Tension testing method and system for structural adhesive

Abstract

The invention relates to the technical field of structural adhesive tension testing, in particular to a structural adhesive tension testing method and system. The method comprises the following steps: firstly, acquiring a plurality of tension test base material plates and N tension test environments of a structural adhesive, performing defect detection and roughness detection on the tension test base material plates, screening out qualified tension test base material plates, and constructing a base material data set; secondly, according to the base material data set, obtaining N tension test base material group subsets; thirdly, putting the tension test base material groups in the tension test base material group subsets into corresponding tension test environments, and obtaining the corrected tensile strength of the structural adhesive in each tension test base material group; and finally, according to each corrected tensile strength, obtaining a tension test result of the structural adhesive. According to the method disclosed by the invention, the tension test can be accurately carried out on the structural adhesive.

Description

Technical Field

[0001] The invention relates to the technical field of structural adhesive tensile testing, in particular to a structural adhesive tensile testing method and system. Background Art

[0002] Structural adhesive is an adhesive specifically used for structural bonding. Its main feature is that it can form a strong bonding effect and is used to withstand greater mechanical stress and environmental influences. It is widely used in industrial manufacturing, construction, aerospace and other fields to connect and fix various materials such as metals, plastics, composite materials and glass.

[0003] Before structural adhesives leave the factory, they need to undergo a series of tests, including tensile testing. Tensile testing is an important means of evaluating the performance of structural adhesive bonding joints. This test can ensure that the structural adhesive can achieve the expected strength and durability in actual applications. Therefore, accurate tensile testing of structural adhesives is required.

[0004] In the prior art, most studies on tensile testing of structural adhesives involve coating the structural adhesive between two substrate plates and testing the tensile strength of the structural adhesive by pulling the substrate plates with a universal tensile testing machine. Although the above method can achieve tensile testing of structural adhesives, it fails to take into account the effect of substrate surface treatment on the bonding performance of structural adhesives, which may cause local stress concentration and lead to uneven stress distribution during the tensile test. Such stress concentration may make the tensile test results unrepresentative and reduce the accuracy of the tensile test results of structural adhesives.

[0005] To this end, a tensile testing method and system for structural adhesives are proposed. Summary of the invention

[0006] The object of the present invention is to provide a tensile testing method and system for structural adhesives. First, multiple tensile testing substrate plates and N tensile testing environments of the structural adhesive are collected, and defect detection and roughness detection are performed on the tensile testing substrate plates to screen out qualified tensile testing substrate plates and construct a substrate data set; secondly, based on the substrate data set, N tensile testing substrate group subsets are obtained; thirdly, the tensile testing substrate groups in the tensile testing substrate group subsets are placed in corresponding tensile testing environments to obtain the corrected tensile strength of the structural adhesive in each of the tensile testing substrate groups; finally, based on each of the corrected tensile strengths, the tensile test results of the structural adhesive are obtained.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A tensile test method for a structural adhesive, comprising:

[0009] Collect multiple tensile test substrate panels and N tensile test environments for structural adhesives.

[0010] Furthermore, the dimensions of the tensile test substrate plates are the same; and the first ultimate tensile strength of the tensile test substrate plates satisfies: Among them, qdjx dy Expressed as the first ultimate tensile strength; Expressed as the ultimate tensile strength coefficient, qxD de It represents the second ultimate tensile strength corresponding to the set structural adhesive; the tensile test substrate plate is divided into a structural adhesive coating surface and a universal tensile machine contact surface.

[0011] Furthermore, based on the environmental data in the tensile test environment database, N tensile test environments are obtained; the humidity and temperature of the N tensile test environments are different; the tensile test environment database is acquired in advance; the tensile test environment database contains multiple tensile test environment parameter groups; each of the tensile test environment parameter groups includes the humidity and temperature of the tensile test environment.

[0012] Defect detection and roughness detection are performed on the tensile test substrate plates, qualified tensile test substrate plates are screened out, and a substrate data set is constructed.

