A method and apparatus for preform composite molding with in-plane shear deformation

Abstract

This invention provides a method and apparatus for preform composite molding with in-plane shear deformation. The apparatus includes a deformation component and a limiting component. The deformation component includes clamping fixtures, fasteners, and fixing members. Each clamping fixture consists of four clamping frames, which are connected end-to-end by fasteners to form a quadrilateral. The clamping fixtures are used to clamp and deform the preform to be deformed. The limiting component includes four thickness-limiting washers, a first fixing strip, and a fixing base plate. The first fixing strip is used to fix the deformed preform. Two first fixing strips are located on the upper and lower sides of the deformation component and are parallel to each other. The two ends of each fixing strip are connected to the deformation component by two fasteners at opposite corners in the clamping fixture. The fixing base plate is used to press the surface of the deformed preform. The preform composite molding apparatus in this solution can realize the preparation of preforms reinforced with in-plane shear deformation.

Description

Technical Field

[0001] This invention relates to the field of composite material molding technology, and in particular to a method and apparatus for preform composite molding with in-plane shear deformation. Background Technology

[0002] Composite materials possess excellent comprehensive properties and hold a strategic position in the new materials industry. Among them, three-dimensional woven preforms can be used to prepare irregularly shaped composite material components of different sizes and complex shapes in near-net-shape form, realizing the integrated design and manufacturing of composite materials.

[0003] As a reinforcing structure for composite materials, precast structures often require deformation to meet the structural shape of composite components. This process involves tensile, compressive, shear, and bending deformations of the precast structure. In related technologies, shear tests or off-axis tensile tests are commonly used to study the shear characteristics of precast structures. For example, Chinese patents CN107084874B, CN208313705U, and CN 214224754U, among others, improve the frame clamps to study the shear characteristics of precast structures.

[0004] The purpose of preform deformation is to achieve near-net-shape forming of composite products. Since the deformed preform, as a reinforcing phase in composite components, inevitably affects the mechanical properties of the components, the impact of preform deformation on the composite material should be considered when designing composite products. However, existing preform shear deformation components can only study the shear properties of the preform, and cannot study the impact of preform shear deformation on the mechanical properties of the composite material.

[0005] Therefore, based on the above problems, there is an urgent need for a preform composite molding method and apparatus with in-plane shear deformation. Summary of the Invention

[0006] To study the influence of preform shear deformation on the mechanical properties of composite materials, this invention provides a preform composite molding method and apparatus with in-plane shear deformation.

[0007] In a first aspect, embodiments of the present invention provide a preform composite molding apparatus with in-plane shear deformation, comprising: a deformation component and a limiting component, wherein:

[0008] The deformation assembly includes two sets of clamping fixtures, four fasteners, and several fixing members. Each set of clamping fixtures consists of four clamping frames, and each clamping frame is connected end to end by fasteners to form a quadrilateral. The two sets of clamping fixtures are located on the upper and lower sides of the preform to be deformed, respectively, and the four clamping frames of each set of clamping fixtures correspond one-to-one. The clamping fixtures are used to clamp and deform the preform to be deformed. The fixing members are located on each clamping frame and are used to fix the preform to be deformed to the deformation assembly together.

[0009] The limiting component includes four thickness-limiting washers, two first fixing strips, and two fixing base plates. The thickness-limiting washers are located between two sets of clamping fixtures and are connected to each fastener. The thickness-limiting washers are used to limit the thickness of the preformed composite material. The fixing base plates are placed on the upper and lower surfaces of the deformed preform to press the surfaces of the deformed preform together. The first fixing strips are used to fix the deformed preform. The two first fixing strips are located on the upper and lower sides of the fixing base plate and are parallel to each other. The two ends of each first fixing strip are connected to the deformation component through two fasteners at opposite corners in the clamping frame.

[0010] Preferably, the length of each clamping frame is equal, so that the clamping fixture forms a square.

[0011] Preferably, each clamping frame consists of a clamping area and overlapping areas at both ends of the clamping area, wherein the thickness of the overlapping areas is half the thickness of the clamping area.

[0012] Preferably, each overlapping area is provided with a first connecting hole, through which the fastener passes to connect the two sets of clamping fixtures together.

