A bifurcated orthogonal three-dimensional woven preform and its weaving method

Abstract

The present invention provides an orthogonal three-dimensional woven preform containing bifurcations and a weaving method thereof, relating to the technical field of textile composite materials. The present invention designs and weaves an orthogonal three-dimensional woven preform containing bifurcations to achieve near-net-shape manufacturing of bifurcated structural parts; by designing the weft yarn path, the out-of-plane strength (in the direction in which each branch extends) and lateral strength of the orthogonal three-dimensional woven composite material containing bifurcations can be improved, and the total weight can be reduced. The weaving method of the present invention is simple to operate, and the obtained orthogonal three-dimensional woven preform containing bifurcations has stable quality.

Description

Technical Field

[0001] The invention relates to the technical field of textile composite materials, and in particular to an orthogonal three-dimensional woven preform containing bifurcations and a weaving method thereof. Background Art

[0002] In recent years, composite structural components have been widely used due to their technical advantages such as high specific strength, high specific stiffness, strong designability, and corrosion resistance. With the improvement of design and manufacturing capabilities, the forms, application environments, and loads of composite structural components have become increasingly complex. Composite materials containing bifurcations, especially those with special cross-sectional shapes such as "T", "H", "I", "π", and "F", are widely used in connection structures and reinforcement structures.

[0003] Traditional bifurcated composite structures are often manufactured using a layer-by-layer stacking method. Bifurcated structures suffer from low structural strength under out-of-plane loads, and local reinforcement between layers is often achieved through methods such as needling and stitching. However, these methods compromise fiber integrity and have limited applicability. Furthermore, due to process limitations, this method requires extensive post-processing and exhibits relatively inconsistent quality. Summary of the Invention

[0004] The object of the present invention is to provide an orthogonal three-dimensional woven preform containing bifurcations and a weaving method thereof. The weaving method of the present invention is simple to operate, and the obtained orthogonal three-dimensional woven preform containing bifurcations has stable quality.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a weaving method for an orthogonal three-dimensional woven preform containing bifurcations, comprising the following steps:

[0007] (1) setting weaving parameters according to the geometric dimensions of the orthogonal three-dimensional woven preform; the weaving parameters include the number of warp yarn layers, the warp yarn density, the number of weft yarn layers, and the weft yarn density;

[0008] (2) setting a bifurcation mode and a bifurcation position according to the geometric dimensions of the orthogonal three-dimensional woven preform in step (1) and the mechanical performance requirements of the composite material structural component, and determining a bifurcation pattern of the orthogonal three-dimensional woven preform;

[0009] (3) designing a weft yarn path according to the conditions set in steps (1) and (2) to obtain a design scheme for an orthogonal three-dimensional woven preform bifurcated structure;

[0010] (4) According to the design scheme described in step (3), three-dimensional weaving technology is used for weaving to obtain an orthogonal three-dimensional woven preform containing bifurcations.

[0011] Preferably, the step (1) comprises:

[0012] The number of warp yarn layers is The orthogonal three-dimensional woven preform is divided into m warp yarn layers The branches of m-branch preform are obtained;

[0013] For the bifurcation-free region, the number of warp yarn layers of the orthogonal 3D woven preform and number of weft yarn layers The relationship is

[0014] For the m-bifurcation region, the sum of the weft yarn layers of the orthogonal three-dimensional woven preform is The number of weft yarns in each branch is

[0015] Preferably, the step (2) includes: controlling the number of warp yarn layers in each branch according to the designed thickness of each branch after the m bifurcation The thickness of the branch is controlled; and the starting number of layers is determined according to the position corresponding to the required number of layers so as to increase the weft yarn two-ply at the starting number of layers.

[0016] Preferably, the bifurcated structure includes a 1-m bifurcated structure, an mm bifurcated structure, an m-1-m bifurcated structure, a k-bifurcated-m bifurcated structure or a local bifurcated structure.

[0017] Preferably, the 1-m bifurcation structure includes a 1-2 bifurcation structure or a 1-3 bifurcation structure.

[0018] Preferably, the mm bifurcation structure comprises a 2-2 bifurcation structure.

[0019] Preferably, the m-1-m bifurcated structure includes a 2-1-2 bifurcated structure.

[0020] Preferably, the k-forked-m-forked structure comprises a 3-2-forked structure.

