Method for evaluating physical properties of laminated board through physical properties of fabric

Abstract

The invention relates to a method for evaluating the physical performance of a laminated board through the physical performance of fabric. The method comprises the steps that the density rho G of fibers in the fabric, the fabric mass ms, the fabric area A and the fabric thickness h are obtained; based on the fabric mass ms and the fabric area A, determining the mass per unit area of the fabric as rho A; and determining the physical properties of the laminated board based on the mass per unit area [rho] A, the density [rho] G of the fibers in the fabric and the thickness h of the fabric, the physical properties of the laminated board including at least one of the fiber volume content FVFG of the laminated board and the single layer thickness CPT of the fabric in the laminated board, and the laminated board is composed of multiple layers of fabrics. According to the method and the device, the mass per unit area of the fabric can be quickly determined by acquiring the related easy-to-test data of the fabric, so that the physical performance of the laminated board is evaluated, the evaluation time and resources are greatly saved, the efficiency is improved, errors caused by subjective judgment and experience estimation are avoided, and the evaluation result of the physical performance of the laminated board is more accurate.

Description

Technical Field

[0001] This application relates to the field of laminate performance evaluation, and particularly to a method for evaluating the physical properties of laminates from the physical properties of fabrics. Background Art

[0002] Laminates prepared from fiber fabrics are widely used in the fields of aviation, aerospace, and wind power generation. Among them, the physical properties of laminates, such as the fiber content of laminates and the single-layer thickness of fabrics in laminates, are important factors affecting the performance of laminates.

[0003] Currently, the fiber content of laminates is usually determined by wettability experiments, which are inefficient and have poor result accuracy. Summary of the Invention

[0004] To overcome the problems in the related art, this application provides a method for evaluating the physical properties of laminates from the physical properties of fabrics.

[0005] According to an embodiment of the present disclosure, there is provided a method for evaluating the physical properties of laminates from the physical properties of fabrics, including the following steps:

[0006] Obtain the density ρ of the fibers in the fabric G , the mass m of the fabric s , the area A of the fabric, and the thickness h of the fabric;

[0007] Based on the mass m of the fabric s and the area A of the fabric, determine that the mass per unit area of the fabric is ρ A ;

[0008] Based on the mass per unit area of ρ A , the density ρ of the fibers in the fabric G and the thickness h of the fabric, determine the physical properties of the laminate, where the physical properties of the laminate include at least one of the fiber volume fraction FVF G of the laminate and the single-layer thickness CPT of the fabric in the laminate, and the laminate is composed of multiple layers of the fabric.

[0009] In some embodiments, the determining the mass per unit area ρ of the fabric based on the mass m of the fabric s and the area A of the fabric includes: A :

[0010] Based on the mass m of the fabric s and the area A of the fabric, obtain that the mass per unit area of the fabric is where the unit of the mass m of the fabric s is g, the unit of the area A of the fabric is cm 2 , and the mass per unit area ρA The unit is g / m 2 .

[0011] In some embodiments, based on the mass per unit area being ρ A , the density of the fibers in the fabric ρ G and the fabric thickness h, the physical properties of the laminate are determined, including:

[0012] The fiber volume content in the laminate where ρ G is the density of the fibers in the fabric, with the unit g / cm 3 , h is the fabric thickness, with the unit mm, ρ A is the mass per unit area, and both k and b are coefficients, where the coefficient k and the coefficient b are related to the fabric porosity φ and the fabric compression ratio β.

[0013] In some embodiments, based on the mass per unit area ρ A , the density of the fibers in the fabric ρ G and the fabric thickness h, the physical properties of the laminate are determined, including:

[0014] The single-layer thickness of the fabric in the laminate ρ A is the mass per unit area, FVF G is the fiber volume content, ρ G is the density of the fibers in the fabric, and the unit of the single-layer thickness CPT of the fabric in the laminate is mm.

