Preparation method of microsphere debonding test sample and microsphere debonding test method

Abstract

The invention discloses a preparation method of a microsphere debonding test sample and a microsphere debonding test method. The preparation method comprises the steps that a supporting plate is provided, and a through hole is formed in the supporting plate; the fiber monofilaments are placed on the supporting plate, the fiber monofilaments are bonded to the supporting plate through a bonding agent, and part of the fiber monofilaments are located at the through holes; the melting point of the binder is 125-140 DEG C; coating the resin liquid on the fiber monofilaments at the through holes to form a preset number of resin microspheres on the fiber monofilaments to obtain a prefabricated sample; and curing the prefabricated sample under a preset condition to obtain the microsphere debonding test sample. According to the method, the high-melting-point binder is matched with the fiber monofilament supporting sheet to assist in sample preparation, so that the tolerance of the sample in the sample preparation stage is enhanced, the breakage rate of the test sample in the sample preparation process is reduced, the test cost is reduced, and the sample preparation efficiency is improved; abnormal values are counted, analyzed and eliminated through a Labs test method, and the accuracy and reliability of a test result are ensured.

Description

Technical Field

[0001] The present application relates to the technical field of composite material testing methods, and in particular to a method for preparing a microsphere debonding test sample and a method for testing microsphere debonding. Background Art

[0002] Fiber reinforced polymer (FRP) is a composite material formed by winding, molding or pultrusion of reinforcing fiber materials and resin matrix materials. One of the technical difficulties of fiber reinforced resin composite materials is to ensure the formation of stable and high-strength interface bonding between reinforcing fiber materials and resin matrix materials. Any debonding phenomenon will directly threaten the overall safety and service life of the composite structure.

[0003] In the related technologies, the microsphere debonding test, as a predictive method, can reflect the interface defects between the reinforcing fiber material and the resin matrix material and evaluate the performance decay of the composite material during service. However, its accuracy in simulating the real application environment and the systematic nature of the test method are still insufficient. Summary of the invention

[0004] In order to solve the above technical problems, the present application aims to provide a method for preparing a microsphere debonding test sample and a method for testing microsphere debonding. The microsphere debonding test sample prepared by the method has the advantages of simple sample preparation and high efficiency. When the microsphere debonding test is performed using the microsphere debonding test sample, the test result has high accuracy and reliability.

[0005] According to a first aspect of the present application, a method for preparing a microsphere debonding test sample is provided, comprising:

[0006] Providing a support plate, wherein the support plate is provided with a through hole;

[0007] Placing the fiber monofilaments on the support plate, and bonding the fiber monofilaments to the support plate by means of an adhesive, so that a portion of the fiber monofilaments is located at the through hole; wherein the melting point of the adhesive is 125-140° C.;

[0008] Applying resin liquid on the fiber monofilament located at the through hole to form a preset number of resin microspheres on the fiber monofilament to obtain a prefabricated sample; wherein the diameter of the resin microspheres is 25-85 μm;

[0009] The prefabricated sample is cured under preset conditions to obtain the microsphere debonding test sample.

[0010] In some embodiments of the present application, the binder includes rosin.

[0011] In some embodiments of the present application, the resin liquid includes epoxy resin, curing agent and organic solvent in a weight ratio of 10:0.5-2.0:1.5-2.0.

[0012] In some embodiments of the present application, the preset conditions include:

[0013] In the first stage, the temperature is maintained at 20-30°C for 5-15 minutes;

[0014] The second stage is curing at a temperature of 125-135°C and negative pressure for 65-75 minutes.

[0015] In some embodiments of the present application, bonding the fiber monofilament to the support plate by a bonding agent comprises:

[0016] A bonding point is arranged on the edge of the support plate close to the through hole;

[0017] The fiber filaments are bonded to the support plate via the bonding points.

[0018] In some embodiments of the present application, the middle area of ​​the fiber monofilament is located at the through hole.