[0013] Preferably, the length of the clamping area is determined by the following formula:

[0014]

[0015] In the formula, L d L is the length of the clamping area. p W0 is the distance between the centers of the two first connecting holes in the clamping frame, and γ is the width of each clamping frame. m Δ1 is the maximum shear deformation angle of the preform to be deformed, and Δ1 is the first allowance.

[0016] Preferably, each clamping frame has a plurality of second connecting holes distributed on its clamping area, the second connecting holes being used to accommodate the fixing member.

[0017] Preferably, the fixed base plate has the same shape as the deformation zone of the deformed precast body; wherein, the side length of the fixed base plate is determined by the following formula:

[0018]

[0019] In the formula, L m L is the side length of the fixed base plate. p γ is the distance between the centers of the two first connecting holes in each clamping frame, γ is the shear deformation angle of the preform to be deformed, and Δ2 is the second allowance.

[0020] Preferably, the limiting component further includes two second fixing strips; the two second fixing strips are respectively located on the upper and lower sides of the deformable component, the second fixing strips located on the same side are perpendicular to the first fixing strip, and the two ends of each second fixing strip are respectively connected to the deformable component by fasteners at two other opposite corners in the clamping frame.

[0021] Preferably, each of the first fixing bars has a plurality of third connecting holes at both ends, and each of the second fixing bars has a plurality of fourth connecting holes at both ends. The fasteners pass through the third connecting holes and the fourth connecting holes respectively, so that the deformable component is connected to the first fixing bar and the second fixing bar respectively.

[0022] Preferably, the length of the second fixing strip is greater than the length of the first fixing strip.

[0023] Preferably, the distance between the centers of adjacent third connecting holes and the distance between the centers of adjacent fourth connecting holes are determined by the following formula:

[0024] L c =2L p sin(γ / 2)

[0025] L c =2L p cos(γ / 2)

[0026] In the formula, L c L is the distance between the centers of adjacent third connecting holes. c ' is the distance between the centers of the adjacent fourth connecting holes, L p The distance between the centers of the two first connecting holes in the clamping frame is γ, and the shear deformation angle of the preform to be deformed is γ.

[0027] Preferably, the preform to be deformed includes a deformation zone and a clamping zone, and the deformation zone and the clamping zone together form a cross shape.

[0028] More preferably, the length of the clamping area of ​​the preform to be deformed is determined by the following formula:

[0029]

[0030] In the formula, L yL is the length of the clamping area of ​​the preform to be deformed. p γ is the distance between the centers of the two first connecting holes in the two overlapping areas on each clamping frame, γ is the shear deformation angle of the preform to be deformed, and Δ3 is the third allowance.

[0031] In a second aspect, embodiments of the present invention provide a method for preparing composite materials using a preform composite molding apparatus with in-plane shear deformation as described in any of the first aspects above, the method comprising:

[0032] (1) Assemble the preform to be deformed into the deformation assembly, and place the thickness limiting washer between the two sets of clamping fixtures, and use the clamping fixtures to clamp the preform to be deformed;

[0033] (2) Fix one of the fasteners in the deformation component to the corner point, and move the fastener in the deformation component to the corner point opposite to it to a preset displacement so that the preform to be deformed undergoes shear deformation.

[0034] (3) Place a fixed base plate on the upper and lower surfaces of the deformed precast body, and use fasteners to set the first fixing strip on the upper and lower sides of the fixed base plate to fix the deformed precast body.

[0035] (4) Place the preform from step (3) into a vacuum bag and use the vacuum bag pressure resin flow molding process to composite mold the preform to obtain a composite material.

[0036] Compared with the prior art, the present invention has at least the following beneficial effects:

[0037] This invention integrates preform shear deformation and composite molding, designing a device that combines these two processes. The device comprises a deformation component and a limiting component. The deformation component clamps the preform to be deformed and induces shear deformation. After shear deformation, limiting components are placed on the upper and lower sides of the deformation component to fix the deformed preform's shape. Finally, a vacuum bag-pressed resin flow molding process is used to mold the composite material. Therefore, the molding device of this invention can simultaneously achieve preform shear deformation, maintain the preform's state after shear deformation, and composite molding of the preform under shear deformation conditions. This enables the preparation of preforms reinforced with in-plane shear deformation. The device has a simple structure and high versatility, suitable for preparing preforms with different thicknesses and various shear deformation angles, thereby facilitating the study of the mechanical properties of preform-reinforced composite materials under shear deformation conditions. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a schematic diagram of the deformed structure of a preform composite molding device with in-plane shear deformation according to an embodiment of the present invention.