[0015] In some embodiments, the method for determining the coefficient k and the coefficient b includes:

[0016] Based on the mass per unit area ρ A , the density of the fibers in the fabric ρ G and the fabric thickness h, the fabric porosity φ of the fabric is obtained;

[0017] The laminate thickness h G and the number of fabric layers n of the laminate are obtained. Based on the laminate thickness h G , the number of fabric layers n and the fabric thickness h, the fabric compression ratio β of the fabric is determined;

[0018] Based on the fabric porosity φ, the fabric compression ratio β and the fiber volume content FVF G , the coefficient k and the coefficient b are determined.

[0019] In some embodiments, based on the fabric porosity φ, the fabric compression ratio β and the fiber volume content FVF G, determining the coefficient k and the coefficient b includes:

[0020] Using the least squares method to perform linear fitting on the fabric porosity φ and the fabric compression ratio β to determine a first function, where the first function is a function of the fabric compression ratio β with respect to the fabric porosity φ;

[0021] Using the least squares method for the fiber volume fraction FVF G and the ratio of the fabric compression ratio β to the fabric porosity φ to perform linear fitting to determine a second function, where the second function is a function of the fiber volume fraction FVF G with respect to the ratio of the fabric compression ratio β to the fabric porosity φ;

[0022] Fusing the first function and the second function to obtain a third function;

[0023] Based on the third function and the fabric porosity φ, determine the coefficient k and the coefficient b.

[0024] In some embodiments, the determining the fabric compression ratio β based on the laminate thickness h G , the number of fabric layers n, and the fabric thickness h includes:

[0025] Taking the ratio of the laminate thickness h G to the number of fabric layers n as the measured value h of the single-layer thickness of the fabric in the laminate 1 ;

[0026] Taking the ratio of the measured value h of the single-layer thickness of the fabric in the laminate 1 to the fabric thickness h as the fabric compression ratio β.

[0027] In some embodiments, the method for determining the unit area mass ρ A includes:

[0028] Calculating the fabric mass per unit area of multiple fabrics respectively, and taking the average value of the fabric masses per unit area of multiple fabrics as the unit area mass ρ A .

[0029] In some embodiments, the method for preparing the laminate includes:

[0030] Adjusting the humidity of the fabric and the resin respectively;

[0031] Cutting the fabric into a fixed shape with a fixed size, and arranging the fabric in the same direction to be laid layer by layer in a mold to form a laid fabric;

[0032] Pouring the resin into the laid fabric to form a poured fabric;

[0033] Demold the fabric after the infusion is completed and cured by heating to form the laminate.

[0034] In some embodiments, the method further includes:

[0035] Before performing the infusion, cover a sealing film outside the mold, evacuate the sealing film to make the vacuum degree inside the sealing film be a preset vacuum degree, where the range of the preset vacuum degree is 885 mbar - 995 mbar.

[0036] The technical solutions provided by the embodiments of the present application may include the following beneficial effects: By obtaining relevant easily measurable data of the fabric, the present application can quickly determine the mass per unit area of the fabric, and then evaluate the physical properties of the laminate, greatly saving the evaluation time and resources. During the evaluation process of the physical properties of the laminate, since there is no need for the cumbersome process of a large number of tests on the laminate, the dependence on the finished laminate of the traditional evaluation method is avoided, the time cost of the laminate manufacturing and testing links is reduced, and the efficiency is improved. Moreover, the present application establishes a reliable association between the physical properties of the fabric and the physical properties of the laminate, avoiding the errors caused by subjective judgment and empirical estimation, and making the evaluation result of the physical properties of the laminate more accurate.

[0037] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The drawings herein are incorporated into the specification and form a part of the specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application.

[0039] Figure 1 is a method for evaluating the physical properties of a laminate from the physical properties of a fabric shown according to an exemplary embodiment.

[0040] Figure 2 is a method for determining coefficient k and coefficient b shown according to an exemplary embodiment.