[0019] In some embodiments of the present application, before placing the fiber monofilament on the support plate, the preparation method further includes:

[0020] The fiber bundle is dispersed in an organic solvent, dried at a preset temperature, and then a fiber monofilament with a smooth surface is extracted.

[0021] According to a second aspect of the present application, a method for testing the debonding of microspheres is provided, the method comprising:

[0022] Fix the microsphere debonding test sample as described above on the fixture of the tensile testing machine;

[0023] Measuring the diameter value of the fiber monofilament of the microsphere debonding test sample;

[0024] According to the preset test conditions, the resin microspheres are completely peeled off from the fiber monofilaments, and the test data of the breaking strength and the maximum force value of the fiber monofilaments are recorded;

[0025] Based on the first preset configuration information, the abnormal test data is eliminated to obtain the valid data of the maximum force value; wherein the first preset configuration information is the test statistic G and the critical value G of the test data α，n-1 relationship information;

[0026] Based on the second preset configuration information, the interface shear strength between the resin microspheres and the fiber monofilaments is obtained; wherein the second preset configuration information is the corresponding relationship between the interface shear strength, the maximum force value, and the fiber monofilament diameter.

[0027] In some embodiments of the present application, the step of eliminating abnormal test data based on the first preset configuration information includes:

[0028] If the test statistic G of the test data exceeds the critical value G α，n-1 , the test data is regarded as abnormal test data and the abnormal test data is removed.

[0029] In some embodiments of the present application, the test statistic G is calculated according to the following formula:

[0030]

[0031] Wherein, X is the average value of the fracture strength test data of each data point;

[0032] S is the standard deviation of the fracture strength test data of each data point;

[0033] X i is the test data of the breaking strength at any data point;

[0034] n is the number of data points.

[0035] The technical solution provided by this application may have the following beneficial effects:

[0036] In the preparation method of the microsphere debonding test sample of the present application, the auxiliary sample preparation method of the fiber monofilament support sheet with a high melting point binder is used to greatly enhance the tolerance of the sample in the sample preparation stage, reduce the breakage rate of the test sample in the sample preparation process, greatly reduce the test cost and improve the sample preparation efficiency. In the microsphere debonding test method of the present application, the Labs test method is used to statistically analyze and eliminate outliers, ensuring the accuracy and reliability of the test results.

[0037] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0039] Figure 1 The present invention is a flow chart of a method for preparing a microsphere debonding test sample according to an exemplary embodiment.

[0040] Figure 2is a schematic structural diagram of a support plate according to an exemplary embodiment.

[0041] Figure 3 is a flow chart of a method for testing microsphere debonding according to an exemplary embodiment.

[0042] Reference numerals

[0043] 1. Support plate; 11. Through hole; 2. Fiber monofilament; 3. Bonding point. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme of the present application will be clearly and completely described below in combination with the embodiments of the present application and the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present application. It should be noted that, in the absence of conflict, the embodiments in the present application and the features in the embodiments can be arbitrarily combined with each other.

[0045] The present application provides a method for preparing a microsphere debonding test sample, comprising: providing a support plate, the support plate being provided with through holes; placing fiber monofilaments on the support plate, and bonding the fiber monofilaments to the support plate through a binder so that part of the fiber monofilaments are located at the through holes; wherein the melting point of the binder is 125-140°C; applying a resin liquid to the fiber monofilaments located at the through holes to form a preset number of resin microspheres on the fiber monofilaments to obtain a prefabricated sample; wherein the diameter of the resin microspheres is 25-85μm; curing the prefabricated sample under preset conditions to obtain a microsphere debonding test sample. The present application uses a high melting point binder with a melting point of 125-140°C in combination with a fiber monofilament support sheet to greatly enhance the tolerance of the sample in the sample preparation stage, reduce the breakage rate of the test sample during the sample preparation process, greatly reduce the test cost, and improve the sample preparation efficiency.

