Preparation method for improving temperature resistance of composite material external adjusting sheet

Abstract

The invention belongs to the technical field of composite materials, and relates to a preparation method for improving the temperature resistance of an external adjusting sheet of a composite material. A carbon fiber and glass fiber composite laying layer is adopted in the outer adjusting sheet laying layer, carbon fiber prepreg is used in the front section, glass fiber prepreg is used in the rear section, meanwhile, the length proportions of the glass fiber prepreg in different laying layers are different, and the proportions of the glass fiber laying layers, from the front end to the tail end, of the composite material outer adjusting sheet in all the laying layers are gradually increased. The method has the biggest advantage that the temperature resistance of the outer adjusting sheet in the length direction can be improved to different degrees, and the requirement of the external temperature gradually increased from the head to the tail of the outer adjusting sheet on the temperature resistance of the material is met. Compared with a metal-based external adjusting sheet, the composite material external adjusting sheet prepared by the invention can effectively reduce weight, has gradient temperature bearing capacity, has great technical advantages, and has important significance in application of novel resin-based composite materials for aerospace.

Description

Technical Field

[0001] The invention belongs to the technical field of composite materials and relates to a preparation method for improving the temperature resistance of a composite material outer regulating sheet. Background Art

[0002] Resin-based composite materials have attracted wide attention due to their designability, high specific strength, and light weight. They have very important applications in wind turbine blades, large aircraft, and new generation aerospace vehicles. At present, resin-based composite materials are increasingly used in aero engines and are also beginning to be used in external adjustment plates.

[0003] During the test run of the composite outer adjustment plate of an aircraft engine, the temperature of the inner surface of the outer adjustment plate rises due to the influence of the heat flow from the tail nozzle, resulting in local bulging. The short-term high temperature environment will cause the composite resin to soften quickly and lose the interlayer interface bonding force, resulting in interlayer delamination, and then the phenomenon of bulging on the inner surface, causing the strength and other mechanical properties of the composite material to decrease, affecting the reliability of the composite outer adjustment plate.

[0004] High-strength glass fiber has low thermal conductivity, excellent thermal insulation performance, and high-temperature stability. It can be used as an insulation layer in composite materials in high-temperature environments and is an ideal material for improving the temperature resistance of composite materials. Summary of the invention

[0005] To solve the above problems, the purpose of the present invention is to provide a preparation method for improving the temperature resistance of a composite material outer adjustment plate. The preparation method is simple, and the temperature resistance of the outer adjustment plate in the length direction can be gradually improved along the length direction, meeting the requirements of the material's temperature resistance as the external temperature gradually increases from the head to the tail of the outer adjustment plate.

[0006] To achieve the above-mentioned purpose, the present invention provides a preparation method for improving the temperature resistance of a composite material outer adjustment sheet, comprising the following steps: first, using a polyimide resin solution and carbon fiber to prepare a carbon fiber prepreg by a wet method, and using a polyimide resin solution and glass fiber to prepare a glass fiber prepreg in the same way; the front section of the outer adjustment sheet uses the carbon fiber prepreg, and the rear section uses the glass fiber prepreg, the carbon fiber prepreg has a thickness of 0.10 to 0.15 mm, and the glass fiber prepreg has a thickness of 0.20 to 0.30 mm. During the paving process, for every 2 to 3 layers of carbon fiber prepreg laid in the front section, a corresponding layer of glass fiber prepreg is laid in the rear section. After the paving is completed, a hot pressing process is used to perform curing and molding according to the set polyimide resin composite material curing process.

[0007] The resin content of the polyimide resin solution is 40% to 55%.

[0008] The carbon fiber is one of T300, T800, CCF300 and CCF800.

[0009] The glass fiber is one of SW220C, SW200D, SW240F, SW280F, and QW280A.

[0010] The resin content of the carbon fiber prepreg and the glass fiber prepreg is 30-45%.

[0011] The length of the glass fiber prepreg accounts for 18% to 25% of the total length of the outer adjustment sheet, and the gradient length of two adjacent layers of glass fiber prepreg accounts for 0.5% to 1% of the total length of the outer adjustment sheet.

[0012] The hot pressing process uses a hot pressing tank molding process, and the curing molding temperature is 350°C to 400°C.

[0013] The wet prepreg machine for wet-processing carbon fiber prepreg and glass fiber prepreg has a winding speed of 1.7 to 2.5 m / min and a drying temperature of 80 to 95°C.