[0041] Figure 3 is a method for preparing a laminate shown according to an exemplary embodiment. DETAILED DESCRIPTION

[0042] Exemplary embodiments will be described in detail herein, and examples thereof are shown in the accompanying drawings. When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0043] Laminates prepared from fiber fabrics are widely used in fields such as aviation, aerospace, and wind power. Among them, the physical properties of the laminate, such as the fiber content of the laminate and the single-layer thickness of the fabric in the laminate, are important factors affecting the performance of the laminate. Currently, wetting experiments are usually used to determine the fiber content of the laminate, and this experiment is inefficient and has poor result accuracy.

[0044] The present application provides a method for evaluating the physical properties of a laminate from the physical properties of a fabric. By obtaining various easily measurable parameters of the fibers in the fabric, the physical properties of the laminate made of the fabric can be determined, so that without going through the cumbersome laminate production process, relatively accurate physical properties of the laminate can be obtained. This not only saves the evaluation time cost and economic cost, but also can obtain reliable evaluation data, improves the evaluation efficiency, and is conducive to large-scale promotion and use.

[0045] A method for evaluating the physical properties of a laminate from the physical properties of a fabric provided by the present application, as Figure 1 shown, includes the following steps:

[0046] S1. Obtain the density ρ of the fibers in the fabric G , the mass m of the fabric s , the area A of the fabric, and the thickness h of the fabric.

[0047] In this step, the fabric can be, for example, one of a glass fiber fabric or a carbon fiber fabric. The unit of the density ρ of the fibers in the fabric G is g / cm 3 , and it can be obtained by directly measuring the fabric or by image processing. Among them, it can be directly measured by a fabric density mirror, or the density ρ of the fibers in the fabric can be obtained by using the image processing method to analyze the high-definition photo of the fabric through image processing software G . The unit of the mass m of the fabric s is g, and it can be obtained by measuring with an electronic balance. The unit of the area A of the fabric is cm 2, in one embodiment, a preset fabric area A can be set. The specified numerical value of the preset fabric area A can be directly obtained using a fabric acquisition tool. In other embodiments, the fabric area A of the fabric can also be measured and obtained by using professional image processing software through an image processing method. The unit of the fabric thickness h is mm and can be obtained by using instruments such as a micrometer. In order to obtain a more accurate density ρ of the fibers in the fabric G , the fabric mass m s , the fabric area A, and the fabric thickness h, the density ρ of the fibers in the fabric G , the fabric mass m s , the fabric area A, and the fabric thickness h of the same fabric can be measured multiple times and the average value can be taken.

[0048] S2. Based on the fabric mass m s and the fabric area A, determine that the mass per unit area of the fabric is ρ A .

[0049] The unit of the mass per unit area of the fabric is g / m 2 , which is used to characterize the mass performance of the fabric. In this application, the mass per unit area of the fabric can be obtained through the following calculation method:

[0050]

[0051] where ρ A is the mass per unit area of the fabric, and the unit of the mass per unit area ρ of the fabric A is g / m 2 , the unit of the fabric mass m s is g, and the unit of the fabric area A is cm 2 . The larger the mass per unit area of the fabric, the better the quality of the fabric. In order to obtain an accurate mass per unit area of the fabric, the mass of the fabric per unit area of multiple fabrics of the same specification can be calculated respectively, and the average value of the masses of the fabrics per unit area of multiple fabrics can be used as the mass per unit area ρ A . Among them, fabrics of the same specification refer to fabrics with the same fiber type, fiber density, knitting method, fabric thickness, and unit area.

[0052] S3. Based on the mass per unit area being ρ A , the density ρ of the fibers in the fabric G and the fabric thickness h, determine the physical properties of the laminate. Among them, the physical properties of the laminate include at least one of the fiber volume fraction FVF G of the laminate and the single-layer thickness CPT of the fabric in the laminate. Among them, the laminate is composed of multiple layers of the same fabric.