[0046] Some specific implementation modes described below are intended to facilitate those skilled in the art to understand the present embodiment, and the present embodiment is not limited to some specific implementation modes described below.

[0047] In an exemplary embodiment, referring to Figure 1 , provides a method for preparing a microsphere debonding test sample, comprising:

[0048] S110, providing a support plate, wherein a through hole is provided on the support plate.

[0049] like Figure 2As shown, the support plate 1 can be made of hard cardboard, and the size of the hard cardboard can be 6×3 cm; a circular through hole 11 with a diameter of 2 cm is provided in the center of the support plate 1. The support plate 1 can be placed on a sample rack, and the sample rack can be a "V"-shaped support rack to stably support the support plate 1.

[0050] S120, placing the fiber monofilaments on a support plate, and bonding the fiber monofilaments to the support plate with an adhesive so that part of the fiber monofilaments are located at the through holes; wherein the melting point of the adhesive is 125-140°C.

[0051] In step S120, the fiber monofilament 2 may be, for example, a carbon fiber monofilament, a glass fiber monofilament, etc. Figure 2 As shown, the fiber monofilament 2 is bonded to the support plate 1, and the fiber monofilament 2 is made to span the through hole 11. The melting point of the binder is 125°C. A higher melting point is selected. When the fiber monofilament 2 is cured at high temperature, the fiber monofilament 2 and the support plate 1 still maintain a good bonding strength, which is conducive to maintaining the stability of the bonding of the fiber monofilament 2 and the integrity of the structure. Exemplarily, the melting point of the binder can be 125°C, 130°C, 135°C, and 140°C. The melting point of the binder can also be any melting point between the exemplary melting point values, for example, the melting point of the binder can also be any melting point value between 130-135°C.

[0052] S130, applying the resin liquid on the fiber monofilaments located at the through holes to form a preset number of resin microspheres on the fiber monofilaments to obtain a prefabricated sample; wherein the diameter of the resin microspheres is 25-85 μm.

[0053] In step S130, the resin liquid is applied to the fiber monofilament 2 located at the through hole 11. Under the action of gravity and the surface tension of the resin liquid, a preset number of resin microspheres in a string and spaced apart can be formed on the fiber monofilament 2. The number of resin microspheres is not limited, and can be ten, fifteen, twenty, etc. The resin microspheres with a diameter of 25-85 μm are screened. Exemplarily, the diameters of the resin microspheres are 25 μm, 30 μm, 40 μm, 57 μm, 67 μm, 73 μm, 80 μm, and 85 μm. The diameter of the resin microspheres can be any value between the exemplary diameters, for example, the diameter of the resin microspheres can be any value between 30-57 μm.

[0054] S140, curing the prefabricated sample under preset conditions to obtain a microsphere debonding test sample.

[0055] In step S140, the prefabricated sample is cured under preset conditions to allow the resin to bond with the fiber monofilament 2, so as to obtain a microsphere debonding test sample.

[0056] In an exemplary embodiment, the binder includes rosin.

[0057] In this embodiment, the binder can be a high-melting-point rosin, for example, a rosin with a melting point of 130-135°C. The high-melting-point rosin is selected as the binder. The high-melting-point rosin has a faster curing speed and lower fluidity, and can be quickly cured so that the fiber monofilament 2 is bonded to the support plate 1 to improve the sample preparation efficiency; and the high-melting-point rosin has a melting point of 130-135°C, and can maintain a good bonding strength when the prefabricated sample is cured, effectively avoiding the separation of the fiber monofilament 2 and the support plate 1.

[0058] In an exemplary embodiment, the resin solution includes epoxy resin, curing agent and organic solvent in a weight ratio of 10:0.5-2.0:1.5-2.0.

