High-thermal-conductivity composite material forming mold and manufacturing method and application thereof

Abstract

The invention relates to a high-thermal-conductivity composite material forming mold and a manufacturing method and application thereof, and belongs to the technical field of composite material forming. The mold comprises a gel coat layer, a transition layer, a carbon fiber heat conduction layer and a glass fiber structure layer which are arranged from top to bottom. The transition layer comprises a glass fiber surfacing mat, and the coverage range of the transition layer is the same as that of the gel coat layer; the carbon fiber heat conduction layer comprises a carbon fiber fabric and mold resin, and the carbon fiber heat conduction layer is exposed out of the periphery of the coverage range of the gel coat layer by a set size; the glass fiber structure layer comprises a glass fiber chopped strand mat and mold resin, and the coverage range of the glass fiber structure layer is the same as that of the carbon fiber heat conduction layer. The carbon fiber heat conduction layer is used as a heat conduction structure of the mold, the local heating rate of the mold covered with the composite material raw material is increased, and the problem that the temperature of a forming mold is not uniform in the curing process of a composite material product is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of composite material molding, and in particular relates to a high thermal conductivity composite material molding die and a manufacturing method and application thereof. Background Art

[0002] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention, and should not necessarily be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

[0003] The vacuum bag molding method is a common molding method for glass fiber composite materials. Its principle is to lay the composite material raw materials on the molding mold, use the vacuum bag to prepare the vacuum system, and place the composite material raw materials, tire mold and vacuum bag as a whole in an environment with set temperature and pressure to complete the curing and molding. VARI molding technology also uses vacuum bags, which adds the process of resin infusion in the vacuum system.

[0004] The molding accuracy of composite materials depends on the accuracy of the mold. During the heating process, the mold temperature rises with the ambient temperature. The mold covered with composite materials is partially located at the innermost side of the entire vacuum system, and the ambient heat is transferred to the mold through the vacuum bag and the composite material raw materials. Due to the poor thermal conductivity of glass fiber, the mold covered with composite materials heats up slowly, while the mold part not covered with composite materials heats up quickly, resulting in large temperature differences at different locations during the product curing process, causing uneven stress release during the curing process, and the resulting product is easy to deform. The problem is particularly obvious with molds with complex shapes. Summary of the invention

[0005] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a high thermal conductivity composite material molding mold and its manufacturing method and application, and to add a carbon fiber thermal conductive layer in the tire mold to enhance the temperature uniformity at different positions of the tire mold during the product curing process.

[0006] In order to achieve the above object, the technical solution of the present invention is:

[0007] In a first aspect, a high thermal conductivity composite material forming mold includes a gel coat layer, a transition layer, a carbon fiber thermal conductive layer and a glass fiber structural layer arranged from top to bottom;

[0008] The transition layer includes a glass fiber surface mat and has the same coverage as the gel coat layer;

[0009] The carbon fiber heat conductive layer comprises carbon fiber fabric and mold resin, and the carbon fiber heat conductive layer is exposed to a set size outside the coverage of the gel coat layer;

[0010] The glass fiber structural layer comprises glass fiber chopped strand mat and mold resin, and the coverage of the glass fiber structural layer is the same as that of the carbon fiber heat conductive layer.

[0011] Optionally, the raw material for preparing the gel coat layer includes epoxy resin, and the gel coat layer includes a product molding surface.

[0012] Optionally, the transition layer has a set thickness.

[0013] Optionally, the carbon fibers in the carbon fiber heat conductive layer are continuous carbon fibers, and the volume ratio of the carbon fibers to the carbon fiber heat conductive layer is 60%-70%.

[0014] Optionally, the carbon fiber fabric includes carbon fibers oriented from edge to center.

[0015] Optionally, the glass fiber structural layer is made of glass fiber fabric, glass fiber chopped strand mat and mold resin.

[0016] Optionally, the high thermal conductivity composite material forming mold further includes a supporting frame, and the supporting frame is installed on a side of the glass fiber structural layer away from the carbon fiber thermal conductive layer.