[0013] Furthermore, the process of obtaining the qualified tensile test substrate plate includes:

[0014] Acquire a surface image of the tensile test substrate plate, the surface image comprising a first surface image of the structural adhesive coating surface and a second surface image of the universal tensile machine contact surface;

[0015] Performing defect detection on the first surface image and the second surface image to obtain defect detection results;

[0016] The defect detection result includes whether there are cracks, whether there are dents, whether there are grease and whether there is corrosion; when the defect detection result is no cracks, no dents, no grease and no corrosion, the roughness of the structural adhesive coating surface of the tensile test substrate plate is detected; otherwise, the tensile test substrate plate is an unqualified tensile test substrate plate;

[0017] When the roughness test result is unqualified, the tensile test substrate plate is an unqualified tensile test substrate plate; otherwise, the tensile test substrate plate is a qualified tensile test substrate plate, and the surface roughness of the structural adhesive coating surface of the qualified tensile test substrate plate is obtained.

[0018] Furthermore, the roughness detection includes:

[0019] The structural adhesive coating surface of each tensile test substrate plate is divided into M sub-areas, and the arithmetic mean deviation of the contour of each sub-area is detected; according to the arithmetic mean deviation of the contour of the M sub-areas, the roughness detection value of the structural adhesive coating surface is obtained, and the calculation formula is:

[0020]

[0021] Among them, ztcc i Ra is the roughness test value of the structural adhesive coating surface of the i-th tensile test substrate plate; (i,j) Represented as ztcc i The arithmetic mean deviation of the contour of the corresponding j-th sub-region; Ra bz Expressed as the set standard deviation value; Var i Expressed as the variance of the arithmetic mean deviation of the contours of M sub-regions; α 1 Expressed as the first roughness coefficient; α 2 Expressed as the second roughness coefficient;

[0022] When the roughness detection value is less than the set roughness standard value, the roughness detection result is qualified; otherwise, the roughness detection result is unqualified.

[0023] According to the substrate data set, N tensile test substrate group subsets are obtained.

[0024] Furthermore, the acquisition process of the tensile test substrate group includes: dividing the tensile test substrate plates in the substrate data set into first tensile test substrate plates and second tensile test substrate plates; the number of the first tensile test substrate plates and the second tensile test substrate plates are equal;

[0025] Applying the same structural adhesive between the first tensile test substrate plate and the second tensile test substrate plate to bond the first tensile test substrate plate and the second tensile test substrate plate to obtain a plurality of tensile test substrate groups; the coating thickness of the structural adhesive is a fixed value;

[0026] The plurality of tensile test substrate groups are divided into N tensile test substrate group subsets.

[0027] The tensile test substrate groups in the tensile test substrate group subset are placed in a corresponding tensile test environment to obtain the modified tensile strength of the structural adhesive in each of the tensile test substrate groups.

[0028] Furthermore, the process of obtaining the modified tensile strength includes: obtaining the coating area of ​​the structural adhesive between the first tensile test substrate plate and the second tensile test substrate plate before each tensile test substrate group is placed in the corresponding tensile test environment; after each tensile test substrate group is placed in the corresponding tensile test environment for T time, using a universal tensile testing machine to obtain the ultimate tensile force of each tensile test substrate group;

[0029] The modified tensile strength of the structural adhesive corresponding to each tensile test substrate group is obtained according to the ultimate tensile force, and the calculation formula of the modified tensile strength is:

[0030]

[0031] Among them, xzkl (h,j) It is expressed as the modified tensile strength of the structural adhesive corresponding to the jth tensile test substrate group in the hth tensile test environment; jxll (h,j) Represented as xzkl (h,j) Corresponding ultimate tensile force; tfmj (h,j) Represented as xzkl (h,j) Corresponding coating area; hjwd h It is expressed as the ambient temperature of the hth tensile test environment; hjsd h It is represented by the ambient humidity of the hth tensile test environment; f() is represented by a nonlinear analytical function; ccd (h,j) It is expressed as the average surface roughness of the two tensile test substrates in the jth tensile test substrate group in the hth tensile test environment; CCD bz Expressed as standard roughness; χ 0 Expressed as tensile strength coefficient; χ 1 Expressed as environmental coefficient; χ 2 It is expressed as the roughness coefficient; exp() is expressed as an exponential function with a natural constant as the base.

[0032] According to each of the modified tensile strengths, a tensile test result of the structural adhesive is obtained.