[0059] In this embodiment, the resin liquid includes epoxy resin, curing agent and organic solvent, wherein the epoxy resin may be, for example, E44 resin, the curing agent may be, for example, triethylenetetramine, and the organic solvent may be, for example, acetone; by adding a small amount of acetone, the fluidity and exhaust effect of the resin liquid can be increased, and the bonding strength between the resin and the fiber monofilament 2 may be avoided to be affected by bubbles in the resin liquid, which is beneficial to reducing the test error. Exemplarily, the weight ratio of the epoxy resin, the curing agent and the organic solvent is 10:0.5:1.5, 10:1.0:1.8, 10:1.5:2.0, 10:2.0:2.0. The weight ratio of the epoxy resin, the curing agent and the organic solvent may also be any ratio between the exemplary ratios, for example, the weight ratio of the epoxy resin, the curing agent and the organic solvent may also be any ratio between 10:1.0-1.5:1.8-2.0.

[0060] In an exemplary embodiment, the preset conditions include:

[0061] In the first stage, the temperature is maintained at 20-30°C for 5-15 minutes;

[0062] The second stage is curing at a temperature of 125-135°C and negative pressure for 65-75 minutes.

[0063] In this embodiment, the prefabricated sample is cured at two temperatures. In the first stage, the prefabricated sample is kept at a temperature of 20-30°C for 5-15 minutes, which allows the resin liquid to initially flow and partially solidify, which is conducive to eliminating bubbles in the resin liquid and maintaining the uniform distribution of resin microspheres. In the second stage, curing is carried out under negative pressure, which can further eliminate residual gas in the prefabricated sample to improve the accuracy of the test results. For example, the prefabricated sample can be placed in a vacuum drying oven, and the vacuum drying oven can be evacuated to a negative pressure, wherein the negative pressure value is not limited, as long as it is lower than the standard atmospheric pressure.

[0064] Exemplarily, in one embodiment, the preset conditions include:

[0065] In the first stage, the temperature was maintained at 20°C for 15 min;

[0066] In the second stage, the curing was carried out at a temperature of 125°C and negative pressure for 75 minutes.

[0067] In another embodiment, the preset conditions include:

[0068] In the first stage, the temperature was maintained at 25°C for 10 min;

[0069] In the second stage, the curing was carried out at a temperature of 130°C and negative pressure for 70 minutes.

[0070] In another embodiment, the preset conditions include:

[0071] In the first stage, the temperature was maintained at 30°C for 5 min;

[0072] In the second stage, the curing was carried out at a temperature of 135°C and negative pressure for 65 minutes.

[0073] In an exemplary embodiment, the fiber monofilaments 2 are bonded to the support plate 1 by a bonding agent, comprising:

[0074] A bonding point 3 is provided at the edge of the support plate 1 close to the through hole 11;

[0075] The fiber filaments 2 are bonded to the support plate 1 via bonding points 3 .

[0076] In this embodiment, the fiber monofilament 2 is bonded to the edge of the support plate 1 near the through hole 11, and the excess portion of the support plate 1 can be removed, leaving only the position of the bonding point 3 and the fiber monofilament-resin microsphere area to facilitate subsequent microsphere debonding testing.

[0077] In an exemplary embodiment, the middle region of the fiber filament 2 is located at the through hole 11 .

[0078] In this embodiment, the middle area of ​​the fiber monofilament 2 is located at the through hole 11, which can improve the stability of the bonding between the fiber monofilament 2 and the support plate 1.

[0079] In an exemplary embodiment, before placing the fiber monofilament 2 on the support plate 1, the preparation method further comprises:

[0080] The fiber bundle is dispersed in an organic solvent, dried at a preset temperature, and then a fiber monofilament 2 with a smooth surface is extracted.

[0081] In this embodiment, the organic solvent may be, for example, acetone. After the fiber bundle is dispersed in acetone, it may be naturally dried at room temperature (20-25° C.), and then the fiber monofilament 2 with a smooth surface may be extracted for testing, thereby avoiding the influence of impurities on the test results.