[0040] Figure 2 This is a schematic diagram of the deformed structure of a preform composite molding device with in-plane shear deformation according to another embodiment of the present invention;

[0041] Figure 3 This is an initial structural schematic diagram of a preform composite molding device with in-plane shear deformation according to an embodiment of the present invention.

[0042] Figure 4 This is a schematic diagram of the deformed structure of a preform composite molding device with in-plane shear deformation according to another embodiment of the present invention;

[0043] Figure 5 This is a top view schematic diagram of the deformed structure of a preform composite molding device with in-plane shear deformation according to another embodiment of the present invention.

[0044] Figure 6 This is a schematic cross-sectional view of the clamping frame in a preform composite molding device with in-plane shear deformation according to an embodiment of the present invention.

[0045] Figure 7 This is a schematic diagram of the structure of a preform provided in an embodiment of the present invention;

[0046] Figure 8 This is a schematic diagram of the cutting of the composite material prepared by the preform shearing device in the embodiment of the present invention;

[0047] In the diagram: 100-Deformation component, 200-Limiting component, 101-Clamping fixture, 102-Fastener, 103-Fixing component, 104-Clamping frame, 1031-Screw, 1032-Nut, 201-Thickness limiting washer, 202-First fixing strip, 203-Second fixing strip, 2021-Fixing groove, 1011-Clamping area, 1012-Overlapping area, 1013-First connecting hole, 1014-Second connecting hole, 1015-Third connecting hole, 1016-Fourth connecting hole, 400-Fixing base plate, 300-Precast body, 301-Deformation area, 302-Clamping area, 303-Cutting line. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0049] Based on one or more of the above issues, such as Figure 1 and Figure 2 As shown, this embodiment of the invention provides a preform composite molding device with in-plane shear deformation. The device includes a deformation component 100 and a limiting component 200, wherein:

[0050] The deformation assembly 100 includes two sets of clamping clamps 101, four fasteners 102, and several fixing members 103. The clamping clamps 101 are composed of four clamping frames 104, which are connected end to end by the fasteners 102 to form a quadrilateral. The two sets of clamping clamps 101 are located on the upper and lower sides of the preform 300 to be deformed, and the four clamping frames 104 of the two sets of clamping clamps 101 correspond one-to-one. The clamping clamps 101 are used to clamp and deform the preform 300 to be deformed. The fixing members 103 are located on each clamping frame 104 and are used to fix the preform 300 to be deformed together with the deformation assembly.

[0051] The limiting component includes four thickness limiting washers 201, two first fixing strips 202, and two fixing base plates 400. The thickness limiting washers 201 are located between two sets of clamping clamps 101 and are respectively connected to fasteners 102. The thickness limiting washers 201 are used to limit the thickness of the preform 300 forming composite material. The fixing base plates 400 are placed on the upper and lower surfaces of the deformed preform 300 and are used to press the surfaces of the deformed preform 300. The first fixing strips 202 are used to fix the deformed component 100. The two first fixing strips 202 are located on the upper and lower sides of the fixing base plate 400 respectively and are parallel to each other. The two ends of the first fixing strips 202 are connected to the deformed component 100 through fasteners 102 at two opposite corner positions in the clamping clamps 101.