[0033] Furthermore, the tensile test result is a tensile test pass rate of the structural adhesive under N tensile test environments, and the specific acquisition process includes:

[0034] The tensile test substrate group whose corrected tensile strength is less than the set minimum standard tensile strength is recorded as a tensile test unqualified substrate group; otherwise, the tensile test substrate group is recorded as a tensile test qualified substrate group;

[0035] The proportion of the substrate groups that pass the tensile test in each tensile test environment is obtained, and the proportion is recorded as the tensile test pass rate.

[0036] A tensile testing system for structural adhesives, comprising:

[0037] A collection unit, used for collecting a plurality of tensile test substrate plates and N tensile test environments of the structural adhesive;

[0038] A tensile test substrate plate screening unit is used to perform defect detection and roughness detection on the tensile test substrate plate, screen out qualified tensile test substrate plates, and construct a substrate data set;

[0039] A tensile test substrate group subset acquisition unit, used to acquire N tensile test substrate group subsets according to the substrate data set;

[0040] A modified tensile strength acquisition unit, used for placing the tensile test substrate groups in the tensile test substrate group subset into a corresponding tensile test environment, and acquiring the modified tensile strength of the structural adhesive in each of the tensile test substrate groups;

[0041] The tensile test result acquisition unit is used to acquire the tensile test result of the structural adhesive according to each of the modified tensile strengths.

[0042] Furthermore, the process of obtaining the qualified tensile test substrate plate includes: obtaining a surface image of the tensile test substrate plate, the surface image including a first surface image of the structural adhesive coating surface and a second surface image of the contact surface of the universal tensile machine; performing defect detection on the first surface image and the second surface image to obtain defect detection results; the defect detection results include whether it contains cracks, whether it contains depressions, whether it contains grease, and whether it contains corrosion; when the defect detection results are no cracks, no depressions, no grease, and no corrosion, performing a roughness detection on the structural adhesive coating surface of the tensile test substrate plate; otherwise, the tensile test substrate plate is an unqualified tensile test substrate plate; when the roughness detection result is unqualified, the tensile test substrate plate is an unqualified tensile test substrate plate; otherwise, the tensile test substrate plate is a qualified tensile test substrate plate, and the surface roughness of the structural adhesive coating surface of the qualified tensile test substrate plate is obtained.

[0043] Furthermore, the roughness detection includes:

[0044] The structural adhesive coating surface of each tensile test substrate plate is divided into M sub-areas, and the arithmetic mean deviation of the contour of each sub-area is detected; according to the arithmetic mean deviation of the contour of the M sub-areas, the roughness detection value of the structural adhesive coating surface is obtained, and the calculation formula is:

[0045]

[0046] Among them, ztcc i Ra is the roughness test value of the structural adhesive coating surface of the i-th tensile test substrate plate; (i,j) Represented as ztcc i The arithmetic mean deviation of the contour of the corresponding j-th sub-region; Ra bz Expressed as the set standard deviation value; Var i Expressed as the variance of the arithmetic mean deviation of the contours of M sub-regions; α 1 Expressed as the first roughness coefficient; α 2 It is expressed as a second roughness coefficient; when the roughness detection value is less than the set roughness standard value, the roughness detection result is qualified; otherwise, the roughness detection result is unqualified.

[0047] Furthermore, the tensile test environment includes: N tensile test environments having different humidity and temperature.

[0048] Compared with the prior art, the present invention has the following beneficial effects:

[0049] 1. The surface defects and roughness of the tensile test substrate plate will affect the tensile test results of the structural adhesive. The present invention performs defect detection and roughness detection on the tensile test substrate plate, and removes the tensile test substrate plates with cracks, dents, grease, corrosion and unqualified roughness. This method can avoid the tensile test of the structural adhesive being affected by defects and unqualified roughness on the surface of the tensile test substrate plate, thereby improving the accuracy of the tensile test of the structural adhesive.

[0050] 2. When the present invention detects the roughness of the tensile test substrate plate, the arithmetic mean deviation of the contours of different sub-regions on the structural adhesive coating surface of the tensile test substrate plate is first obtained, and then the roughness detection value of the structural adhesive coating surface is obtained based on the arithmetic mean deviation of the contours. This method can fully understand the surface characteristics of the substrate, ensure that the overall and local roughness of the structural adhesive coating surface are consistent, and thus improve the accuracy and reliability of subsequent structural adhesive tensile testing.