[0021] Preferably, the weaving comprises: sequentially lifting the warp yarns above the position of the target weft yarn in order from bottom to top, and sequentially inserting the weft yarns.

[0022] The present invention provides an orthogonal three-dimensional woven preform containing bifurcations obtained by the weaving method described in the above technical solution.

[0023] The present invention provides a method for weaving an orthogonal three-dimensional woven preform containing bifurcations. The method designs and weaves the bifurcated orthogonal three-dimensional woven preform to achieve near-net-shape manufacturing of bifurcated structural components. The weft yarn path is designed to improve the out-of-plane strength (in the direction in which each branch extends) and lateral strength of the bifurcated orthogonal three-dimensional woven composite material, while reducing the overall weight. The weaving method is simple to operate, and the resulting bifurcated orthogonal three-dimensional woven preform has stable quality.

[0024] The present invention weaves an orthogonal three-dimensional woven preform with a near-net-shape shape, while maintaining the continuity and integrity of the component's internal fiber structure. This reduces component manufacturing costs by reducing blanking time (preform RTM preparation time is 30 minutes, while layup RTM requires 2-3 hours), laying steps, and the use of a non-autoclave process. It also improves the component's resistance to delamination and damage tolerance through the integrated internal fiber structure. The process for producing the bifurcated orthogonal three-dimensional woven preform is relatively simple, and the existing machinery has a high degree of automation, effectively improving production efficiency and reducing production costs.

[0025] As a preferred solution, the present invention significantly improves the mechanical properties of the structure such as tension and compression outside the surface by designing and weaving the weft yarn path in the bifurcated orthogonal three-dimensional woven preform, and improves the mechanical properties of the structure in various directions such as axial and lateral directions. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram of a 1-2 bifurcation structure without crossover;

[0027] Figure 2 for Figure 1 Distribution map of possible weft yarn paths;

[0028] Figure 3 The preform test piece prepared in Example 1;

[0029] Figure 4 This is a schematic diagram of the 2-1-2 bifurcation structure;

[0030] Figure 5 It is a schematic diagram of the 2-2 bifurcation structure;

[0031] Figure 6 Schematic diagram of enhancing lateral performance by weft yarn distribution in a 2-2 bifurcated structure;

[0032] Figure 7 The preform test piece prepared in Example 2;

[0033] Figure 8 It is a schematic diagram of the 3-2 bifurcation structure;

[0034] Figure 9Schematic diagram of the local bifurcation structure;

[0035] Figure 10 Schematic diagram of the weaving of the bifurcation area of ​​the 1-3 bifurcation structure;

[0036] Figure 11 for Figure 2 8 is a schematic diagram of the weaving process of the weft yarn path;

[0037] Figure 12 It is a schematic diagram of the 1-3 bifurcation structure;

[0038] Figure 13 This is a schematic diagram of the vacuum infusion molding equipment;

[0039] Figure 14 Schematic diagram of the weaving process of the bifurcation area in Example 3. DETAILED DESCRIPTION

[0040] The present invention provides a weaving method for an orthogonal three-dimensional woven preform containing bifurcations, comprising the following steps:

[0041] (1) setting weaving parameters according to the geometric dimensions of the orthogonal three-dimensional woven preform; the weaving parameters include the number of warp yarn layers, the warp yarn density, the number of weft yarn layers, and the weft yarn density;

[0042] (2) setting a bifurcation mode and a bifurcation position according to the geometric dimensions of the orthogonal three-dimensional woven preform in step (1) and the mechanical performance requirements of the composite material structural component, and determining a bifurcation pattern of the orthogonal three-dimensional woven preform;

[0043] (3) designing a weft yarn path according to the conditions set in steps (1) and (2) to obtain a design scheme for an orthogonal three-dimensional woven preform bifurcated structure;

[0044] (4) According to the design scheme described in step (3), three-dimensional weaving technology is used for weaving to obtain an orthogonal three-dimensional woven preform containing bifurcations.

[0045] The present invention sets weaving parameters based on the geometric dimensions of an orthogonal three-dimensional woven preform. In the present invention, the weaving parameters include the number of warp yarn layers, warp yarn density, weft yarn layer number, and weft yarn density. By designing the geometric dimensions and weaving parameters of the orthogonal three-dimensional woven preform, the present invention can control the overall thickness of the preform.