[0052] like Figure 1 and Figure 2As shown, in this embodiment of the invention, a device integrating the shear deformation and composite molding of the preform 300 is designed by associating the shear deformation and composite molding of the preform 300 together. The device consists of a deformation component and a limiting component. The deformation component is used to clamp the preform 300 to be deformed and cause it to undergo shear deformation. The preform 300 is connected and fixed to the deformation component 100 by the fixing component 103. This not only reduces the damage to the yarn during the clamping of the preform 300 and reduces the impact of the clamping boundary on the deformation area 301 of the preform, but also facilitates the demolding of the subsequent molded composite material. The deformation component completes the shear deformation of the preform 300. The position of the deformation component is limited by the simple cooperation between the thickness limiting washer 201, the fixed base plate 400 and the first fixing strip 202. This simultaneously achieves precise control of the shear deformation of the preform 300, maintenance of the shear deformation state of the preform 300, control of the molding thickness of the composite material, and coordinated control of the surface quality of the molded composite material. Finally, the preform 300 composite material is molded using a vacuum bag pressure resin guiding molding process. Therefore, the molding device in this invention can simultaneously realize the shear deformation of the preform 300, the maintenance of the state of the preform 300 after shear deformation, and the composite molding of the preform 300 under shear deformation, thereby realizing the preparation of preform composite material test specimens with in-plane shear deformation, which can be used for the study of the mechanical properties of preform reinforced composite materials under shear deformation.

[0053] In this embodiment of the invention, the clamping frames 104 have the same specifications, and after the clamping frames 104 are connected end to end by fasteners 102, the initial shape of the formed deformable component 100 is square (e.g., ...). Figure 2 As shown), but during the subsequent shear deformation process, the shape of the deformation component 100 is changed by moving the fastener 102, for example, transforming it into a rhombus (as shown). Figure 1 (as shown); Thus, the deformation component 100 in this embodiment of the invention can cause the preform 300 to undergo shear deformation within a range of 0-60°.

[0054] In some implementations, such as Figure 3 and Figure 4 As shown, each clamping frame 104 is composed of a clamping area 1011 and overlapping areas 1012 located at both ends of the clamping area 1011. The thickness of the overlapping area 1012 is half the thickness of the clamping area 1011. Each overlapping area 1012 is provided with a first connecting hole 1013. The fastener 102 passes through the first connecting hole 1013 to connect the upper and lower sets of clamping clamps 101 together.

[0055] In this embodiment of the invention, by Figures 1 to 5As shown, each clamping frame 104 is the same size and is composed of a clamping area 1011 and an overlapping area 1012. The overlapping areas 1012 are located at both ends of the clamping area 1011. The clamping area 1011 is used to clamp the preform 300. Each overlapping area 1012 is provided with a first connecting hole 1013. Fasteners 102 pass through the first connecting holes 1013 on the overlapping area 1012 to connect the clamping frames 104 together, so that each set of clamping fixtures 101 is quadrilateral. The clamping areas 1011 and overlapping areas 1012 of each clamping frame 104 in the upper and lower sets of clamping fixtures 101 correspond one-to-one. The thickness of the overlapping area 1012 is half the thickness of the clamping area 1011, so that the upper and lower surfaces of the clamping areas 1011 of the connected clamping frames 104 in the clamping fixture 101 are all on the same plane.

[0056] It should be noted that the fastener 102 can be composed of any component with a connecting function. In this embodiment of the invention, the fastener 102 can specifically be composed of a screw 1031 and a nut 1032 (e.g., Figures 1 to 3 As shown in the figure, during use, after the screw 1031 is passed through the first connecting hole 1013 on the overlapping area 1012 in the clamping frame 104, the upper and lower clamping clamps 101 can be fixedly connected by tightening the nut 1032.

[0057] In some implementations, such as Figure 6 As shown, the length of the clamping area 1011 is determined by the following formula:

[0058]

[0059] In the formula, L d L is the length of the clamping area. p W0 is the distance between the centers of the two first connecting holes in the clamping frame, and γ is the width of each clamping frame. m Let Δ1 be the maximum shear deformation angle of the preform to be deformed, and let Δ1 be the first allowance. Using the above formula, the clamping frame 104 is determined, enabling the deformation component 100 to drive the preform 300 to undergo a deformation not exceeding γ. m The shear deformation effectively avoids collision interference between the clamping frame 104 during the deformation process.

[0060] In some embodiments, a plurality of second connecting holes 1014 are distributed on the clamping area 1011 of the clamping frame 104, and the second connecting holes 1014 are used to accommodate the fastener 103.

