Material with surface roughness as well as preparation device, method and application thereof

Abstract

The invention belongs to the field of dielectric and electrical insulation research, and particularly relates to a material with surface roughness and a preparation device, method and application of the material with the surface roughness, and the preparation device comprises a first outer plate mold, a second outer plate mold and a forming body mold unit. The forming body mold unit is arranged between the first outer plate mold and the second outer plate mold and detachably connected into an integrated structure through bolts, and the surfaces, facing the forming body mold unit, of the first outer plate mold and the second outer plate mold are rough surfaces with preset roughness; the forming body mold unit comprises a clamping piece mold, the clamping piece mold is provided with a casting cavity penetrating through the thickness direction of the clamping piece mold, and the clamping piece mold is further provided with a sprue gate communicated with the casting cavity. According to the method, dielectric materials with corresponding different surface roughness can be accurately and simply prepared, and the influence of the surface roughness on the electrical performance of a solid-solid interface and a gas-solid interface of electrical equipment can be conveniently researched.

Description

Technical Field

[0001] The invention belongs to the research field of dielectrics and electrical insulation, and in particular relates to a material with surface roughness and a preparation device, method and use thereof. Background Art

[0002] Most of the power equipment in actual engineering applications have solid-solid interfaces or gas-solid interfaces. Due to the manufacturing process of power equipment or the design requirements of insulation structure, the solid interface is often not completely smooth and has a certain degree of roughness. In the processing of the high-voltage and low-voltage end insert electrodes of AC GIS and GIL insulators, sandblasting is often used to make the surface have a certain degree of roughness to improve the bonding performance of the insert electrode and the insulating material and increase their bonding strength, which causes the insulating material to have a certain degree of roughness; the insulating surface of the high-voltage DC cable factory connector body is also sanded, so that the polished surface cannot be completely smooth and has a certain degree of roughness. However, in actual applications, the solid-solid interface and gas-solid interface of power equipment are areas of concentrated electricity, heat and force, and the discharge, ablation and breakdown damage caused by this often occur. In addition, in DC systems, power equipment operates in high temperature and high field environments for a long time, and charges are easily accumulated on the surface and inside of the power equipment, which leads to phenomena such as electric field distortion, surface flashover and material aging.

[0003] However, when studying the influence of solid-solid interface and gas-solid interface on electrical properties of insulation system of power equipment, the above-mentioned actual situation is not taken into consideration when preparing the samples used in the experiment. Instead, the samples used are insulating materials with smooth surfaces. This results in that the electrical properties test results of the insulating material samples are not consistent with their actual service conditions. Therefore, it is impossible to achieve better results in the structural optimization design and production process improvement of power equipment based on the measurement results.

[0004] Therefore, in order to study the influence of surface roughness on the electrical properties of solid-solid interface and gas-solid interface in the insulation system of power equipment, it is necessary to prepare dielectric materials with different surface roughness through a preparation device with surface roughness materials, so as to facilitate electrical tests such as dielectric constant, conductivity, breakdown and space charge, and study the influence of surface roughness on electrical properties, thereby providing theoretical support for the structural optimization design and production process improvement of power equipment. Summary of the invention

[0005] In order to solve the problems existing in the prior art, the purpose of the present invention is to provide a material with surface roughness and its preparation device, method and use, so as to facilitate the study of the influence of surface roughness on the electrical properties such as interface dielectric constant, conductivity, breakdown and space charge in power equipment.

[0006] To achieve the above object, the present invention provides the following technical solutions: A material with surface roughness comprises a sheet-shaped epoxy resin sample body, wherein the side surface of the epoxy resin sample body is a surface with preset roughness.

[0007] The present invention also provides use of the material with surface roughness as described above, wherein the material with surface roughness is used in a space charge measurement experiment to obtain the space charge of the material with surface roughness.

[0008] The present invention also provides a method for preparing the material with surface roughness as described above, wherein the material with surface roughness is formed by casting or 3D printing.

[0009] The present invention also provides a preparation device for the material having a surface roughness as described above, the preparation device is used for casting and molding the material having a surface roughness, comprising a first outer panel mold, a second outer panel mold and a forming body mold unit, the forming body mold unit is arranged between the first outer panel mold and the second outer panel mold, and the surfaces of the first outer panel mold and the second outer panel mold facing the forming body mold unit are set to rough surfaces with a preset roughness; The molding body mold unit comprises a clip mold, the clip mold is provided with a casting cavity penetrating the thickness direction of the clip mold, and the clip mold is also provided with a pouring port communicating with the casting cavity; The first outer panel mold, the second outer panel mold and the forming body mold unit are detachably connected to form an integrated structure through bolts, and the sides of the casting cavity and the pouring port are closed.