[0051] 3. The tensile test results of the structural adhesive are also affected by the humidity and temperature in the test environment. The present invention sets up multiple tensile test environments for different humidity and temperature, and detects the corrected tensile strength of the structural adhesive under different tensile test environments. The corrected tensile strength can correct the tensile strength of the structural adhesive according to the tensile test environment and the surface roughness of the tensile test substrate, so as to accurately obtain the tensile test results of the structural adhesive under different tensile test environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1A flow chart of a tensile testing method for a structural adhesive provided by an embodiment of the present invention;

[0053] Figure 2 A structural diagram of a tensile testing system for a structural adhesive provided by an embodiment of the present invention;

[0054] Figure 3 A flow chart for obtaining a qualified tensile test substrate plate provided by an embodiment of the present invention;

[0055] Figure 4 A schematic diagram of a roughness detection process provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0056] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0057] Structural adhesive is an adhesive specifically used for structural bonding. Its main feature is that it can form a strong bonding effect and is used to withstand greater mechanical stress and environmental influences. It is widely used in industrial manufacturing, construction, aerospace and other fields to connect and fix various materials such as metals, plastics, composite materials and glass.

[0058] Before structural adhesives leave the factory, they need to undergo a series of tests, including tensile testing. Tensile testing is an important means of evaluating the performance of structural adhesive bonding joints. This test can ensure that the structural adhesive can achieve the expected strength and durability in actual applications. Therefore, accurate tensile testing of structural adhesives is required.

[0059] To this end, the present invention provides a tensile test method for a structural adhesive, which is applied to a tensile test system for a structural adhesive. The specific method flow chart and system structure diagram refer to Figure 1 and Figure 2 .

[0060] Embodiment 1

[0061] Reference Figure 1 The S10 in FIG. 1 is applied to the collection unit of a tensile test system for structural adhesives.

[0062] Furthermore, the tensile test substrate plates have the same size, which includes the same length, the same width and the same thickness; and the first ultimate tensile strength of the tensile test substrate plates satisfies: Among them, qdjx dyExpressed as the first ultimate tensile strength; Expressed as the ultimate tensile strength coefficient, qxD de It represents the second ultimate tensile strength corresponding to the set structural adhesive; the tensile test substrate plate is divided into a structural adhesive coating surface and a universal tensile machine contact surface; the material of the tensile test substrate plate can be titanium alloy, carbon steel, etc.

[0063] This step of the present embodiment limits the ultimate tensile strength of the tensile test substrate plate according to the ultimate tensile strength of the structural adhesive, so as to ensure that the tensile test substrate plate will not be broken during the tensile test of the structural adhesive, thereby avoiding the influence of premature breakage of the tensile test substrate plate on the tensile test results, and thus improving the accuracy of the structural adhesive tensile test.

[0064] Furthermore, based on the environmental data in the tensile test environment database, N tensile test environments are obtained; the tensile test environment database is obtained in advance; the tensile test environment database contains multiple tensile test environment parameter groups; each of the tensile test environment parameter groups includes the humidity and temperature of the tensile test environment; this embodiment obtains five tensile test environment parameter groups, and five tensile test environments are obtained based on the five tensile test environment parameter groups, and the five tensile test environments only differ in humidity and temperature; the data of the five tensile test environment parameter groups refer to Table 1.

[0065] Table 1 Tensile test environmental parameter group data table

[0066] Serial number 1 2 3 4 5 temperature 5℃ 5℃ 25℃ 75℃ 75℃ humidity 20％ 80％ 50％ 20％ 80％

[0067] The tensile test results of structural adhesives are also affected by the ambient temperature and humidity. In this embodiment, multiple tensile test environments are set according to the different temperatures and humidity. This method can provide different environments for subsequent tensile tests of structural adhesives. By detecting the tensile test results of structural adhesives in different environments, the actual performance of adhesives under different environmental conditions can be fully understood, ensuring their reliability and stability in various applications.

[0068] Reference Figure 1 The S20 in the S20 is a tensile test substrate plate screening unit for a tensile test system for structural adhesives.

