petal unit on the product;

[0038] Fig.14 A schematic diagram of the sequence of disassembling the mold of the petal unit;

[0039] Fig.15 This is a schematic diagram of the continuous direction of the reinforcing fibers between product layers;

[0040] Fig.16 It is a schematic diagram of product inter-layer enhancement;

[0041] in Figure 13-Figure 15 The "-1", "-2", "-3", "-4", "-5" and "-6" marked on the top indicate the marking of the petal units. Fig.15The lines represent continuous fiber orientations of 1-2-3-4-5-6.

[0042] In the figure: 1-composite material energy absorbing tube, 2-grid frame, 3-module unit, 4-petal unit, 5-threaded fastening through hole, 6-bolt hole, 7-locating pin hole, 8-No. 2 locating pin hole, 9-top screw hole. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely explain the technical solutions in the embodiments of the present invention. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict, and the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0044] 1. Specific implementation method 1, see Figure 1-8 To illustrate the present embodiment, a mold for an interlayer reinforced composite energy-absorbing circular tube comprises a grid skeleton 2 and petal units 4. The grid skeleton 2 is divided into a plurality of module units 3 by horizontal and vertical cross beam structures. The module units 3 are concave and the petal units 4 are convex and can be embedded in each module unit 3 of the mold skeleton 2.

[0045] The mold of the interlayer reinforced composite material energy-absorbing circular tube includes a grid skeleton 2 and a petal unit 4.

[0046] The grid framework 2 is composed of horizontal and vertical cross beam structures (such as Figure 3-4 The skeleton structure serves as a supporting structure for the round tube mold, and each petal unit 4 is installed and connected in the skeleton structure.

[0047] Each module unit 3 of the grid skeleton 2 is concave, and is provided with threaded holes 6 and No. 1 positioning pin holes 7 on the periphery. After the pin holes are positioned with the petal unit 4, the bolts are fastened to connect (such as Figure 5 shown).

[0048] The petal units 4 are convex and distributed in each module unit 3 of the grid skeleton 2 (such as Figure 6-7 shown).

[0049] At the edge of the petal unit 4, through holes are evenly arranged, corresponding to the hole positions of the module unit 3 of the grid skeleton 2, and the through holes are divided into threaded fastening through holes 5, second positioning pin holes 8 and top screw holes 9 for disassembling the mold (such as Figure 8 shown).

[0050] The method for forming the interlayer reinforced composite material energy-absorbing circular tube specifically comprises the following steps:

[0051] (1) Mold installation: install the petal unit 4 on the module unit 3 of the corresponding grid skeleton 2, such as Fig. 9As shown. The mold assembly is completed as shown. Fig.10 shown.

[0052] (2) The assembled mold is processed and formed. Composite energy absorbing tube (such as Figure 1-2 As shown in the figure, it is a circular tubular structure, and the molding process can be winding molding, lay-up molding, hand lay-up molding, RTM (resin transfer molding process) and other molding methods. Fig.11 shown.

[0053] (3) At this time, the product has not yet been reinforced with continuous fibers between layers, which is the key to mold design and process design. Since the mold design is a detachable combination of the grid frame 2 + the petal unit 4, after the product is formed, the petal units 4 are removed one by one from the grid frame 2 from the inside of the round tube, such as Fig.12 shown.

[0054] To disassemble the petal unit 4, first remove the second positioning pin hole 8, then remove the bolt fastener, and finally remove the petal unit 4 through the top screw hole 9. When disassembling the petal unit 4, it is necessary to disassemble it according to the continuous direction of the interlayer reinforcement fibers. For example, if the continuous fibers go in the direction of 1-2-3-4-5-6, first disassemble the petal unit 4 corresponding to the hole position. Figure 13-14 shown.

[0055] (4) After disassembling part of the petal unit 4, the reinforcing fibers are inserted through the thickness direction of the product according to the designed position to perform interlayer reinforcement of the product.

[0056] After the tube body is preformed, interlayer Z-direction continuous fiber reinforcement is performed between the tube layers through a detachable mold, which increases the interlayer bearing capacity of the tube body and improves the energy absorption efficiency.