[0010] Preferably, the thickness of the side surface of the clip mold at the edges of the casting cavity and the pouring gate is greater than the thickness of the edge of the clip mold.

[0011] Preferably, the side surface of the clip mold is configured as a sealing surface of a preset width at the edge of the casting cavity and the pouring port, and a pure copper layer is provided on the sealing surface.

[0012] Preferably, the forming body mold unit further includes a partition mold, the partition mold and the clip mold are stacked on each other, and the side surface of the partition mold is set to a rough surface with a preset roughness.

[0013] Preferably, the forming body mold unit comprises a plurality of partition molds and a corresponding number of clip molds, and the plurality of partition molds and the corresponding number of clip molds are alternately stacked.

[0014] Preferably, a first liquid retention port is provided on the clip mold above the pouring port, the upper end of the pouring port is connected to the first liquid retention port, and a second liquid retention port having the same shape and size as the first liquid retention port is provided on the upper end of the partition mold.

[0015] Preferably, the outer peripheries of the first outer panel mold, the second outer panel mold and the forming body mold unit are provided with U-shaped grooves for bolts to pass through, and the openings of the U-shaped grooves extend to the outer edges of the first outer panel mold, the second outer panel mold and the forming body mold unit.

[0016] The method for preparing the material with surface roughness using the preparation device as described above of the present invention comprises the following steps: Applying a release agent on the surfaces of the first outer panel mold, the second outer panel mold and the forming body mold unit, and drying them; Placing the first outer panel mold and the second outer panel mold coated with a release agent on both sides of the forming body mold unit, and connecting the first outer panel mold, the second outer panel mold and the forming body mold unit into an integral structure by bolts; in the integral structure, the casting cavity and the side of the pouring port of the clip mold are closed; The prepared epoxy resin solution is poured into the casting cavity from the pouring port, the epoxy resin solution is degassed and solidified in a vacuum environment, and then the first outer panel mold, the second outer panel mold and the molding body mold unit are separated to obtain the material with surface roughness.

[0017] The present invention has the following beneficial effects: The side of the material with surface roughness provided by the present invention is a surface with a preset roughness. Therefore, when it is used to perform a space charge measurement experiment, it is possible to study the influence of surface roughness on electrical properties such as interface dielectric constant, conductivity, breakdown and space charge in power equipment. The obtained space charge distribution is also closer to the actual application scenario of epoxy resin insulating materials, which is beneficial to provide theoretical support for the structural optimization design and production process improvement of power equipment.

[0018] In the preparation device of the present invention, the surfaces of the first outer panel mold and the second outer panel mold facing the molding body mold unit are set to a rough surface with a preset roughness, that is, the mold surface that contacts the side of the epoxy resin sample body during casting is set to a rough surface, so that when the epoxy resin material is cured, the side of the epoxy resin sample body can have a certain side roughness after curing, and the roughness can be controlled by the mold surface roughness. Therefore, the preparation device of the present invention can be used to prepare materials with different surface roughness. At the same time, the present invention can also obtain samples of different thicknesses by using clip molds of different thicknesses. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of the explosion of the preparation device in the embodiment of the present invention; Figure 2 A schematic structural diagram of a first outer panel mold in an embodiment of the present invention; Figure 3A schematic structural diagram of a second outer panel mold in an embodiment of the present invention; Figure 4 A schematic structural diagram of a partition mold in an embodiment of the present invention; Figure 5 A schematic structural diagram of a clip mold in an embodiment of the present invention; FIG6 (a) is an electron microscope image of the epoxy sample prepared in the embodiment of the present invention (the mold surface is polished); FIG6 (b) is an electron microscope image of the epoxy sample prepared in the embodiment of the present invention (the mold surface is sandblasted with 120 mesh); FIG6 (c) is an electron microscope image of the epoxy sample prepared in the embodiment of the present invention (the mold surface is sandblasted with 80 mesh); FIG7(a) is a surface morphology of the epoxy sample shown in FIG6(a); FIG7(b) is a surface morphology of the epoxy sample shown in FIG6(b); and FIG7(c) is a surface morphology of the epoxy sample shown in FIG6(c).