[0053] In step S3, the specifications of each layer of the multi-layer fabric used to form the laminate are the same, and the multi-layer fabric is connected together by resin. Since the laminate is composed of multi-layer fabric, the performance of the laminate can be reflected through the performance of the fabric, and it can be used to evaluate the performance of the laminate. The evaluation method of this application is only applicable to the case where the multi-layer fabrics are all of the same specification, and is not applicable to the case where the multi-layer fabrics are of different specifications.

[0054] Among them, the physical properties of the laminate include the fiber volume fraction FVF G (Fiber Volume Fraction of Glass Fiber in Laminate), which is used to characterize the proportion of fibers in the total volume of the laminate and is a key index for measuring the performance of the laminate. The fiber volume fraction in the laminate can be obtained in the following way:

[0055]

[0056] Among them, ρ G has the unit of g / cm 3 , which is used to characterize the density of fibers in the fabric, h has the unit of mm and is used to characterize the fabric thickness, ρ A has the unit of g / m 2 , which is used to characterize the mass per unit area, and both k and b are coefficients. Among them, for the laminate prepared from fabrics of the same specification, the coefficient k and the coefficient b are related to the fabric porosity φ and the fabric compression ratio β of this specification fabric. ρ G and h are the values obtained in S1, and ρ A is the value calculated in S2.

[0057] The fabric porosity φ is used to characterize the percentage of the pore volume in the fabric in the total volume of the fabric. The fabric porosity φ can be calculated and obtained in the following way:

[0058]

[0059] Among them, ρ A is the mass per unit area, and ρ A is the value calculated in S2, ρ G is the density of fibers in the fabric, and ρ G is the value obtained in S1, and h is the fabric thickness and h is the value obtained in S1. Since the total volume of the fabric is equal to the sum of the fiber volume and the pore volume, then the ratio of the fiber volume to the total volume of the fabric and the ratio of the pore volume to the total volume of the fabric add up to 100%. Since is the percentage of the fiber volume in the fabric in the total volume of the fabric, the fabric porosity of fabrics of the same specification is the same.

[0060] For laminates made of fabrics of the same specification, the fabric compression ratio β is the same. To obtain the fabric compression ratio β, it is necessary to actually use fabrics of this specification to prepare laminates in order to obtain relevant data of the prepared laminates. The relevant data of the prepared laminates are combined with the relevant data of the fabrics to calculate the fabric compression ratio β. Among them, the relevant data of the prepared laminates include the laminate thickness h G and the number of fabric layers n of the laminate. Among them, the laminate thickness h G can be obtained by measurement. In order to obtain a more accurate value, the thicknesses at different positions of the laminate can be measured and the average value can be taken as the laminate thickness h G , and the number of fabric layers n of the laminate is obtained by counting during the preparation of the laminate.

[0061] The laminate thickness h G The ratio to the number of fabric layers n is the measured value h of the single-layer thickness of the fabric in the laminate 1 , that is The measured value h of the single-layer thickness of the fabric in the laminate 1 The ratio to the fabric thickness h is the fabric compression ratio β, that is Obtain where h 1 is the measured value of the single-layer thickness of the fabric in the laminate. The unit of the measured value h of the single-layer thickness of the fabric in the laminate is mm, n is the number of fabric layers for preparing the laminate, h is the fabric thickness, and the unit of the fabric thickness h is mm. Among them, the measured value h of the single-layer thickness of the fabric in the laminate 1 can be obtained by measurement; the number of fabric layers n can be obtained by counting. During the preparation of the laminate, when the fabrics are laid layer by layer, the number of laid fabrics can be directly recorded; the fabric thickness h is the value obtained in S1. 1 The larger the fabric porosity φ, the easier the fabric is to be compressed, that is, the smaller the fabric compression ratio β. At the same time, the fiber volume fraction FVF

[0062] is also smaller. As G shown, the method for determining the coefficient k and the coefficient b is as follows: Figure 2 S21. Use the least squares method to perform a linear fit on the fabric porosity φ and the fabric compression ratio β to determine the first function. The first function is a function of the fabric compression ratio β with respect to the fabric porosity φ.