[0061] In this embodiment of the invention, reference Figure 2 and 3By uniformly arranging a plurality of second connecting holes 1014 on the clamping area 1011 of each clamping frame 104, and the second connecting holes 1014 on the clamping area 1011 of each clamping frame 104 corresponding one-to-one, when the preform 300 to be deformed is placed between the clamping frames 104 of the upper and lower clamping fixtures 101, the fixing member 103 (e.g., a fixing nail) is passed through the second connecting holes 1014 in the clamping frame 104, thereby connecting the edge of the preform 300 to be deformed with the clamping of the deformation component. The frame 104 is fixedly connected together; thus, during the shearing deformation of the preform 300 using the deformation component 100, the fixing member 103 can drive the preform 300 to move with the clamping frame 104, thereby not only preventing the preform 300 from sliding in the clamping area 1011 and reducing yarn damage during the clamping process, but also reducing the impact on the boundary of the deformation area of ​​the preform 300 during the shearing deformation process. At the same time, it has the advantages of convenient operation and convenient demolding of composite materials.

[0062] In some implementations, such as Figure 2 As shown, the fixed base plate 400 has the same shape as the deformed precast body 300; wherein, the side length of the fixed base plate 400 is determined by the following formula:

[0063]

[0064] In the formula, L m L is the side length of the fixed base plate. p γ is the distance between the centers of the two first connecting holes in the clamping frame, γ is the shear deformation angle of the preform to be deformed, and Δ2 is the second allowance.

[0065] In embodiments of the present invention, such as Figure 2 As shown, after the preform 300 is sheared and deformed using the deformation component 100, two fixed base plates 400 can be set on the upper and lower surfaces of the deformed preform 300. The thickness of the fixed base plates 400 is the same as the thickness of the clamping area 1011 of the clamping frame 104. After the fixed base plates 400 are set on the upper and lower surfaces of the deformed preform 300, they are further coordinated with the two upper and lower first fixing strips 202. This not only helps to ensure that the preform 300 after shearing and deformation has a good surface condition, but also enables precise control of the shearing deformation of the preform 300.

[0066] Meanwhile, the shape of the fixed base plate 400 should be the same as the shape of the deformed preform 300. For example, if the deformed preform 300 is rhomboid, then the shapes of the two fixed base plates 400 should also be rhomboid. The angle and side length of the fixed base plate 400 can be determined according to the shear deformation angle of the preform 300, the length of the clamping frame 104, and the angular relationship after shear deformation. In this way, after the preform 300 is subjected to different shear deformations by the deformation component 100, the position of the deformation component can be restricted by replacing the fixed base plate 400 with one that matches the deformation size, and further by the simple cooperation of the clamping frame 104 and the first fixing strip 202. This is conducive to simultaneously achieving precise control of the shear deformation of the preform 300, maintaining the shear deformation state of the preform 300, controlling the molding thickness of the preform 300 composite material, and controlling the surface quality of the composite material.

[0067] Meanwhile, it should be noted that in this embodiment of the invention, by setting the four corners of the fixed base plate 400 as chamfers and ensuring that the gap between the fixed base plate 400 and the clamping frame 104 does not exceed 0.5mm, and the radius of the chamfer can be, for example, 0.5-3mm, this not only facilitates the assembly of the fixed base plate 400, but also ensures that the size of the composite material specimen is maximized after demolding.

[0068] In some implementations, such as Figure 4 As shown, the limiting component also includes two second fixing bars 203; each pair of second fixing bars 203 is located on the upper and lower sides of the fixed base plate 400 respectively, and the second fixing bars 203 located on the same side are perpendicular to the first fixing bars 202. The two ends of each second fixing bar 203 are connected to the deformation component through two other fasteners 102 at opposite corners in the clamping fixture 101.

[0069] In embodiments of the present invention, such as Figures 2 to 4 As shown, since the deformation component 100 can transform the preform 300 from a square to a rhombus after shearing deformation, in order to keep the preform 300 in the sheared deformation state, in this embodiment of the invention, two second fixing strips 203 are further provided. The first fixing strip 202 and the second fixing strip 203 cooperate with each other to limit the two fixing base plates 400 on the surface of the preform 300, thereby not only effectively maintaining the state of the preform 300 after shearing deformation, but also effectively preventing the four corners of the fixing base plates 400 from warping, which is conducive to ensuring that the composite material parts formed by the preform 300 after shearing deformation have uniform thickness.