[0020] In the figure, 1 is the first outer panel mold, 1-1 is the inner surface of the first outer panel mold, 2 is the second outer panel mold, 2-1 is the inner surface of the second outer panel mold, 3 is the partition mold, 3-1 is the left surface, 3-2 is the right surface, 4 is the clip mold, 4-1-casting cavity, 4-2-pouring port, 4-3-sealing surface, 5 is U-shaped groove, 6 is the second liquid retention port, and 7 is the first liquid retention port. DETAILED DESCRIPTION

[0021] Below, the present application is further described in conjunction with specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0022] It should be noted that the terms "first", "second", etc. in the description and claims of the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0023] The invention provides a material with surface roughness, which comprises a sheet-shaped epoxy resin sample body, and the side surface of the epoxy resin sample body is a surface with preset roughness.

[0024] The material with surface roughness of the present invention can be used in space charge measurement experiments to obtain the space charge of the material with surface roughness. When conducting space charge measurement experiments, a space charge measurement device with publication number CN113866525A considering the electrothermal coupling effect can be used.

[0025] Specifically, the material with surface roughness as described above in the present invention can be formed by casting or 3D printing.

[0026] The present invention takes casting as an example and provides a preparation device for the material having surface roughness as described above, referring to Figure 1 , Figure 2 and Figure 5 The preparation device provided in this embodiment includes a first outer panel mold 1, a second outer panel mold 2 and a forming body mold unit, the forming body mold unit is arranged between the first outer panel mold 1 and the second outer panel mold 2, and the surfaces of the first outer panel mold 1 and the second outer panel mold 2 facing the forming body mold unit are set to be rough surfaces with a preset roughness; the forming body mold unit includes a clip mold 4, such as Figure 5 As shown, the clip mold 4 is provided with a casting cavity 4-1 which runs through the thickness direction of the clip mold 4, and the clip mold 4 is also provided with a pouring port 4-2 which is connected to the casting cavity 4-1; the first outer panel mold 1, the second outer panel mold 2 and the forming body mold unit are detachably connected to form an integral structure by bolts, and the sides of the casting cavity 4-1 and the pouring port 4-2 are closed.

[0027] The method for preparing the material having surface roughness by using the preparation device of this embodiment includes the following steps: Apply a release agent on the surfaces of the first outer panel mold 1, the second outer panel mold 2 and the molded body mold unit, and dry them; The first outer panel mold 1 and the second outer panel mold 2 coated with a mold release agent are placed on both sides of the forming body mold unit, and the first outer panel mold 1, the second outer panel mold 2 and the forming body mold unit are connected into an integral structure by bolts; in the integral structure, the casting cavity 4-1 and the side of the pouring gate 4-2 of the clip mold 4 are closed, and the opening of the pouring gate 4-2 faces upward; The prepared epoxy resin solution is poured into the casting cavity 4-1 from the pouring port 4-2, and the epoxy resin solution is degassed and cured in a vacuum environment. Then, the first outer panel mold 1, the second outer panel mold 2 and the molding body mold unit are separated to obtain the material with surface roughness.

[0028] In the above embodiment, the surfaces of the first outer panel mold 1 and the second outer panel mold 2 have a certain degree of roughness. When the epoxy resin solution is cured, the surfaces of the epoxy resin in contact with the first outer panel mold 1 and the second outer panel mold 2 also form surfaces with a certain degree of roughness.

[0029] As a preferred embodiment of the present invention, refer to Figure 5 In this embodiment, the thickness of the side of the clip mold 4 at the edge of the casting cavity 4-1 and the pouring port 4-2 is greater than the thickness of the edge of the clip mold 4, that is, the inner edge side of the clip mold 4 ( Figure 5The thickness of the thicker black solid line part in the figure is greater than the outer edge side of the clip mold 4. The advantage of this design is that when the first outer panel mold 1, the second outer panel mold 2 and the forming body mold are connected into an integrated structure by bolts, the inner edge side of the clip mold 4 is thicker, so the inner edge side of the clip mold 4 fits more tightly with the first outer panel mold 1 and the second outer panel mold 2, and the sealing effect is better. This can avoid the leakage of epoxy resin solution due to the loose fit between the clip mold 4 due to the certain roughness of the first outer panel mold 1 and the second outer panel mold 2. If leakage occurs, the first outer panel mold 1, the second outer panel mold 2 and the clip mold 4 will be tightly adhered, which is not conducive to demoulding. In the present invention, the inner edge side of the clip mold 4 is designed relatively backward, so that a certain stress concentration is generated between the inner edge side of the clip mold 4 and the surface of the first outer panel mold 1 and the second outer panel mold 2, thereby making the clip mold 4 fit more closely with the first outer panel mold 1 and the second outer panel mold 2, and less likely to leak. In addition, even if leakage occurs, since the thickness of the inner edge side of the clip mold 4 is greater than the outer edge side of the clip mold 4, there will be a certain gap between the outer edge of the clip mold 4 and the first outer panel mold 1 and the second outer panel mold 2. When demolding, the outer edge of the clip mold 4 can be pressed to cause stress concentration of the epoxy resin (after curing) leaking from the inner edge of the clip mold 4, which is more conducive to demolding. Based on the optimization of the above structure, when preparing epoxy resin insulation samples using the preparation device of the present invention, a release agent may not be used or a smaller amount of release agent may be used, which is conducive to forming a rough surface on the surface of the epoxy resin insulation sample through the mold.