[0063] In this step, the first function is β = d×φ + e. The first function is a function of the fabric compression ratio β with respect to the fabric porosity φ. For fabrics of the same specification, the coefficient d of the first function is the same, and the coefficient e of the first function for fabrics of the same specification is also the same.

[0064] S22. Use the least squares method for the fiber volume fraction FVF

[0065] ​G And a linear fitting is performed on the ratio of the fabric compression ratio β to the fabric porosity φ to determine a second function, where the second function is the fiber volume fraction FVF G A function of the fabric compression ratio β and the fabric porosity φ

[0066] In this step, the second function is That is The second function is the fiber volume fraction FVF G A function of the fabric compression ratio β and the fabric porosity φ, where the coefficient a of the same specification fabric is the same, and the coefficient c of the same specification fabric is also the same

[0067] S23. Integrate the first function and the second function to obtain a third function

[0068] S24. Determine the coefficient k and the coefficient b based on the third function and the fabric porosity φ

[0069] In steps S23 and S24, the third function is Integrate the third function with the fabric porosity To obtain the formula The values of the coefficient k and the coefficient b in, where the coefficient k of the same specification fabric is the same, and the coefficient b of the same specification fabric is the same

[0070] Among them, the physical properties of the laminate also include the single-layer thickness CPT (Compressed Ply Thickness) of the fabric in the laminate, with the unit of mm, which is used to characterize the theoretical value of the single-layer thickness of the fabric after being theoretically prepared into a laminate, that is, the single-layer thickness of the fabric in the laminate evaluated based on the relevant values of the fabric, rather than the value obtained by measuring the laminate after actual preparation of the laminate. And h 1 Characterizes the measured value of the single-layer thickness of the fabric in the laminate, which is obtained by measuring the value of the laminate after actual preparation of the laminate, h 1 The value is used to obtain the fabric compression ratio of the laminate made of this specification fabric, that is, the fabric compression ratio of the laminate made of this specification fabric is obtained by preparing a limited number of laminates and measuring relevant data

[0071] The single-layer thickness CPT of the fabric in the laminate can be obtained by obtaining the mass per unit area of ρ A 、The density ρ of the fibers in the fabric G And the fiber volume fraction FVF G To obtain, that is Among them, the mass per unit area of ρ A 、The density ρ of the fibers in the fabric G Are all the values obtained in S1, and the fiber volume fraction FVFG is the value calculated by the formula Based on the preset number of fabric layers n in the laminate, the thickness of the laminate can also be obtained

[0072] In this application, by obtaining relevant and easily measurable data of the fabric, the mass per unit area of the fabric can be quickly determined, and then the physical properties of the laminate can be evaluated, greatly saving the evaluation time and resources. During the evaluation of the physical properties of the laminate, since there is no need for the cumbersome process of conducting a large number of tests on the laminate, the dependence on the finished laminate in the traditional evaluation method is avoided, the time cost in the production and testing links of the laminate is reduced, and the efficiency is improved. Moreover, this application establishes a reliable correlation between the physical properties of the fabric and the physical properties of the laminate, avoiding the errors caused by subjective judgment and empirical estimation, and making the evaluation result of the physical properties of the laminate more accurate.

[0073] The method for preparing a laminate from a fabric in this application is as Figure 3 shown and includes the following steps:

[0074] S31. Humidify the fabric and the resin respectively.