[0069] Further, refer to Figure 3 The process of obtaining the qualified tensile test substrate plate includes:

[0070] Acquire a surface image of the tensile test substrate plate, the surface image comprising a first surface image of the structural adhesive coating surface and a second surface image of the universal tensile machine contact surface;

[0071] Performing defect detection on the first surface image and the second surface image to obtain defect detection results;

[0072] The defect detection result includes whether there are cracks, depressions, grease and corrosion; when the defect detection result is no cracks, no depressions, no grease and no corrosion, the roughness of the structural adhesive coating surface of the tensile test substrate plate is detected; otherwise, the tensile test substrate plate is an unqualified tensile test substrate plate; when the roughness detection result is unqualified, the tensile test substrate plate is an unqualified tensile test substrate plate; otherwise, the tensile test substrate plate is a qualified tensile test substrate plate, and the surface roughness of the structural adhesive coating surface of the qualified tensile test substrate plate is obtained; the surface roughness is the arithmetic mean deviation of the contour of the entire structural adhesive coating surface.

[0073] This step of the present embodiment performs defect detection and roughness detection on the tensile test substrate plate. If the substrate plate has appearance defects, the structural adhesive may not be able to fully cover and adhere to the defective area, thereby affecting the overall tensile test results. If the roughness of the substrate is uneven, the structural adhesive may not adhere well in certain areas, thereby affecting the overall tensile test results. This embodiment can eliminate tensile test substrate plates with unqualified appearance and roughness through defect detection and roughness detection, thereby improving the accuracy of the structural adhesive tensile test.

[0074] Further, refer to Figure 4 The roughness detection includes: dividing the structural adhesive coating surface of each tensile test substrate plate into M sub-areas, and detecting the arithmetic mean deviation of the contour of each sub-area; according to the arithmetic mean deviation of the contour of the M sub-areas, obtaining the roughness detection value of the structural adhesive coating surface, and the calculation formula is:

[0075]

[0076] Among them, ztcc i Ra is the roughness test value of the structural adhesive coating surface of the i-th tensile test substrate plate; (i,j) Represented as ztcc i The arithmetic mean deviation of the contour of the corresponding j-th sub-region; Ra bz Indicated as the set standard deviation value; in this embodiment, Ra bz Set to 54, which can be changed according to the specific implementation in actual application; Var i Expressed as the variance of the arithmetic mean deviation of the contours of M sub-regions; α 1 Expressed as the first roughness coefficient; α2 Expressed as the second roughness coefficient; α 1 and α 2 The default value of is 0.5, which can be changed according to the specific implementation situation in actual application;

[0077] When the roughness detection value is less than the set roughness standard value, the roughness detection result is qualified; otherwise, the roughness detection result is unqualified; in this embodiment, the roughness standard value is set to 5, which can also be changed according to specific implementation conditions in actual applications.

[0078] In this step of the present embodiment, when the roughness of the tensile test substrate is detected, the arithmetic mean deviation of the contours of different sub-regions on the structural adhesive coating surface of the tensile test substrate is first obtained, and then the roughness detection value of the structural adhesive coating surface is obtained based on the arithmetic mean deviation of the contours. This method can fully understand the surface characteristics of the substrate, ensure that the overall and local roughness of the structural adhesive coating surface are consistent, and thus improve the accuracy and reliability of subsequent structural adhesive tensile testing.

[0079] Furthermore, the present embodiment divides the structural adhesive coating surface of each tensile test substrate plate into six sub-areas. The present embodiment obtains the arithmetic mean deviation of the contour of each sub-area; obtains the roughness detection value of the structural adhesive coating surface based on the arithmetic mean deviation of the contour of the M sub-areas, and judges the roughness detection result based on the roughness detection value. The present embodiment shows the roughness detection results of five tensile test substrate plates, with specific reference to Table 2 and Table 3, wherein Table 2 gives the arithmetic mean deviation of the contour of each sub-area of ​​the five tensile test substrate plates; Table 3 gives the roughness detection results of the five tensile test substrate plates.