[0030] As a preferred embodiment of the present invention, based on the above-mentioned embodiment, in this embodiment, the side of the clip mold 4 is set as a sealing surface 4-3 of a preset width at the edge of the casting cavity 4-1 and the pouring port 4-2, and a pure copper layer is provided on the sealing surface 4-3. In this embodiment, by utilizing the deformability of pure copper, a better sealing effect can be formed on the contact parts of the clip mold 4 and the first outer plate mold 1 and the second outer plate mold 2 to prevent leakage, and it is also beneficial to discharge bubbles in the epoxy resin solution and the bubbles in the casting cavity 4-1 during the vacuuming process when preparing the epoxy resin insulation sample, effectively reducing the presence of bubble inclusions in the epoxy resin insulation sample.

[0031] As a preferred embodiment of the present invention, based on the above embodiments, in this embodiment, a partition mold 3 can also be set in the molding mold unit, and the partition mold 3 and the clip mold 4 are stacked on each other, and the side of the partition mold 3 is set to a rough surface with a preset roughness.

[0032] As a preferred embodiment of the present invention, based on the above embodiment, in this embodiment, the molding body mold unit can be provided with a plurality of partition molds 3 and a corresponding number of clip molds 4, and a plurality of partition molds 3 and a corresponding number of clip molds 4 are alternately stacked. In this way, a plurality of epoxy resin insulation samples can be prepared at one time, thereby improving the preparation efficiency.

[0033] As a preferred embodiment of the present invention, based on the above examples, see Figure 4 and Figure 5 In this embodiment, a first liquid retention port 7 is provided on the clip mold 4 above the pouring port 4-2, and the upper end of the pouring port 4-2 is connected to the first liquid retention port 7, and a second liquid retention port 6 having the same shape and size as the first liquid retention port 7 is provided on the upper end of the partition mold 3. With the above structural design, when the first outer panel mold 1, the second outer panel mold 2 and the forming body mold unit are detachably connected to form an integrated structure by bolts, a liquid retention pool will be formed on the upper part of the entire forming body mold unit, and the liquid retention pool can store a certain amount of epoxy resin solution, so that the epoxy resin solution can be replenished to the casting cavity 4-1 in time during pouring, thereby ensuring the integrity of the structure of each epoxy resin insulation sample.

[0034] As a preferred embodiment of the present invention, based on the above examples, see Figure 1-Figure 5 In this embodiment, the outer periphery of the first outer panel mold 1, the second outer panel mold 2 and the forming body mold unit is provided with a U-shaped groove 5 for the bolts to pass through, and the opening of the U-shaped groove 5 extends to the outer edge of the first outer panel mold 1, the second outer panel mold 2 and the forming body mold unit. The U-shaped groove 5 facilitates the removal of the bolts. After the bolts are loosened, they can be directly taken out laterally from the opening end of the U-shaped groove 5, which is conducive to the removal of the bolts and demoulding.