[0017] In a second aspect, the method for manufacturing the above-mentioned high thermal conductivity composite material forming mold comprises the following steps:

[0018] S1. Spraying epoxy resin on the product molding surface of the mold to form a gel coat layer;

[0019] S2. Laying glass fiber surface felt on the gel coat layer to form a transition layer;

[0020] S3, laying carbon fiber fabric on the transition layer, with the laying range being larger than the gel coat layer, to form a carbon fiber heat conductive layer;

[0021] S4, laying glass fiber chopped strand mat on the carbon fiber heat conductive layer;

[0022] S5, using a vacuum bag to cover the tire mold, the transition layer, the carbon fiber heat conductive layer and the chopped fiber felt to form a vacuum system;

[0023] S6. Resin is introduced into the vacuum system and molded at a set temperature and pressure. After removing the mold, a high thermal conductivity composite material molding mold is obtained.

[0024] Optionally, in S1, the material of the mold includes: one or more of epoxy wood substitute, polyester wood substitute and HPL board.

[0025] Optionally, the method further includes step S7, installing a high thermal conductivity composite material forming mold on a supporting frame.

[0026] Thirdly, the application of the above-mentioned high thermal conductivity composite material molding mold in vacuum bag molding.

[0027] The beneficial effects of the present invention are:

[0028] 1. The present invention provides a high thermal conductivity composite material molding mold, which uses a carbon fiber thermal conductive layer as the heat conduction structure of the mold. When the mold is used to mold composite materials, the local heating rate of the mold covered by the composite material raw material is improved, thereby improving the uniformity of the mold temperature at the edge and center of the product, improving the problem of uneven molding mold temperature during the curing process of the composite material product, thereby reducing the stress caused by the local temperature difference of the product and improving the overall quality of the product.

[0029] 2. The present invention adopts the carbon fiber in the carbon fiber thermal conductive layer as the thermal conductive material, which has good plasticity and a wide range of applications. The carbon fiber thermal conductive layer is exposed at the edge of the mold and can directly absorb ambient heat through the vacuum system and conduct the heat to the center of the mold along the orientation of the carbon fiber, thereby reducing heat loss and achieving rapid heating of the mold. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0031] Figure 1 Schematic diagram of the structure of the high thermal conductivity composite material molding mold in Example 1.

[0032] Figure 2 It is a partially enlarged schematic diagram of the high thermal conductivity composite material forming mold in Example 1.

[0033] Figure 3 This is a flow chart of the method for manufacturing a high thermal conductivity composite material molding mold in Example 1.

[0034] Figure 4 Schematic diagram of the paving range of the high thermal conductivity composite material forming mold in Example 1.

[0035] Figure 5 This is an isometric view of the high thermal conductivity composite material molding die in Example 1.

[0036] Among them, 1. Gel coat layer; 2. Transition layer; 3. Carbon fiber thermal conductive layer; 4. Glass fiber structural layer; 5. Support frame. DETAILED DESCRIPTION

[0037] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0038] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0039] Example 1

[0040] A high thermal conductivity composite material forming mold, such as Figure 1 As shown, it includes a gel coat layer 1, a transition layer 2, a carbon fiber heat conductive layer 3 and a glass fiber structural layer 4 arranged from top to bottom;

[0041] The transition layer 2 comprises a glass fiber surface mat and has the same coverage as the gel coat layer 1;

[0042] like Figure 2 As shown, the carbon fiber heat conductive layer 3 includes carbon fiber fabric and mold resin, and the carbon fiber heat conductive layer 3 is exposed to a set size outside the coverage range of the gel coat layer 1;

[0043] The glass fiber structural layer 4 includes glass fiber chopped strand mat and mold resin, and the coverage of the glass fiber structural layer 4 is the same as that of the carbon fiber heat conductive layer 3 .

[0044] Through the above arrangement, the ambient heat can be transferred through the carbon fiber heat conductive layer 3, and the transfer path is located below the transition layer 2, so that the mold part covered by the composite material (specifically the gel coat layer 1) receives the heat conducted by the composite material raw material while receiving the heat transferred by the carbon fiber heat conductive layer 3 below, thereby improving the temperature uniformity of different positions of the mold.