[0082] like Figure 3 As shown, an exemplary embodiment of the present application provides a method for testing the debonding of microspheres, the testing method comprising:

[0083] S210, fixing the microsphere debonding test sample on the fixture of the tensile testing machine.

[0084] In step S210, the microsphere debonding test sample prepared in the above embodiment is placed in a windless and dust-free environment to naturally cool to room temperature, and then placed on a tensile testing machine and fixed by a clamp.

[0085] S220. Measure the diameter of the fiber monofilament of the microsphere debonding test sample.

[0086] In step S220 , the diameter of the fiber filament 2 may be measured by a digital microscope.

[0087] S230, according to the preset test conditions, the resin microspheres are completely peeled off from the fiber monofilaments 2, and the test data of the breaking strength and the maximum force value of the fiber monofilaments 2 are recorded.

[0088] In step S230 , the preset test condition may be: the clamp is raised at a preset rate (2-30 mm / min) to completely peel off the resin microspheres from the fiber monofilament 2 .

[0089] S240, based on the first preset configuration information, remove abnormal test data to obtain valid data of the maximum force value; wherein the first preset configuration information is the test statistic G and the critical value G of the test data α，n-1 relationship information.

[0090] In step S240, the accuracy of the test result can be improved by eliminating abnormal test data.

[0091] S250. Based on the second preset configuration information, obtain the interface shear strength between the resin microspheres and the fiber monofilaments; wherein the second preset configuration information is the corresponding relationship between the interface shear strength and the maximum force value and the fiber monofilament diameter.

[0092] In step S250, the second preset configuration information may be: calculating the interface shear strength between the resin microspheres and the fiber monofilament 2 according to the following interface shear strength-maximum force value formula (1):

[0093]

[0094] Where, σ is the interfacial shear strength (MPa), i.e., IFSS;

[0095] F is the maximum force value (CN);

[0096] d f is the fiber single filament diameter (μm);

[0097] l e It is the microsphere embedding diameter*1 / 1000(μm).

[0098] In an exemplary embodiment, based on the first preset configuration information, eliminating abnormal test data includes:

[0099] If the test statistic G of the test data exceeds the critical value G α，n-1 , the test data is regarded as abnormal test data and the abnormal test data is removed.

[0100] The test statistic G is calculated according to formula (2):

[0101]

[0102] Wherein, X is the average value of the fracture strength test data of each data point;

[0103] S is the standard deviation of the fracture strength test data of each data point;

[0104] X i is the test data of the breaking strength at any data point;

[0105] n is the number of data points.

[0106] In this embodiment, the Grubbs test method can be applied to further identify and exclude outliers that significantly deviate from the group.

[0107] Exemplarily, the data processing and analysis method of steps S240-S250 may be:

[0108] Calculate the mean value X and standard deviation S of the breaking strength in the test data;

[0109] The test statistic G of each data point is calculated using the Grubbs formula of formula (2);

[0110] Find the critical value G based on the number of data points (with n-1 degrees of freedom) α，n-1 , where α is the set significance level, which can usually be 0.05 or 0.01;

[0111] Compare the test statistics G of each data point. If the test statistic G of the test data exceeds the critical value G α，n-1, the test data is regarded as abnormal test data, and the abnormal test data is eliminated to obtain the valid data of the maximum force value;

[0112] At least ten valid data are collected, and the interface shear strength value between the fiber monofilament 2 and the resin microsphere is calculated according to the interface shear strength-maximum force value formula of formula (1). The coefficient of variation (CV) of the interface shear strength is calculated, and if the CV value is less than 20%, the data is considered valid.

[0113] In order to more clearly explain the technical solution of the present application, the present application lists a method for preparing a microsphere debonding test sample and a specific embodiment of the microsphere debonding test method. The beneficial effects of selecting the above ranges of each parameter will be illustrated by giving specific experimental data through specific embodiments.