[0046] In the present invention, when a region of an orthogonal three-dimensional woven preform is reinforced separately in the thickness direction with different normal yarns, rather than using normal yarns through the thickness to interlock the entire preform, a localized unreinforced plane is formed between the yarn layers, on which the preform can be unfolded to form a bifurcation.

[0047] In the present invention, the number of warp yarn layers is The orthogonal three-dimensional woven preform is divided into m warp yarn layers The branches of m-branch preform are obtained;

[0048] For the bifurcation-free region, the number of warp yarn layers of the orthogonal 3D woven preform and number of weft yarn layers The relationship is

[0049] For the m-bifurcation region, the sum of the weft yarn layers of the orthogonal three-dimensional woven preform is The number of weft yarns in each branch is

[0050] In the present invention, the number of warp yarn layers is mainly limited by the performance of the loom, and the number of warp yarn layers is preferably ≥3, and more preferably 20 to 24. The subscript 0 in represents the original state, and the superscript j represents the warp yarn. In the present invention, the total number of warp yarn layers is a constant, and the subsequent "fork" only involves the allocation of the number of warp yarn layers, and does not generate new warp yarn layers.

[0051] In the present invention, the The subscript i indicates the “i”-th branch; the whole number indicates how many warp yarn layers there are in the “i”-th branch.

[0052] In the present invention, the The subscript 0 in represents the original state, and the superscript w represents the weft yarn.

[0053] The present invention sets the bifurcation method and bifurcation position based on the geometric dimensions of the orthogonal three-dimensional woven preform and the mechanical performance requirements of the composite structural component, thereby determining the bifurcation pattern of the orthogonal three-dimensional woven preform. In the present invention, the composite structural component refers to the composite material obtained by molding the orthogonal three-dimensional woven preform. In the present invention, the designed bifurcation position includes the starting position and starting number of layers of the bifurcation.

[0054] In the present invention, it is preferred to control the number of warp yarn layers in each branch according to the design thickness of each branch after the m bifurcation. The thickness of the branch is controlled; and the starting number of layers is determined according to the position corresponding to the required number of layers so as to increase the weft yarn two-ply at the starting number of layers.

[0055] The present invention designs the weft yarn path based on the above-mentioned conditions to obtain a design scheme for the bifurcated structure of the orthogonal three-dimensional woven preform. By designing the weft yarn path, the present invention controls the connection form of the bifurcated position and the out-of-plane and lateral mechanical properties of the bifurcated structure.

[0056] In the present invention, the bifurcated structure preferably includes a 1-m bifurcated structure, an mm bifurcated structure, an m-1-m bifurcated structure, a k bifurcated-m bifurcated structure or a local bifurcated structure. In the present invention, the 1-m bifurcated structure preferably includes a 1-2 bifurcated structure or a 1-3 bifurcated structure; the 1-2 bifurcated structure can be pre-formed and expanded into a "T" type or a "Y" type structure. In the present invention, the mm bifurcated structure preferably includes a 2-2 bifurcated structure; the m-1-m bifurcated structure preferably includes a 2-1-2 bifurcated structure; the mm bifurcated structure or the m-1-m bifurcated structure can be pre-formed and expanded into an "I" type, "H" type, "K" type or "π" type structure. In the present invention, the k bifurcated-m bifurcated structure preferably includes a 3-2 bifurcated structure; the k bifurcated-m bifurcated structure can be pre-formed and expanded into an "I" type or "H" type structure.

[0057] As an embodiment of the present invention, Figure 1 This is a schematic diagram of a 1-2 bifurcation structure without crossover. Figure 1 In the center, 1 is the weft, 2 is the warp, and 3 is the two-ply weft. The left side shows the bifurcation area 1, and the right side shows the two branches of the bifurcation area 2. Sections AA and BB show the bifurcation areas 1 and 2, respectively. 4 is the weft, 5 is the two-ply weft, 6 is the warp, and 7 is the z-direction yarn. The 1-2 bifurcation structure can be preformed to expand into a T- or Y-shaped configuration.

[0058] Figure 2 for Figure 1 The possible weft yarn path distribution and branch thickness control can be realized by designing the weft yarn path to further control the mechanical properties of the structure, and the proportion of each branch can be further adjusted by designing the number of bifurcation starting layers. Figure 2 Figure 8 shows a typical cross arrangement, Figure 9 shows a typical winding arrangement; Figure 10 shows the design method when the branch thickness is different. Figure 2 The weft yarns are randomly distributed and can be further designed according to actual needs.