[0070] In some embodiments, the length of the second fixing strip 203 is greater than the length of the first fixing strip 202.

[0071] In some implementations, such as Figure 4 As shown, each of the first fixing bars 202 has several third connecting holes 1015 at both ends, and each of the second fixing bars 203 has several fourth connecting holes 1016 at both ends. The fasteners 102 pass through the third connecting holes 1015 and the fourth connecting holes 1016 respectively, so that the deformable components are connected to the first fixing bars 202 and the second fixing bars 203 respectively.

[0072] In embodiments of the present invention, such as Figures 2 to 5 As shown, for example, the length of the second fixing strip 203 can be greater than the length of the first fixing strip 202, and a fixing groove 2021 can be further provided in the middle area of ​​the second fixing strip 203. The fixing groove 2021 is used to engage with the middle area of ​​the first fixing strip 202. After deformation, after placing the two fixing base plates 400 on the upper and lower surfaces of the deformed preform 300, the fasteners P' and Q' at opposite angles on the short diagonal can be passed through the third connecting holes 1015 at both ends of the first fixing strip 202, thereby fixing the first fixing strip 202 to the deformable component 100. The fasteners P and Q at opposite angles on the long diagonal can be passed through the fourth connecting holes 1016 at both ends of the second fixing strip 203, thereby further fixing the second fixing strip 203 to the deformable component 100.

[0073] In some implementations, such as Figure 4 As shown, the distance between the centers of adjacent third connecting holes 1015 and adjacent fourth connecting holes 1016 are determined by the following formulas:

[0074] L c =2L p sin(γ / 2)

[0075] L c =2L p cos(γ / 2)

[0076] In the formula, L c L is the distance between the centers of adjacent third connecting holes. c ' is the distance between the centers of the adjacent fourth connecting holes, L p The distance between the centers of the two first connecting holes in the clamping frame is γ, and the shear deformation angle of the preform to be deformed is γ.

[0077] In this embodiment of the invention, a plurality of third connecting holes 1015 that cooperate with fasteners 102 are further provided at both ends of the first fixing strip 202, and fourth connecting holes 1016 that cooperate with fasteners 102 are provided at both ends of the second fixing strip 203. The distance between the centers of adjacent third connecting holes 1015 and adjacent fourth connecting holes 1016 at both ends of the first fixing strip 202 and the second fixing strip 203 is determined by the above formula, so as to achieve the fixing of the shape of the preform 300 under different shear deformation angles.

[0078] In this embodiment of the invention, through the simple cooperation between the thickness limiting washer 201, the first fixing strip 202 and the second fixing strip 203 in the limiting component 200 and the fixing base plate 400, it is possible not only to restrict the position between the clamping fixtures 101 of the deformation component 100, thereby achieving precise control of the shear deformation of the preform 300, but also to maintain the state of the preform 300 after shear deformation, and to regulate the molding thickness and surface quality of the composite material.

[0079] In some implementations, such as Figure 7 As shown, the preform to be deformed 300 includes a deformation area 301 and a clamping area 302, which together form a cross shape;

[0080] The length of the clamping area of ​​the preform 300 to be deformed is determined by the following formula:

[0081]

[0082] In the formula, L y L is the length of the clamping area of ​​the preform to be deformed. p γ is the distance between the centers of the two first connecting holes in the two overlapping areas on each clamping frame, γ is the shear deformation angle of the preform to be deformed, and Δ3 is the third allowance.

[0083] In embodiments of the present invention, such as Figure 7 As shown, by setting the preform to be deformed 300 as a deformation area 301 and a clamping area 302, and the deformation area 301 and the clamping area 302 together make the preform to be deformed 300 cross-shaped, the preform to be deformed 300 and the deformation component 100 can have good matching.

[0084] It should be noted that, in the embodiments of the present invention, in the process of calculating the length of the clamping area 1011 of the clamping frame 104 and the length of the clamping area 302 of the preform to be deformed 300, a certain allowance is set respectively. The allowance can be no less than 2mm, which is beneficial to realize the flexible deformation of the deformation component 100.