[0045] The raw materials for preparing the gel coat layer 1 include epoxy resin, and the gel coat layer 1 includes a product molding surface. The product molding surface is in direct contact with the composite material raw material. The product molding surface determines the surface quality of the prepared product. The temperature uniformity of the present invention is specifically reflected in the temperature uniformity of each position of the gel coat layer 1 that is in direct contact with the composite material raw material.

[0046] The transition layer 2 serves to connect the gel coat layer 1 and the carbon fiber thermal conductive layer 3. It utilizes the uniform dispersion and good plasticity of the glass fiber surface felt to improve the density and connection strength between the gel coat layer 1 and the carbon fiber thermal conductive layer 3. It has a set thickness, and its thickness determines the thermal resistance from the carbon fiber thermal conductive layer 3 to the gel coat layer 1. Therefore, when the gel coat layer 1 is large in area, the distance between the center of the mold and the edge is far, and the thermal conductivity of the carbon fiber thermal conductive layer 3 cannot make the temperature uniform, a thinner transition layer 2 can be set in the center of the mold to reduce the thermal resistance of the transition layer 2 at the center of the mold, thereby further improving the temperature uniformity.

[0047] The carbon fibers in the carbon fiber heat conducting layer 3 are continuous carbon fibers, and the volume ratio of the carbon fibers to the carbon fiber heat conducting layer 3 is 70%, ensuring that the carbon fiber heat conducting layer 3 has a higher thermal conductivity.

[0048] The carbon fiber fabric includes carbon fibers oriented from edge to center, which is consistent with the desired heat conduction path.

[0049] The glass fiber structural layer 4 is made of glass fiber fabric, glass fiber chopped strand mat and mold resin, and is the main load-bearing component of the mold, providing strength and internal anti-deformation capability for the mold surface.

[0050] The high thermal conductivity composite material forming mold also includes a support frame 5, which is installed on the side of the glass fiber structural layer 4 away from the carbon fiber thermal conductive layer 3; 40*40*2.5mm carbon steel square tubes are used for welding, the square tubes are cross-crossed, and oblique ribs are added to ensure the rigidity of the entire frame, and all the docking positions are beveled to ensure secure welding.

[0051] The manufacturing method of the above-mentioned high thermal conductivity composite material molding mold is as follows: Figure 3 As shown, the following steps are included:

[0052] S1. Spray 0.6-0.8 mm thick epoxy resin on the product molding surface of the mold to form a gel coat layer 1. In order to reduce the edge defects of the product surface, the spraying range can include part of the mold edge area;

[0053] S2, laying glass fiber surface felt on the gel coat layer 1 to form a transition layer 2;

[0054] S3, such as Figure 4 As shown, a 0.5 mm thick carbon fiber fabric is laid on the transition layer 2, and the laying range is larger than the gel coat layer 1, including the entire mold area, to form a carbon fiber heat conductive layer 3;

[0055] S4, laying glass fiber chopped strand mat with a thickness of 10-15 mm on the carbon fiber heat conductive layer 3, which is the raw material of the glass fiber structural layer 4 and the main load-bearing component of the mold;

[0056] S5, using a vacuum bag to cover the tire mold, the gel coat layer 1, the transition layer 2, the carbon fiber heat conductive layer 3 and the chopped fiber felt as a whole to form a vacuum system;

[0057] S6. Introduce mold resin into the vacuum system and form it at a set temperature and pressure. During the process, the mold resin penetrates the glass fiber structural layer 4, the carbon fiber thermal conductive layer 3 and the transition layer 2 to form a structure in which each layer is tightly combined. After removing the mold, a high thermal conductivity composite material molding mold body is obtained.

[0058] S7, installing the high thermal conductivity composite material molding mold body on the support frame 5, bonding the support frame 5 and the glass fiber structure layer 4 of the high thermal conductivity composite material mold together, and spraying anti-rust paint on the support frame 5 after bonding to obtain Figure 5 The high thermal conductivity composite material molding mold shown.