[0059] As an embodiment of the present invention, Figure 12 Schematic diagram of the 1-3 bifurcation structure.

[0060] As an embodiment of the present invention, Figure 4 This is a schematic diagram of the 2-1-2 bifurcation structure. Figure 4 11 and 13 are two fork regions, and 12 is a single fork region. Depending on the length of the single fork region and the length of the two fork regions, the structure can be pre-formed and expanded into an "I" type, "H" type, "K" type, or "π" type.

[0061] As an embodiment of the present invention, Figure 5 This is a schematic diagram of the 2-2 bifurcation structure. Figure 514 and 15 are two bifurcation areas, the middle of the bifurcation areas on the left and right sides is one bifurcation area, and 16 is the unfolded weft yarn (warp yarn is omitted).

[0062] As an embodiment of the present invention, Figure 6 Schematic diagram of 2-2 bifurcated structure, with weft yarn distribution to enhance lateral performance. Figure 6 If there are further requirements for lateral performance, the weft yarn path distribution can be designed so that there are connected weft yarns between adjacent branches. 17 is a preferred weft yarn distribution method, and 18 is the pre-formed and expanded weft yarn.

[0063] As an embodiment of the present invention, Figure 8 This is a schematic diagram of the 3-2 bifurcation structure. Figure 8 Reference numeral 19 represents a two-ply weft yarn, and reference 20 represents the weft yarn path after preforming and unfolding. The preform, after preforming and unfolding, forms a "large" structure. Further horizontally unfolding the left branch creates a horizontally reinforced "T" structure. Mirroring this structure creates "I" and "H" structures.

[0064] As an embodiment of the present invention, Figure 9 is a schematic diagram of the local bifurcation structure. Figure 9 21 is the weft yarn two-ply at the bifurcation thickness, 22 is the cutting position diagram, and 23 is the pre-formed and unfolded stiffener. Combined with appropriate cutting, part of the thickness of the plate can be sacrificed to produce a stiffened plate.

[0065] The present invention utilizes three-dimensional weaving technology to produce an orthogonal three-dimensional woven preform containing bifurcations. In the present invention, the weaving is preferably performed on a loom, more preferably a jacquard loom. The present invention preferably sequentially raises the warp yarns above the target weft yarn position from bottom to top, and then sequentially inserts the weft yarns.

[0066] As an embodiment of the present invention, Figure 10 This is a schematic diagram of the bifurcation weaving of the 1-3 bifurcation structure. Figure 10 28 is a weft weaving method for three bifurcated areas, 29 is a weft weaving method for one bifurcated area, 27 is a two-ply weft, the square shown in 25 represents the warp yarn perpendicular to the paper direction, the horizontal line represents that the warp yarn is not lifted, the upward arrow shown in 26 represents that the warp yarn is lifted in this step, and 24 represents the weft yarn.

[0067] As an embodiment of the present invention, Figure 11 for Figure 2 8 shows a schematic diagram of the weaving process of the weft yarn path, where weft yarns are added from bottom to top. Figure 11 On the left side, lift the warp yarn above the target weft yarn position, and Figure 11On the right side, lift the warp yarn above the position of the target weft yarn and insert the weft yarn. The process is repeated.

[0068] The present invention provides an orthogonal three-dimensional woven preform containing bifurcations obtained by the weaving method described in the above technical solution.

[0069] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions of the present invention. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0070] Example 1

[0071] 1-2 fork structure: Figure 1 This is a schematic diagram of a 1-2 bifurcation structure without crossover. Figure 1 In the center, 1 is the weft, 2 is the warp, and 3 is the two-ply weft. The left side is the bifurcation region 1, and the right side is the two branches of the bifurcation region 2. Sections AA and BB are cross-sections of the bifurcation region 1 and 2, respectively. 4 is the weft, 5 is the two-ply weft, 6 is the warp, and 7 is the z-direction yarn.