[0085] This invention also provides a method for preparing composite materials using a preform composite molding apparatus with in-plane shear deformation according to any one of the preceding claims, the method comprising:

[0086] (1) Assemble the preform to be deformed into the deformation assembly, and place the thickness limiting washer between the upper and lower clamping fixtures, and use the clamping fixtures to clamp the preform to be deformed;

[0087] (2) Fix one of the fasteners in the deformation component to the corner point, and move the fastener in the deformation component to the corner point opposite to it to a preset displacement so that the preform to be deformed undergoes shear deformation.

[0088] (3) Place a fixed base plate on the upper and lower surfaces of the deformed preform, and use fasteners to set the first fixing strip on the upper and lower sides of the fixed base plate to fix the deformed components and the preform.

[0089] (4) Place the device assembled in step (3) into a vacuum bag and use the vacuum bag pressure resin flow molding process to composite mold the preform to obtain a composite material.

[0090] In embodiments of the present invention, such as Figures 2 to 5 As shown, when preparing composite materials using the aforementioned preform 300 composite molding device with in-plane shear deformation, specifically, firstly, the length of the clamping area 1011 of the clamping frame 104 can be determined according to the size of the preform 300 to be deformed and the preset shear deformation angle. Then, the clamping area 302 of the preform 300 to be deformed is clamped between the clamping frames 104 of the upper and lower clamping fixtures 101, and a thickness limiting washer 201 is placed between each clamping frame 104 of the upper and lower clamping fixtures 101. Then, a fastener 103 (such as a steel nail) is passed through the connecting hole on the clamping area 1011 of the clamping frame 104 to fix the preform 300 and the deformation component together. The screw 1031 of the fastener 102 (for example, a screw 1031 and a nut 1032) can be passed through... The first connecting hole 1013 of the clamping frame 104 is used for fixed connection. In order to facilitate shearing deformation, the fastener 102 in the deformation component is not fully tightened, and one corner of the deformation component (for example, corner point P) is fixed. The opposite corner point Q is moved to a preset displacement, so that the deformation component 100 undergoes diagonal displacement and drives the preform 300 to undergo shearing deformation. After the shearing deformation is completed, the fixed base plate 400 is placed on the upper and lower surfaces of the deformed preform 300, and the third connecting hole 1015 on the first fixing strip 202 and the second fixing strip 203 are passed through the fastener 102 screw 1031 at the opposite corner point. The first fixing strip and the second fixing strip are fixed with nuts 1032, thereby completing the fixation and retention of the shape of the deformed preform 300.

[0091] Furthermore, during the composite molding of preform 300, the aforementioned preform composite molding device with in-plane shear deformation (including preform 300) can be placed entirely in a vacuum bag, and the guide tubes can be placed on the outer sides of the two opposite sides of the preform composite molding device and closely attached to the preform 300. The composite material is prepared and molded using a unidirectional resin flow method. After curing and demolding, it is then processed as follows... Figure 8 The demolded material is cut along cutting line 303 as shown to obtain the composite material.

[0092] In some implementations, the preset displacement of the corner points is calculated using the following formula:

[0093] U = 2L p [cos(45°-γ / 2)-cos45°]

[0094] In the formula, U is the preset displacement of the diagonal corner point, γ is the shear deformation angle of the preform to be deformed, and L d The length of the clamping area is given. Using the above formula to determine the fastener displacement at the corner points facilitates precise control of the shear deformation of the preform.

[0095] It should be noted that, in this embodiment of the invention, in order to improve the molding quality of the composite material, a double vacuum bag molding process can also be used to cure and mold the composite material. The matrix resin can be selected according to actual needs, such as epoxy resin, phenolic resin or unsaturated resin, etc.