[0014] Advantages of the present invention:

[0015] The advantage of the present invention is that the composite material outer adjustment sheet is formed in an integrated manner during the preparation process, without adding any steps and is simple to operate. The temperature resistance of the outer adjustment sheet in the length direction can be improved to varying degrees by simply designing the length ratio of the carbon fiber and glass fiber prepregs in different layers, thereby meeting the gradually increasing temperature resistance requirements of the outer adjustment sheet from the head to the tail, and the temperature resistance can be improved by 10 to 20°C.

[0016] Compared with metal-based outer adjustment sheets, the resin-based composite material outer adjustment sheet prepared by the present invention can reduce weight to the greatest extent and has gradient temperature bearing capacity, thus having great technical advantages and being of great significance for the application of new resin-based composite materials for aerospace. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of carbon fiber / glass fiber prepreg composite layup. DETAILED DESCRIPTION

[0018] The present invention is described in detail below in conjunction with the accompanying drawings:

[0019] In order to have a clearer understanding of the technical features, purposes and beneficial effects of the present invention, the technical solution of the present invention is now described in detail below, but it should not be understood as a definition of the applicable scope of the present invention.

[0020] The prepreg is prepared by wet method, and the carbon fiber prepreg and glass fiber prepreg are cut into sheets according to the size of each layer, and laid on the mold according to the proportion of each layer. After laying, it is placed in an autoclave for high-temperature curing to obtain a resin-based composite material outer adjustment sheet with gradient high-temperature resistance, which is specifically:

[0021] A preparation method for improving the heat resistance of a composite material outer adjustment plate comprises the following steps: first, a carbon fiber prepreg is prepared by a wet method using a polyimide resin solution and carbon fiber, wherein the resin content of the polyimide resin solution is 40% to 55%; the carbon fiber is one of T300, T800, CCF300, and CCF800. A glass fiber prepreg is prepared by the same method using a polyimide resin solution and glass fiber; the glass fiber is one of SW220C, SW200D, SW240F, SW280F, and QW280A.

[0022] The resin content of the carbon fiber prepreg and the glass fiber prepreg is 30-45%.

[0023] The wet prepreg machine for wet-processing carbon fiber prepreg and glass fiber prepreg has a winding speed of 1.7 to 2.5 m / min and a drying temperature of 80 to 95°C.

[0024] like Figure 1 As shown, the front section of the outer adjustment sheet uses carbon fiber prepreg, and the rear section uses glass fiber prepreg. The thickness of the carbon fiber prepreg is 0.10-0.15 mm, and the thickness of the glass fiber prepreg is 0.20-0.30 mm. During the paving process, for every 2-3 layers of carbon fiber prepreg laid in the front section, a corresponding layer of glass fiber prepreg is laid in the rear section. The length of the glass fiber prepreg accounts for 18%-25% of the total length of the outer adjustment sheet, and the gradient length of two adjacent layers of glass fiber prepreg accounts for 0.5%-1% of the total length of the outer adjustment sheet.

[0025] After the paving is completed, a hot pressing process is used to perform curing and molding according to a set curing process of the polyimide resin composite material. The hot pressing process uses a hot press molding process, and the curing and molding temperature is 350°C to 400°C.

[0026] Embodiment 1:

[0027] 1. Preparation of carbon fiber prepreg and glass fiber prepreg

[0028] CCF800 carbon fiber and SW280F glass fiber are used as reinforcements respectively, the resin content of the polyimide resin solution is 40%, and the prepregs are prepared by a wet method. The resin content of the carbon fiber prepreg is 32±5%, and the resin content of the glass fiber prepreg is 35±5%.

[0029] 2. Preparation of resin-based composite outer adjustment sheet with gradient temperature resistance

[0030] The prepared prepregs are manually laid in accordance with the process requirements. Carbon fiber prepreg is used in the front section and glass fiber prepreg is used in the back section. Due to the different thicknesses of the two prepregs, during the laying process, for every two layers of carbon fiber prepreg laid in the front section, one layer of glass fiber prepreg is laid in the back section. The table shows the percentage of carbon fiber prepreg and glass fiber prepreg in each layer in the length of the adjustment sheet. After each layer is laid, it is cured and formed using the set process program using the autoclave method, and the curing temperature is 360°C. After curing, it is cooled to below 60°C and taken out of the tank, completing the preparation of the resin-based composite material outer adjustment sheet with gradient high temperature resistance.

[0031]

[0032] Embodiment 2:

[0033] 1. Preparation of carbon fiber prepreg and glass fiber prepreg

[0034] CCF300 carbon fiber and QW280A glass fiber are used as reinforcements respectively, the resin content of the polyimide resin solution is 45%, and 1000mm wide prepregs are prepared by wet method. The resin content of the carbon fiber prepreg is 36±5%, and the resin content of the glass fiber prepreg is 40±5%.