[0080] Table 2 Arithmetic mean deviation of contour

[0081]

[0082] Table 3 Roughness test results

[0083] Serial number Roughness test value Rough standard value Roughness test results 1 2.43 5 qualified 2 11.54 5 Failure 3 2.94 5 qualified 4 2.85 5 qualified 5 9.16 5 Failure

[0084] Reference Figure 1 S30 in which S30 is applied to a tensile test substrate group subset acquisition unit of a tensile test system for a structural adhesive.

[0085] Furthermore, the acquisition process of the tensile test substrate group includes: dividing the tensile test substrate plates in the substrate data set into first tensile test substrate plates and second tensile test substrate plates; the number of the first tensile test substrate plates and the second tensile test substrate plates are equal;

[0086] Applying the same structural adhesive between the first tensile test substrate plate and the second tensile test substrate plate to bond the first tensile test substrate plate and the second tensile test substrate plate to obtain a plurality of tensile test substrate groups; the coating thickness of the structural adhesive is a fixed value;

[0087] The plurality of tensile test substrate groups are divided into N tensile test substrate group subsets.

[0088] This step of the present embodiment obtains multiple tensile test substrate groups based on the tensile test substrate plate, and divides the multiple tensile test substrate groups into N tensile test substrate group subsets, providing a basis for subsequently obtaining tensile test results of structural adhesives in different environments, and ensuring that the coating thickness of the structural adhesive is a fixed value to avoid the tensile test results of the structural adhesive being affected by inconsistent coating thickness, thereby improving the accuracy and reliability of structural adhesive tensile testing.

[0089] Reference Figure 1 S40 in the S40, S40 is applied to a modified tensile strength acquisition unit of a tensile testing system for structural adhesives.

[0090] Furthermore, the process of obtaining the modified tensile strength includes: obtaining the coating area of ​​the structural adhesive between the first tensile test substrate plate and the second tensile test substrate plate before each tensile test substrate group is placed in the corresponding tensile test environment; after each tensile test substrate group is placed in the corresponding tensile test environment for T time, using a universal tensile testing machine to obtain the ultimate tensile force of each tensile test substrate group;

[0091] The modified tensile strength of the structural adhesive corresponding to each tensile test substrate group is obtained according to the ultimate tensile force, and the calculation formula of the modified tensile strength is:

[0092]

[0093] Among them, xzkl (h,j) It is expressed as the modified tensile strength of the structural adhesive corresponding to the jth tensile test substrate group in the hth tensile test environment; jxll (h,j) Represented as xzkl (h,j) Corresponding ultimate tensile force; tfmj (h,j) Represented as xzkl (h,j) Corresponding coating area; hjwd h It is expressed as the ambient temperature of the hth tensile test environment; hjsd h It is represented by the ambient humidity of the hth tensile test environment; f() is represented by a nonlinear analytical function; ccd (h,j)It is expressed as the average surface roughness of the two tensile test substrates in the jth tensile test substrate group in the hth tensile test environment; CCD bz Expressed as standard roughness; χ 0 Expressed as tensile strength coefficient; χ 1 Expressed as environmental coefficient; χ 2 Expressed as roughness coefficient; χ 0 , χ 1 and χ 2 It is obtained through training with a large amount of historical data; exp() is expressed as an exponential function with a natural constant as the base.

[0094] The tensile test results of the structural adhesive are also affected by the humidity and temperature in the test environment. In this step of the present embodiment, multiple tensile test environments are set according to different humidity and temperature, and the corrected tensile strength of the structural adhesive under different tensile test environments is detected. The corrected tensile strength can correct the tensile strength of the structural adhesive according to the tensile test environment and the surface roughness of the tensile test substrate, so as to accurately obtain the tensile test results of the structural adhesive under different tensile test environments.

[0095] Reference Figure 1 S50 in the embodiment is applied to a tensile test result acquisition unit of a tensile test system for a structural adhesive.

[0096] Furthermore, the tensile test result is a tensile test pass rate of the structural adhesive under N tensile test environments, and the specific acquisition process includes:

[0097] The tensile test substrate group whose corrected tensile strength is less than the set minimum standard tensile strength is recorded as a tensile test unqualified substrate group; otherwise, the tensile test substrate group is recorded as a tensile test qualified substrate group;

[0098] The proportion of the substrate groups that pass the tensile test in each tensile test environment is obtained, and the proportion is recorded as the tensile test pass rate.