[0072] Overall parameters: 1 bifurcation area ( Figure 1 The left side) thickness is 4mm, 2 bifurcation areas ( Figure 1 The thicknesses of the right side are 2mm and 2mm respectively;

[0073] Weaving parameters:

[0074] The warp yarn in the bifurcation region has six layers, each containing 12k filaments (Toray T700-12k). The weft yarn has seven layers, each containing 12k filaments (Toray T700-12k). The third layer is two-ply (24k filaments total). The z-direction yarn has 12k filaments (Toray T700-12k). The warp yarn density is 3.33 strands / cm, and the weft yarn density is 2.22 strands / cm.

[0075] The 2-fork area has 3 layers in total, and the number of monofilament yarns in each layer is 24k (Toray T700-24k); the weft yarn has 4 layers in total, and the number of monofilament yarns in each layer is 12k (Toray T700-12k); the warp yarn density is 1.67 strands / cm, and the weft yarn density is 2.22 strands / cm.

[0076] Design of weft yarn path in bifurcation area: Figure 1 The ones shown do not cross, Figure 2 There are three options shown: cross, cross winding, and arbitrary scheme (the weft yarn path can be designed arbitrarily according to needs). Figure 11 Schematic diagram of the cross-region weaving process of Example 1.

[0077] The molding process uses vacuum infusion, such as Figure 13 As shown, (I) preheat the mold and resin system (brand EpoTech-4360A / B) at 50°C for 2h until the temperature of the mold and resin is uniform; (II) connect the liquid storage bottle, mold, resin storage tank and vacuum pump, and check the air tightness; (III) mix the resin components, vacuum defoam, and pour into the resin storage tank; (IV) close the feed valve, open the vacuum pump and the overflow valve until the air pressure in the mold is less than 50kPa; (V) slowly open the feed valve and inject resin for 3min. When there are no obvious bubbles at the overflow, close the feed valve first and then the overflow valve; (VI) transfer the mold after resin infusion to an oven and heat at 100°C for 2h to obtain the following Figure 3 The properties of the test pieces prepared in this embodiment are shown in Table 1. The reference test piece in Table 1 is a ply, and the results in the table are normalized, with one significant figure retained.

[0078] Table 1 Performance of the test piece of Example 1

[0079]

[0080] As can be seen from Table 1, under tensile load, the bifurcated orthogonal three-dimensional woven preform prepared by the present invention has a significant advantage in maximum load and is superior to the reference in stiffness under the same molding conditions. Different weft yarn paths significantly affect the maximum load. The optimal cross-wrapped structure in the test case increases the maximum load by 530% and the stiffness by 40% compared to the reference laminate test piece.

[0081] Example 2

[0082] 2-1-2 fork structure: Figure 4 This is a schematic diagram of the 2-1-2 bifurcation structure. Figure 4 11 and 13 are two-fork areas, and 12 is a single-fork area.

[0083] The specific weaving parameters are:

[0084] 1 bifurcation area ( Figure 4 The warp yarn has 6 layers, each containing 12k filaments (Toray T700-12k). The weft yarn has 7 layers, each containing 12k filaments (Toray T700-12k). The third layer is two-ply (24k filaments total). The z-direction yarn has 12k filaments (Toray T700-12k). The warp yarn density in the bifurcation region is 3.33 strands / cm, and the weft yarn density is 2.22 strands / cm. There are 38 warp yarn groups and 5 weft yarn groups in the bifurcation region.

[0085] 2 bifurcation area ( Figure 4 In 11 and 13, the warp yarns consist of three layers, each containing 24k filaments (Toray T700-24k). The weft yarns consist of four layers, each containing 12k filaments (Toray T700-12k). The warp yarn density in the bifurcation region is 1.67 strands / cm, and the weft yarn density is 2.22 strands / cm. There are eight warp yarn groups and five weft yarn groups in the bifurcation region.

[0086] Design of weft yarn path in bifurcation area: Figure 1 The ones shown do not cross, Figure 2 From left to right, there are three options: cross, cross winding, and arbitrary scheme (the weft yarn path can be designed arbitrarily according to needs). Figure 11 This is a schematic diagram of the weaving process of the cross region 1-2 on one side of Example 2, which is mirrored to form the other side 2-1.

[0087] The molding process is the same as in Example 1, and the Figure 7 The properties of the test pieces prepared in this embodiment are shown in Table 2. The reference test piece in Table 2 is a ply.

[0088] Table 2 Performance of the test piece of Example 2

[0089]

[0090] It can be seen from Table 2 that in the tensile test of the "I-shaped structure" manufactured by the 2-1-2 bifurcated preform, the orthogonal three-dimensional woven preform with bifurcations prepared by the present invention has an obvious advantage in the maximum load of the test piece manufactured after the same molding process.