[0035] Example Reference Figure 1~Figure 5 The preparation device of the material with surface roughness in this embodiment includes a first outer panel mold 1, a second outer panel mold 2, a partition mold 3 and a clip mold 4. Several clip molds 4 and partition molds 3 are stacked in sequence, and the first outer panel mold 1 and the second outer panel mold 2 are respectively placed on both sides of all the clip molds 4. Figure 1Taking the orientation shown as an example, the left surface 3-1 and the right surface 3-2 of the partition mold 3, the inner surface 1-1 of the first outer plate mold (i.e., the right side of the first outer plate mold 1) and the inner surface 2-1 of the second outer plate mold (i.e., the left side of the second outer plate mold 2) are sandblasted with different meshes, and the sandblasting mesh is set according to the surface roughness requirements of the material. U-shaped grooves 5 are set at the same position on both sides of the first outer plate mold 1, the second outer plate mold 2, the partition mold 3 and the clip mold 4, and the above-mentioned mold components can be disassembled and fixedly connected by bolts and nuts of appropriate sizes. In this embodiment, a second liquid retention port 6 is set on the upper part of the partition mold 3, and a first liquid retention port 7 is set on the upper part of the clip mold 4, and a groove is opened below the first liquid retention port 7, which serves as a pouring port 4-2 and a casting cavity 4-1, and the second liquid retention port 6 and the first liquid retention port 7 have the same size.

[0036] The above-mentioned preparation device for the material with surface roughness in this embodiment comprises the following steps when preparing the material with surface roughness: S1, apply a release agent on the surfaces of the first outer panel mold 1, the second outer panel mold 2, the partition mold 3 and the clip mold 4, and place them in a 130°C oven for drying.

[0037] S2, assemble a preparation device with a material having a surface roughness, place each mold in sequence according to the order of the first outer panel mold 1, the clip mold 4 and the partition mold 3 are alternately arranged, and the second outer panel mold 2, and fix all the molds at the U-shaped groove 5 with bolts and nuts.

[0038] S3, pouring the prepared epoxy resin solution into step S2 through the second liquid retention port 6 and the first liquid retention port 7, the liquid level of the epoxy resin solution is lower than the height of the first outer panel mold 1 and the second outer panel mold 2.

[0039] S4, placing the mold processed in step S3 into a vacuum oven, and performing vacuum evacuation on the solution in the mold until no bubbles escape from the solution in the liquid retaining port.

[0040] S5, placing the mold processed in step S4 into a temperature-controlled oven, performing a segmented curing process on the solution in the mold, and preparing material samples with different surface roughnesses.

[0041] According to the required material thickness of the epoxy resin insulation sample, a clip mold 4 with a corresponding thickness is selected.

[0042] The epoxy resin samples with three different surface roughnesses were prepared using the above-mentioned device for preparing materials with surface roughness in this embodiment.

[0043] The cross-sections of three epoxy resin samples with different surface roughness were characterized and tested using a scanning electron microscope (SEM) of the VE9800S model of KEYENCE Company of Japan. At 200 times, the scanning electron microscope image of the cross-section of the epoxy resin sample prepared by the surface polishing mold is shown in Figure 6 (a), the scanning electron microscope image of the cross-section of the epoxy resin sample prepared by the surface 120 mesh sandblasting mold is shown in Figure 6 (b), and the scanning electron microscope image of the cross-section of the epoxy resin sample prepared by the surface 80 mesh sandblasting mold is shown in Figure 6 (c). From the cross-sectional images of the three epoxy samples with different surface roughness, it can be seen that the epoxy resin surface in Figure 6 (a) is smooth; the epoxy resin surface in Figure 6 (b) has a small amount of concave and convex changes; the epoxy resin surface in Figure 6 (c) is obviously concave and convex. It can be seen that there is indeed a difference in the surface roughness of the epoxy resin samples made by the polished, 120 mesh sandblasting and 80 mesh sandblasting molds, and the lower the sandblasting mesh number, the rougher the epoxy resin surface. The surface roughness of the epoxy resin samples was measured using a German Leica DCM8 laser confocal microscope. The surface morphology of the epoxy resin sample prepared by the surface polishing mold is shown in Figure 7 (a). Sa The surface morphology of the epoxy resin sample prepared by the 120-mesh sandblasting mold is shown in Figure 7 (b). Sa The surface morphology of the epoxy resin sample prepared by the 80-mesh sandblasting mold is shown in Figure 7 (c). Sa The surface roughness of the materials prepared by the preparation device with surface roughness material is obviously different, which shows the feasibility of the present invention.

[0044] It can be seen that the device and method of the present invention can be used to obtain dielectric materials with different surface roughness, which is beneficial to studying the influence of surface roughness on the electrical properties of the solid-solid interface and gas-solid interface of power equipment.