[0096] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0097] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing composite materials using a preform composite molding device with in-plane shear deformation, characterized in that, The method includes: (1) Assemble the preform to be deformed into the deformation assembly, and place the thickness limiting washer between the two sets of clamping fixtures, and use the clamping fixtures to clamp the preform to be deformed; (2) Fix the corner point corresponding to one of the fasteners in the deformation component, and move the fastener of the opposite corner point in the deformation component to the preset displacement so that the preform to be deformed undergoes shear deformation; (3) Place a fixed base plate on the upper and lower surfaces of the deformed precast body, and use fasteners to set the first fixing strip on the upper and lower sides of the fixed base plate to fix the deformed precast body. (4) Place the preform from step (3) in a vacuum bag and use the vacuum bag pressure resin flow molding process to composite mold the preform to obtain a composite material. The preform composite molding device with in-plane shear deformation includes a deformation component and a limiting component, wherein: The deformation assembly includes two sets of clamping fixtures, four fasteners, and several fixing members. Each set of clamping fixtures consists of four clamping frames, and each clamping frame is connected end to end by fasteners to form a quadrilateral. The two sets of clamping fixtures are located on the upper and lower sides of the preform to be deformed, respectively, and the four clamping frames of each set of clamping fixtures correspond one-to-one. The clamping fixtures are used to clamp and deform the preform to be deformed. The fixing members are located on each clamping frame and are used to fix the preform to be deformed to the deformation assembly together. The limiting component includes four thickness-limiting washers, two first fixing strips, and two fixing base plates. The thickness-limiting washers are located between two sets of clamping fixtures and are connected to each fastener. The thickness-limiting washers are used to limit the thickness of the preformed composite material. The fixing base plates are placed on the upper and lower surfaces of the deformed preform to press the surfaces of the deformed preform. The first fixing strips are used to fix the deformed preform. The two first fixing strips are located on the upper and lower sides of the fixing base plate and are parallel to each other. The two ends of each first fixing strip are connected to the deformation component through two fasteners at opposite corners in the clamping fixtures.

2. The method according to claim 1, characterized in that, Each clamping frame consists of a clamping area and overlapping areas at both ends of the clamping area, the thickness of which is half the thickness of the clamping area; and / or Each overlapping area is provided with a first connecting hole, through which the fasteners connect the two sets of clamping fixtures together.

3. The method according to claim 2, characterized in that, The length of the clamping area is determined by the following formula: In the formula, The length of the clamping area. The distance between the centers of the two first connecting holes in the clamping frame. The width of each clamping edge, The maximum shear deformation angle of the preform to be deformed. This is the first allowance.

4. The method according to claim 2, characterized in that, Each clamping frame has several second connecting holes distributed on its clamping area. These second connecting holes are used to accommodate the fasteners.

5. The method according to claim 1, characterized in that, The side length of the fixed base plate is determined by the following formula: In the formula, The side length of the fixed base plate. The distance between the centers of the two first connecting holes in each clamping frame. The shear deformation angle of the preform to be deformed. This is the second allowance.

6. The method according to claim 1, characterized in that, The limiting component also includes two second fixing bars; the two second fixing bars are located on the upper and lower sides of the fixed base plate respectively, and the second fixing bars on the same side are perpendicular to the first fixing bar. The two ends of each second fixing bar are connected to the deformation component by fasteners at two other opposite corners in the clamping frame.

7. The method according to claim 6, characterized in that, The length of the second fixing bar is greater than the length of the first fixing bar.

8. The method according to claim 6, characterized in that, Each first fixing strip has several third connecting holes at both ends, and each second fixing strip has several fourth connecting holes at both ends. The fasteners pass through the third connecting holes and the fourth connecting holes respectively, so that the deformable component is connected to the first fixing strip and the second fixing strip respectively.

9. The method according to claim 8, characterized in that, The distances between the centers of adjacent third connecting holes and adjacent fourth connecting holes are determined by the following formulas: In the formula, The distance between the centers of adjacent third connecting holes. The distance between the centers of adjacent fourth connecting holes. The distance between the centers of the two first connecting holes in the clamping frame. The shear deformation angle of the preform to be deformed.

10. The method according to claim 1, characterized in that, The preform to be deformed includes a deformation zone and a clamping zone, the deformation zone and the clamping zone together forming a cross shape; and / or The length of the clamping zone of the preform to be deformed is determined by the following formula: In the formula, The length of the clamping area of ​​the preform to be deformed is given. The distance between the centers of the two first connecting holes in the two overlapping areas on each clamping frame. The shear deformation angle of the preform to be deformed. This is the third margin.

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