[0075] In step S31, the fabric is made of glass fiber and the resin is epoxy resin. The humidification needs to be carried out under preset conditions, and the preset conditions include a preset temperature, a preset humidity, and a preset time. Among them, the preset temperature is 21°C - 25°C, the range of the preset humidity is 10%RH - 90%RH, and the range of the preset time is 45 hours - 55 hours. Through the humidification treatment, the fabric reaches a suitable and stable humidity condition, which can ensure that the fiber properties of the fabric are in the best state, enhance the adhesion between the fibers of the fabric and the resin, and improve the overall mechanical properties of the laminate.

[0076] S32. Cut the fabric into a fixed shape with a fixed size, and arrange the fabric in the same direction to be laid layer by layer in the mold to form a laid fabric.

[0077] In step S32, through cutting and mold fixation, it helps to control the direction of the mechanical properties of the laminate, and this orderly laying method also facilitates quality control and process management during the production process, improving production efficiency and product repeatability.

[0078] S33. Infuse the resin into the laid fabric to form an infused fabric.

[0079] Before perfusion in step S33, a sealing film is laid on the outside of the mold, and the sealing film is evacuated so that the vacuum degree in the sealing film is a preset vacuum degree, where the range of the preset vacuum degree is 885 mbar - 995 mbar, which can enable the resin to fully infiltrate the fabric fibers and ensure a tight combination between the resin and the fabric.

[0080] S34. The perfused fabric is demolded after being cured by heating to form a laminate.

[0081] The temperature required for heating and curing in step S34 is 75°C - 85°C. This process can be completed in an oven. After curing is completed, the laminate is demolded after it drops below 40°C. A cutting machine can be used to cut the laminate into dimensions convenient for measurement.

[0082] Those of ordinary skill in the art can understand that all or part of the steps in the above method can be completed by instructing relevant hardware through a program. The program can be stored in a computer-readable storage medium, such as a read-only memory, a magnetic disk, or an optical disc, etc. Optionally, all or part of the steps of the above embodiments can also be implemented using one or more integrated circuits. Correspondingly, each module / unit in the above embodiments can be implemented in the form of hardware or in the form of a software functional module. The present invention is not limited to any specific form of combination of hardware and software.

[0083] After considering the specification and practicing the content disclosed herein, those skilled in the art will readily think of other implementation schemes of the present application. The present application aims to cover any variations, uses, or adaptive changes of the present application. These variations, uses, or adaptive changes follow the general principles of the present application and include the common general knowledge or conventional technical means in the technical field not disclosed in the present application. The specification and the embodiments are only regarded as exemplary, and the true scope and spirit of the present application are pointed out by the following claims.

[0084] It should be understood that the present application is not limited to the exact structure already described and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present application is only limited by the appended claims.

Claims

1. A method for evaluating the physical properties of a laminate from the physical properties of a fabric, characterized in that: The steps include: Get the density ρ of the fibers in the fabric G , fabric mass m s , fabric area A and fabric thickness h; Based on the fabric mass m s and the fabric area A, determine the fabric mass per unit area as ρ A ; Based on the mass per unit area ρ A , the density of fibers in the fabric ρ G and fabric thickness h, determine the physical properties of the laminate, wherein the physical properties of the laminate include the fiber volume content FVF of the laminate G and at least one of a single layer thickness CPT of the fabric in the laminate, wherein the laminate is composed of multiple layers of the fabric.

2. The method for evaluating the physical properties of laminates by the physical properties of fabrics according to claim 1, characterized in that: Based on the fabric mass m s and the fabric area A, determine the fabric mass per unit area ρ A ,include: Based on the fabric mass m s and the fabric area A, the mass per unit area of ​​the fabric is obtained as Wherein, the fabric mass m s The unit of is g, and the unit of fabric area A is cm 2 , the mass per unit area ρ A The unit is g / m 2 .