[0045] In summary, the present invention can accurately and simply prepare dielectric materials with corresponding different surface roughness by changing the surface roughness of the partition mold, which is convenient for studying the influence of surface roughness on the electrical properties of the solid-solid interface and the gas-solid interface of power equipment. A liquid retention port is arranged above the device of the present invention, which is convenient for vacuum extraction to ensure that there are no bubbles in the sample, and the pouring speed can be increased by pouring the solution, which greatly improves the sample preparation efficiency. The device of the present invention is provided with a U-shaped groove, which makes the device easy to assemble and disassemble, is conducive to non-destructive sampling and can be reused. Using the device of the present invention for sample preparation, dielectric materials with different surface roughness can be prepared, and the operation is simple, which provides experimental samples for related research on surface roughness.

[0046] Finally, it should be noted that the above preferred embodiments are only for illustrating the technical solutions of the present invention and are not limited thereto. For those skilled in the art, various changes such as modification, replacement or optimization can be made in terms of form and details without departing from the scope defined in the claims.

Claims

1. A material having a surface roughness, characterized in that: The invention comprises a sheet-shaped epoxy resin sample body, wherein the side surface of the epoxy resin sample body is a surface with a preset roughness.

2. Use of the material having surface roughness according to claim 1, characterized in that: The material with surface roughness is used in a space charge measurement experiment to obtain the space charge of the material with surface roughness.

3. A device for preparing the material with surface roughness according to claim 1, used for casting the material with surface roughness, characterized in that: The invention comprises a first outer panel mold (1), a second outer panel mold (2) and a forming body mold unit, wherein the forming body mold unit is arranged between the first outer panel mold (1) and the second outer panel mold (2), and the surfaces of the first outer panel mold (1) and the second outer panel mold (2) facing the forming body mold unit are set as rough surfaces with a preset roughness; The molding body mold unit comprises a clip mold (4), the clip mold (4) being provided with a casting cavity (4-1) penetrating the thickness direction of the clip mold (4), and the clip mold (4) being further provided with a pouring port (4-2) communicating with the casting cavity (4-1); The first outer panel mold (1), the second outer panel mold (2) and the molded body mold unit are detachably connected to form an integrated structure via bolts, and the sides of the casting cavity (4-1) and the pouring port (4-2) are sealed.

4. The preparation device according to claim 3, characterized in that: The thickness of the side surface of the clip mold (4) at the edges of the casting cavity (4-1) and the pouring port (4-2) is greater than the thickness of the edge of the clip mold (4).

5. The preparation device according to claim 3, characterized in that: The side surface of the clip mold (4) is configured as a sealing surface (4-3) of a preset width at the edges of the casting cavity (4-1) and the pouring port (4-2), and a pure copper layer is provided on the sealing surface (4-3).

6. The preparation device according to claim 3, characterized in that: The forming body mold unit further comprises a partition mold (3), wherein the partition mold (3) and the clip mold (4) are stacked on each other, and the side surface of the partition mold (3) is arranged as a rough surface with a preset roughness.

7. The preparation device according to claim 6, characterized in that: The forming body mold unit comprises a plurality of partition molds (3) and a corresponding number of clip molds (4), and the plurality of partition molds (3) and the corresponding number of clip molds (4) are alternately stacked.

8. The preparation device according to claim 7, characterized in that: A first liquid retention port (7) is provided on the clip mold (4) above the pouring port (4-2), the upper end of the pouring port (4-2) is connected to the first liquid retention port (7), and a second liquid retention port (6) having the same shape and size as the first liquid retention port (7) is provided on the upper end of the partition mold (3).

9. The preparation device according to claim 3, characterized in that: The outer peripheries of the first outer panel mold (1), the second outer panel mold (2) and the forming body mold unit are provided with U-shaped grooves (5) for the bolts to pass through, and the openings of the U-shaped grooves (5) extend to the outer edges of the first outer panel mold (1), the second outer panel mold (2) and the forming body mold unit.

10. A method for preparing the material having a surface roughness using the preparation device according to any one of claims 3 to 9, characterized in that: The process includes the following: Applying a release agent to the surfaces of the first outer panel mold (1), the second outer panel mold (2) and the molded body mold unit, and drying them; A first outer panel mold (1) and a second outer panel mold (2) coated with a mold release agent are placed on both sides of a molding mold unit, and the first outer panel mold (1), the second outer panel mold (2) and the molding mold unit are connected to form an integral structure by bolts; in the integral structure, the casting cavity (4-1) and the side of the pouring port (4-2) of the clip mold (4) are closed; The prepared epoxy resin solution is poured from the pouring port (4-2) into the casting cavity (4-1), the epoxy resin solution is degassed and solidified in a vacuum environment, and then the first outer panel mold (1), the second outer panel mold (2) and the molding body mold unit are separated to obtain the material having a surface roughness.

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