[0114] Example

[0115] Unless otherwise specified, the raw materials in the following examples can be obtained from the market. Among them, the E44 epoxy resin can be selected from the bisphenol A epoxy resin with the model number of WSR6101. The binder is selected from the high melting point rosin with a melting point of 130-135°C.

[0116] Example 1: A method for testing the debonding of microspheres, comprising the following steps:

[0117] ① After the carbon fiber tow is dispersed by acetone, it is naturally dried at a temperature of 25°C to extract the fiber monofilament with a smooth surface. Among them, the carbon fiber tow is selected from a certain model of carbon fiber of a Japanese brand, and the tensile strength of the carbon fiber tow is 4900MPa and the modulus is 230GPa.

[0118] ② A bonding point is set on the edge of the support plate near the through hole by using high melting point rosin, the fiber monofilament is bonded to the support plate through the bonding point, and the middle area of ​​the fiber monofilament is located at the through hole.

[0119] ③ Mix E44 epoxy resin, triethylenetetramine and acetone in a weight ratio of 10:1:2 to obtain a resin solution.

[0120] ④ Apply the resin liquid to the fiber monofilament located at the through hole, and under the action of the gravity and surface tension of the resin liquid, a plurality of resin microspheres are formed on the fiber monofilament to obtain a prefabricated sample.

[0121] ⑤ The prefabricated sample was kept at a temperature of 25°C for 10 minutes; then cured at a temperature of 130°C for 70 minutes to obtain a microsphere debonding test sample.

[0122] ⑥ Fix the microsphere debonding test sample on the fixture of the tensile testing machine, select the test sample with a resin microsphere diameter of 30-80 μm, and measure and record the diameter value of the fiber monofilament of the microsphere debonding test sample.

[0123] ⑦ Set the stretching rate to 2 mm / min to completely peel off the resin microspheres from the fiber monofilaments, and record the test data of the breaking strength and maximum force value of the fiber monofilaments.

[0124] ⑧ Use Grubbs formula in formula (2) to calculate the test statistic G for each data point; find the critical value G according to the number of data points (degrees of freedom is n-1) α，n-1 ; Compare the test statistics G of each data point. If the test statistic G of the test data exceeds the critical value G α，n-1 , the test data is regarded as abnormal test data, and the abnormal test data is eliminated to obtain the valid data of the maximum force value.

[0125] ⑨ Collect 10 sets of valid data, and calculate the interface shear strength between the fiber monofilament and the resin microsphere according to the interface shear strength-maximum force value formula of formula (1). Calculate the average value and coefficient of variation (CV) of the valid data, and record the statistical results in Table 1.

[0126] Example 2: This example is basically the same as Example 1, except that the weight ratio of E44 epoxy resin to triethylenetetramine and acetone is 10:1:1.5; the carbon fiber tow is selected from a certain model of carbon fiber CF2 of a Japanese brand, and the tensile strength of the carbon fiber tow is 5490MPa and the modulus is 294GPa.

[0127] Example 3: This example is basically the same as Example 1, except that the carbon fiber tow is selected from a certain model of carbon fiber CF3 of a Korean brand, and the tensile strength of the carbon fiber tow is 4900 MPa and the modulus is 198 GPa.

[0128] Example 4: The difference is that the weight ratio of E44 epoxy resin to triethylenetetramine and acetone is 10:0.5:1.8.

[0129] Example 5: The difference is that the weight ratio of E44 epoxy resin to triethylenetetramine and acetone is 10:1.5:1.5.

[0130] Example 6: The difference is that the weight ratio of E44 epoxy resin to triethylenetetramine and acetone is 10:2.0:1.5.

[0131] Table 1 Test data table of the embodiment

[0132]

[0133] It can be seen from the data in Table 1 that the coefficient of variation CV values ​​of the interfacial shear strength measured in Examples 1-6 are all less than 20%, indicating that when the method of the present application is used to perform microsphere debonding tests, the test results have the advantage of being stable and reliable.