[0035] 2. Preparation of resin-based composite outer adjustment sheet with gradient temperature resistance

[0036] The prepared prepregs are manually laid in accordance with the process requirements. Carbon fiber prepreg is used in the front section and glass fiber prepreg is used in the back section. Due to the different thicknesses of the two prepregs, during the laying process, for every two layers of carbon fiber prepreg laid in the front section, one layer of glass fiber prepreg is laid in the back section. The table shows the percentage of carbon fiber prepreg and glass fiber prepreg in each layer in the length of the adjustment sheet. After each layer is laid, it is cured and formed using the set process program using the autoclave method, and the curing temperature is 380°C. After curing, it is cooled to below 60°C and taken out of the tank, completing the preparation of the resin-based composite material outer adjustment sheet with gradient high temperature resistance.

[0037]

[0038] Embodiment 3:

[0039] 1. Preparation of carbon fiber prepreg and glass fiber prepreg

[0040] T300 carbon fiber and SW240F glass fiber are used as reinforcements respectively, the resin content of the polyimide resin solution is 50%, and 1000mm wide prepregs are prepared by wet method. The resin content of the carbon fiber prepreg is 40±5%, and the resin content of the glass fiber prepreg is 45±5%.

[0041] 2. Preparation of resin-based composite outer adjustment sheet with gradient temperature resistance

[0042] The prepared prepregs are manually laid in accordance with the process requirements. Carbon fiber prepreg is used in the front section and glass fiber prepreg is used in the back section. Due to the different thicknesses of the two prepregs, during the laying process, for every two layers of carbon fiber prepreg laid in the front section, one layer of glass fiber prepreg is laid in the back section. The table shows the percentage of carbon fiber prepreg and glass fiber prepreg in each layer in the length of the adjustment sheet. After each layer is laid, it is cured and formed using the set process program using the autoclave method, and the curing temperature is 390°C. After curing, it is cooled to below 60°C and taken out of the tank, completing the preparation of the resin-based composite material outer adjustment sheet with gradient high temperature resistance.

[0043]

Claims

1. A method for preparing a composite material outer adjustment sheet for improving its temperature resistance, comprising the following steps: First, a carbon fiber prepreg is prepared by a wet method using a polyimide resin solution and carbon fiber, and a glass fiber prepreg is prepared by using a polyimide resin solution and glass fiber in the same way; the carbon fiber prepreg is used in the front section of the outer adjustment plate, and the glass fiber prepreg is used in the rear section. The thickness of the carbon fiber prepreg is 0.10-0.15 mm, and the thickness of the glass fiber prepreg is 0.20-0.30 mm. During the paving process, for every 2-3 layers of carbon fiber prepreg laid in the front section, a layer of glass fiber prepreg is laid in the rear section. After the paving is completed, a hot pressing process is adopted to perform curing and molding according to the set polyimide resin composite material curing process.

2. A method for preparing a composite material outer adjustment sheet for improving heat resistance according to claim 1, characterized in that: The resin content of the polyimide resin solution is 40% to 55%.

3. The method for preparing a composite material outer adjustment sheet for improving heat resistance according to claim 1, characterized in that: The carbon fiber is one of T300, T800, CCF300 and CCF800.

4. The method for preparing a composite material outer adjustment sheet for improving heat resistance according to claim 1, characterized in that: The glass fiber is one of SW220C, SW200D, SW240F, SW280F, and QW280A.

5. The method for preparing a composite material outer adjustment sheet for improving heat resistance according to claim 1, characterized in that: The resin content of the carbon fiber prepreg and the glass fiber prepreg is 30-45%.

6. The method for preparing a composite material outer adjustment sheet for improving heat resistance according to claim 1, characterized in that: The length of the glass fiber prepreg accounts for 18% to 25% of the total length of the outer adjustment sheet, and the gradient length of two adjacent layers of glass fiber prepreg accounts for 0.5% to 1% of the total length of the outer adjustment sheet.

7. The method for preparing a composite material outer adjustment sheet for improving heat resistance according to claim 1, characterized in that: The hot pressing process uses a hot pressing tank molding process, and the curing molding temperature is 350°C to 400°C.

8. The method for preparing a composite material outer adjustment sheet for improving heat resistance according to claim 1, characterized in that: The wet prepreg machine for wet-processing carbon fiber prepreg and glass fiber prepreg has a winding speed of 1.7 to 2.5 m / min and a drying temperature of 80 to 95°C.

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