[0057] After the petal unit 4 has been disassembled and the reinforcing fibers have penetrated the product, the petal unit 4 is installed back to its original position, and the petal unit 4 below is disassembled, and the remaining part of the product is reinforced. This ensures the continuity of the reinforcing fibers between the layers of the entire product. Fig.16 shown.

[0058] (5) After the petal unit 4 has been disassembled and the reinforcing fibers have penetrated the product, the petal unit 4 is installed back to its original position, the petal unit 4 below is disassembled, and the remaining part of the product is reinforced, thus ensuring the continuity of the reinforcing fibers between the layers of the entire product;

[0059] (6) After the product is reinforced between layers, it is cured. When the product is demoulded after curing, the skeleton mold and the petal unit are demoulded as a whole to ensure the rigidity during demoulding.

[0060] The reinforcing fibers can be carbon fiber, glass fiber, aramid fiber or basalt fiber.

[0061] The matrix material is selected from epoxy resin, polyurethane resin or polyester resin.

[0062] This mold design method and interlayer reinforcement method are suitable for the design and forming of polygonal structures such as circles, quadrilaterals, and hexagons.

[0063] The embodiments of the present invention disclosed above are only used to help illustrate the present invention. The embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. According to the content of this specification, many modifications and changes can be made. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well.

Claims

1. A method for preparing an interlayer reinforced composite material energy absorbing round tube using a mold for an interlayer reinforced composite material energy absorbing round tube, characterized in that: The specific steps include: (1) Mold installation, installing the petal units (4) correspondingly on the module units (3) of the corresponding grid skeleton (2); (2) Processing the assembled mold; (3) After the product is formed by the process, the petal units (4) are taken out from the grid frame (2) one by one from the inner side of the round tube; (4) After disassembling part of the petal unit (4), the reinforcing fibers are inserted through the thickness direction of the product according to the designed position to perform interlayer reinforcement of the product; The interlayer Z-direction continuous fiber reinforcement is carried out between the layers of the tube body to increase the interlayer bearing capacity of the tube body and improve the energy absorption efficiency; (5) After the petal unit (4) has been disassembled and the reinforcing fibers have penetrated the product, the petal unit (4) is installed back to its original position, the petal unit (4) below is disassembled, and the remaining part of the product is reinforced, thereby ensuring the continuity of the reinforcing fibers between the layers of the entire product; (6) After the product is reinforced between layers, it is cured; A mould for an interlayer reinforced composite material energy-absorbing circular tube comprises a grid frame (2) and a petal unit (4), wherein the grid frame (2) is divided into a plurality of module units (3) by a transverse and longitudinal cross beam structure, wherein the module units (3) are concave and the petal units (4) are convex and can be embedded in each module unit (3) of the grid frame (2).

2. The preparation method according to claim 1, characterized in that: The molding process adopts winding molding, lay-up molding, hand lay-up molding or resin transfer molding process.

3. The preparation method according to claim 1, characterized in that: In step (3), the petal unit (4) is disassembled by first removing the No. 2 positioning pin hole (8), then removing the bolt fasteners, and finally lifting the petal unit (4) through the top screw hole (9).

4. The preparation method according to claim 3, characterized in that: In step (3), when disassembling the petal unit (4), it is disassembled according to the continuous direction of the interlayer reinforcing fibers.

5. The preparation method according to claim 4, characterized in that: In step (3), the petal unit (4) corresponding to the hole position with the fiber continuity direction in front is first disassembled.

6. The preparation method according to claim 1, characterized in that: In step (6), when the product is demoulded after solidification, the grid skeleton (2) and the petal units (4) are demoulded as a whole to ensure the rigidity during demoulding.

7. The preparation method according to claim 1, characterized in that: The reinforcing fibers can be carbon fiber, glass fiber, aramid fiber or basalt fiber.

8. The preparation method according to claim 1 or 7, characterized in that: The matrix material is selected from epoxy resin, polyurethane resin or polyester resin.

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