[0059] In S1, the material of the tire mold is epoxy wood.

[0060] When the above-mentioned high thermal conductivity composite material molding mold is used in vacuum bag molding, the composite material raw material is laid in the range of the gel coat layer 1, but does not cover the range of the carbon fiber thermal conductive layer 3. Then, when heated and cured, the gel coat layer 1 at the edge of the product is subjected to the heat conducted by the outer composite material raw material and the heat conducted by the inner carbon fiber thermal conductive layer 3, as well as the environmental heat conducted laterally along the surface of the gel coat layer 1. The gel coat layer 1 in the center of the product is subjected to less environmental heat conducted laterally. Since the outer composite material raw material is mainly glass fiber with poor thermal conductivity, the heat conducted by the outer composite material raw material is also less. Since the thermal resistance of the carbon fiber thermal conductive layer 3 below is low, the heat can be conducted from the carbon fiber exposed at the edge of the mold to the gel coat layer 1 in the center of the product, thereby rapidly increasing the temperature of the gel coat layer 1 in the center of the product and improving the temperature uniformity of the molding mold during the curing process of the composite product.

[0061] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A high thermal conductivity composite material forming mold, characterized in that: It includes a gel coat layer, a transition layer, a carbon fiber heat conductive layer and a glass fiber structural layer arranged from top to bottom; The transition layer includes a glass fiber surface mat and has the same coverage as the gel coat layer; The carbon fiber heat conductive layer comprises carbon fiber fabric and mold resin, and the carbon fiber heat conductive layer is exposed to a set size outside the coverage of the gel coat layer; The glass fiber structural layer comprises glass fiber chopped strand mat and mold resin, and the coverage of the glass fiber structural layer is the same as that of the carbon fiber heat conductive layer.

2. The high thermal conductivity composite material forming mold according to claim 1, characterized in that: The raw materials for preparing the gel coat layer include epoxy resin, and the gel coat layer includes a product molding surface.

3. The high thermal conductivity composite material forming mold according to claim 1, characterized in that: The transition layer has a set thickness.

4. The high thermal conductivity composite material molding die according to claim 1, characterized in that: The carbon fibers in the carbon fiber heat-conducting layer are continuous carbon fibers, and the volume ratio of the carbon fibers to the carbon fiber heat-conducting layer is 60%-70%.

5. The high thermal conductivity composite material forming mold according to claim 1, characterized in that: The carbon fiber fabric includes carbon fibers oriented from edge to center.

6. The high thermal conductivity composite material forming mold according to claim 1, characterized in that: The glass fiber structural layer is made of glass fiber fabric, glass fiber chopped strand mat and mold resin.

7. The high thermal conductivity composite material forming mold according to claim 1, characterized in that: The high thermal conductivity composite material forming mold further comprises a supporting frame, and the supporting frame is installed on a side of the glass fiber structural layer away from the carbon fiber thermal conductive layer.

8. The method for manufacturing a high thermal conductivity composite material molding die according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1. Spraying epoxy resin on the product molding surface of the mold to form a gel coat layer; S2. Laying glass fiber surface felt on the gel coat layer to form a transition layer; S3, laying carbon fiber fabric on the transition layer, with the laying range being larger than the gel coat layer, to form a carbon fiber heat conductive layer; S4, laying glass fiber chopped strand mat on the carbon fiber heat conductive layer; S5, using a vacuum bag to cover the tire mold, the transition layer, the carbon fiber heat conductive layer and the chopped fiber felt to form a vacuum system; S6. Resin is introduced into the vacuum system and molded at a set temperature and pressure. After removing the mold, a high thermal conductivity composite material molding mold is obtained.

9. The manufacturing method according to claim 8, characterized in that: In S1, the material of the mold includes: one or more of epoxy wood substitute, polyester wood substitute and HPL board; Optionally, the method further includes step S7, installing a high thermal conductivity composite material forming mold on a supporting frame.

10. Use of the high thermal conductivity composite material molding mold according to any one of claims 1 to 7 in vacuum bag molding.

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