[0134] In summary, the method of the present application can accurately control the sample process and the test process, can effectively evaluate the interface properties of epoxy resin and carbon fiber composite materials, and ensure the accuracy and reliability of the test results.

[0135] It should be noted that, in this article, the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0136] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application is described in detail with reference to the above embodiments, a person skilled in the art should understand that the technical solutions described in the above embodiments can still be modified, or some of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for preparing a microsphere debonding test sample, characterized in that: include: Providing a support plate, wherein the support plate is provided with a through hole; Placing the fiber monofilaments on the support plate, and bonding the fiber monofilaments to the support plate by means of an adhesive, so that a portion of the fiber monofilaments is located at the through hole; wherein the melting point of the adhesive is 125-140° C.; Applying resin liquid on the fiber monofilament located at the through hole to form a preset number of resin microspheres on the fiber monofilament to obtain a prefabricated sample; wherein the diameter of the resin microspheres is 25-85 μm; The prefabricated sample is cured under preset conditions to obtain the microsphere debonding test sample.

2. The method for preparing a microsphere debonding test sample according to claim 1, characterized in that: The binder includes rosin.

3. The method for preparing a microsphere debonding test sample according to claim 1, characterized in that: The resin liquid comprises epoxy resin, curing agent and organic solvent in a weight ratio of 10:0.5-2.0:1.5-2.

0.

4. The method for preparing a microsphere debonding test sample according to claim 1, characterized in that: The preset conditions include: In the first stage, the temperature is maintained at 20-30°C for 5-15 minutes; The second stage is curing at a temperature of 125-135°C and negative pressure for 65-75 minutes.

5. The method for preparing a microsphere debonding test sample according to claim 1, characterized in that: The method comprises bonding the fiber monofilaments to the support plate by a bonding agent, comprising: A bonding point is arranged on the edge of the support plate close to the through hole; The fiber filaments are bonded to the support plate via the bonding points.

6. The method for preparing a microsphere debonding test sample according to claim 1, characterized in that: The middle area of ​​the fiber filament is located at the through hole.

7. The method for preparing a microsphere debonding test sample according to claim 1, characterized in that: Before placing the fiber monofilament on the support plate, the preparation method further comprises: The fiber bundle is dispersed in an organic solvent, dried at a preset temperature, and then a fiber monofilament with a smooth surface is extracted.

8. A method for testing the debonding of microspheres, characterized in that: The test method includes: Fixing the microsphere debonding test sample as described in any one of claims 1 to 7 on the fixture of a tensile testing machine; Measuring the diameter value of the fiber monofilament of the microsphere debonding test sample; According to the preset test conditions, the resin microspheres are completely peeled off from the fiber monofilaments, and the test data of the breaking strength and the maximum force value of the fiber monofilaments are recorded; Based on the first preset configuration information, the abnormal test data is eliminated to obtain the valid data of the maximum force value; wherein the first preset configuration information is the test statistic G and the critical value G of the test data α，n-1 relationship information; Based on the second preset configuration information, the interface shear strength between the resin microspheres and the fiber monofilaments is obtained; wherein the second preset configuration information is the corresponding relationship between the interface shear strength, the maximum force value, and the fiber monofilament diameter.

9. The method for testing the debonding of microspheres according to claim 8, characterized in that: The step of eliminating abnormal test data based on the first preset configuration information includes: If the test statistic G of the test data exceeds the critical value G α，n-1 , the test data is regarded as abnormal test data and the abnormal test data is removed.

10. The method for testing the debonding of microspheres according to claim 8, characterized in that: The test statistic G is calculated according to the following formula: Wherein, X is the average value of the fracture strength test data of each data point; S is the standard deviation of the fracture strength test data of each data point; X i is the test data of the breaking strength at any data point; n is the number of data points.

Images