3. The method for evaluating the physical properties of laminates by the physical properties of fabrics according to claim 1, characterized in that: The mass per unit area is ρ A , the density of fibers in the fabric ρ G and fabric thickness h, determine the physical properties of the laminate, including: The fiber volume content of the laminate Among them, ρ G is the density of the fibers in the fabric, in g / cm 3 ,h is the fabric thickness, in mm, ρ A is the mass per unit area, k and b are coefficients, wherein the coefficient k and the coefficient b are related to the fabric porosity φ and the fabric compression ratio β.

4. The method for evaluating the physical properties of laminates by the physical properties of fabrics according to claim 3, characterized in that: The mass per unit area ρ A , the density of fibers in the fabric ρ G and fabric thickness h, determine the physical properties of the laminate, including: The thickness of a single layer of fabric in the laminate ρ A is the mass per unit area, FVF G is the fiber volume content, ρ G is the density of fibers in the fabric, and the unit of the single-layer thickness CPT of the fabric in the laminate is mm.

5. The method for evaluating the physical properties of laminates by the physical properties of fabrics according to claim 3, characterized in that: The method of determining the coefficient k and the coefficient b includes: Based on the mass per unit area ρ A , the density of the fibers in the fabric ρ G and the fabric thickness h, to obtain the fabric porosity φ of the fabric; Get the laminate thickness h G and the number of fabric layers n of the laminate, based on the laminate thickness h G , the number of fabric layers n and the fabric thickness h, determining the fabric compression ratio β of the fabric; Based on the fabric porosity φ, the fabric compression ratio β and the fiber volume content FVF G , determine the coefficient k and the coefficient b.

6. The method for evaluating the physical properties of laminated board by the physical properties of fabric according to claim 5, characterized in that: The method based on the fabric porosity φ, the fabric compression ratio β and the fiber volume content FVF G , determining the coefficient k and the coefficient b, including: Performing linear fitting on the fabric porosity φ and the fabric compression ratio β by using the least square method to determine a first function, where the first function is a function of the fabric compression ratio β with respect to the fabric porosity φ; The fiber volume content FVF is calculated by the least square method. G The ratio of the fabric compression ratio β to the fabric porosity φ is linearly fitted to determine a second function, wherein the second function is the fiber volume content FVF G A function of the fabric compression ratio β and the fabric porosity φ; Merging the first function with the second function to obtain a third function; The coefficient k and the coefficient b are determined based on the third function and the fabric porosity φ.

7. The method for evaluating the physical properties of laminated board by the physical properties of fabric according to claim 5, characterized in that: Based on the laminate thickness h G , the number of fabric layers n and the fabric thickness h, determining the fabric compression ratio β of the fabric, comprising: The thickness of the laminate h G The ratio of the number of fabric layers n is taken as the single-layer thickness measurement value h1 of the fabric in the laminate; The ratio of the single-layer thickness measurement value h1 of the fabric in the laminate to the fabric thickness h is taken as the fabric compression ratio β.

8. The method for evaluating the physical properties of a laminate based on the physical properties of a fabric according to any one of claims 1 to 7, characterized in that: The mass per unit area ρ A Methods for determining include: The fabric mass per unit area of ​​the plurality of fabrics is calculated respectively, and the average value of the plurality of fabric masses per unit area is taken as the mass per unit area ρ A .

9. The method for evaluating the physical properties of a laminate based on the physical properties of a fabric according to any one of claims 1 to 7, characterized in that: The method for preparing the laminate comprises: The fabric and the resin are separately humidified; The fabric is cut into a fixed shape with a fixed size, and the fabric is arranged in the same direction to be laid layer by layer in a mold to form a laid fabric; Infusing the resin into the laid fabric to form an infused fabric; The infused fabric is heated and cured before demoulding to form the laminate.

10. The method for evaluating the physical properties of laminated board by the physical properties of fabric according to claim 9, characterized in that: The method further comprises: Before the pouring, a sealing film is covered on the outside of the mold, and the sealing film is evacuated to make the vacuum degree inside the sealing film reach a preset vacuum degree, wherein the preset vacuum degree ranges from 885 mbar to 995 mbar.

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