[0091] Example 3

[0092] 3-2 fork structure: Figure 8 This is a schematic diagram of the 3-2 bifurcation structure. Figure 8 Reference numeral 19 denotes a two-ply weft yarn, and reference numeral 20 denotes a weft yarn path after preforming and unfolding.

[0093] The specific weaving parameters are:

[0094] 2 bifurcation area ( Figure 8 (right side) The warp yarn has 6 layers, each containing 12k filaments (Toray T700-12k). The weft yarn has 8 layers, each containing 12k filaments (Toray T700-12k). The sixth layer is two-ply (24k filaments total). There is no warp yarn between the third and fourth weft layers. The z-direction yarn contains 12k filaments (Toray T700-12k). The warp yarn density in the bifurcation region is 3.33 strands / cm, and the weft yarn density is 2.22 strands / cm.

[0095] 3 bifurcation area ( Figure 8 (Left side) The warp yarn has two layers, each containing 24k filaments (Toray T700-24k); the weft yarn has three layers, each containing 12k filaments (Toray T700-12k). The warp yarn density in the three-pronged region is 1.67 strands / cm, and the weft yarn density is 2.22 strands / cm.

[0096] Figure 14 Schematic diagram of the weaving process of the bifurcation area in Example 3.

[0097] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for weaving a bifurcated orthogonal three-dimensional woven preform, comprising the following steps: (1) Setting weaving parameters according to the geometric dimensions of the orthogonal three-dimensional woven preform; The weaving parameters include the number of warp yarn layers, the warp yarn density, the number of weft yarn layers and the weft yarn density; the step (1) includes: The number of warp yarn layers is The orthogonal three-dimensional woven preform is divided into m warp yarn layers The branches of m-branch preform are obtained; described The subscript 0 in the code indicates the original state, and the superscript j indicates the warp yarn. The subscript i in the middle indicates the "i"th branch; the whole indicates how many warp yarn layers there are in the "i"th branch; For the bifurcation-free region, the number of warp yarn layers of the orthogonal 3D woven preform and number of weft yarn layers The relationship is described The subscript 0 in the is the original state, and the superscript w is the weft yarn; For the m-bifurcation region, the sum of the weft yarn layers of the orthogonal three-dimensional woven preform is The number of weft yarns in each branch is (2) According to the geometric dimensions of the orthogonal three-dimensional woven preform in step (1) and the mechanical performance requirements of the composite material structure, the bifurcation mode and bifurcation position are set to determine the bifurcation pattern of the orthogonal three-dimensional woven preform; said step (2) comprises: according to the design thickness of each branch after the m bifurcation, controlling the number of warp yarn layers in the branch Control the thickness of the branch; and determine the starting number of layers according to the position corresponding to the required number of layers to increase the weft yarn two-ply at the starting number of layers; (3) designing a weft yarn path according to the conditions set in steps (1) and (2) to obtain a design scheme for an orthogonal three-dimensional woven preform bifurcated structure; (4) According to the design scheme described in step (3), three-dimensional weaving technology is used for weaving to obtain an orthogonal three-dimensional woven preform containing bifurcations.

2. The weaving method according to claim 1, characterized in that The bifurcated structure includes a 1-m bifurcated structure, an mm bifurcated structure, an m-1-m bifurcated structure, a k-bifurcated-m bifurcated structure or a local bifurcated structure.

3. The weaving method according to claim 2, characterized in that The 1-m bifurcation structure includes a 1-2 bifurcation structure or a 1-3 bifurcation structure.

4. The weaving method according to claim 2, characterized in that The mm bifurcated structure includes a 2-2 bifurcated structure.

5. The weaving method according to claim 2, characterized in that The m-1-m bifurcation structure includes a 2-1-2 bifurcation structure.

6. The weaving method according to claim 2, characterized in that The k-fork-m-fork structure includes a 3-2-fork structure.

7. The weaving method according to claim 1, characterized in that The weaving comprises: sequentially lifting the warp yarns above the position of the target weft yarn in order from bottom to top, and sequentially inserting the weft yarns.

8. An orthogonal three-dimensional woven preform containing bifurcations obtained by the weaving method according to any one of claims 1 to 7.

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