[0099] Furthermore, the tensile test pass rates of the structural adhesive in five tensile test environments obtained in this embodiment are 100%, 98.21%, 100%, 99.11% and 98.21% respectively.

[0100] This step of the present embodiment obtains the tensile test pass rate of the structural adhesive under N tensile test environments based on the corrected tensile strength. This method can accurately evaluate the actual performance of the structural adhesive under different tensile test environments to ensure its reliability and stability in various applications.

[0101] Embodiment 2

[0102] In Example 1, the method of the present invention is combined with the system to implement the tensile test of the structural adhesive; the method of the present invention will be described again in the embodiment of this application, and the specific implementation process includes:

[0103] Collect multiple tensile test substrate panels and N tensile test environments for structural adhesives.

[0104] Furthermore, the dimensions of the tensile test substrate plates are the same; and the first ultimate tensile strength of the tensile test substrate plates satisfies: Among them, qdjx dy Expressed as the first ultimate tensile strength; Expressed as the ultimate tensile strength coefficient, qxD de It represents the second ultimate tensile strength corresponding to the set structural adhesive; the tensile test substrate plate is divided into a structural adhesive coating surface and a universal tensile machine contact surface.

[0105] Furthermore, based on the environmental data in the tensile test environment database, N tensile test environments are obtained; the humidity and temperature of the N tensile test environments are different; the tensile test environment database is acquired in advance; the tensile test environment database contains multiple tensile test environment parameter groups; each of the tensile test environment parameter groups includes the humidity and temperature of the tensile test environment.

[0106] Defect detection and roughness detection are performed on the tensile test substrate plates, qualified tensile test substrate plates are screened out, and a substrate data set is constructed.

[0107] Furthermore, the process of obtaining the qualified tensile test substrate plate includes:

[0108] Acquire a surface image of the tensile test substrate plate, the surface image comprising a first surface image of the structural adhesive coating surface and a second surface image of the universal tensile machine contact surface;

[0109] Performing defect detection on the first surface image and the second surface image to obtain defect detection results;

[0110] The defect detection result includes whether there are cracks, whether there are dents, whether there are grease and whether there is corrosion; when the defect detection result is no cracks, no dents, no grease and no corrosion, the roughness of the structural adhesive coating surface of the tensile test substrate plate is detected; otherwise, the tensile test substrate plate is an unqualified tensile test substrate plate;

[0111] When the roughness test result is unqualified, the tensile test substrate plate is an unqualified tensile test substrate plate; otherwise, the tensile test substrate plate is a qualified tensile test substrate plate, and the surface roughness of the structural adhesive coating surface of the qualified tensile test substrate plate is obtained.

[0112] Furthermore, the roughness detection includes:

[0113] The structural adhesive coating surface of each tensile test substrate plate is divided into M sub-areas, and the arithmetic mean deviation of the contour of each sub-area is detected; according to the arithmetic mean deviation of the contour of the M sub-areas, the roughness detection value of the structural adhesive coating surface is obtained, and the calculation formula is:

[0114]

[0115] Among them, ztcc i Ra is the roughness test value of the structural adhesive coating surface of the i-th tensile test substrate plate; (i,j) Represented as ztcc i The arithmetic mean deviation of the contour of the corresponding j-th sub-region; Ra bz Expressed as the set standard deviation value; Var i Expressed as the variance of the arithmetic mean deviation of the contours of M sub-regions; α 1 Expressed as the first roughness coefficient; α 2 Expressed as the second roughness coefficient;

[0116] When the roughness detection value is less than the set roughness standard value, the roughness detection result is qualified; otherwise, the roughness detection result is unqualified.

[0117] According to the substrate data set, N tensile test substrate group subsets are obtained.

[0118] Furthermore, the acquisition process of the tensile test substrate group includes: dividing the tensile test substrate plates in the substrate data set into first tensile test substrate plates and second tensile test substrate plates; the number of the first tensile test substrate plates and the second tensile test substrate plates are equal;

[0119] Applying the same structural adhesive between the first tensile test substrate plate and the second tensile test substrate plate to bond the first tensile test substrate plate and the second tensile test substrate plate to obtain a plurality of tensile test substrate groups; the coating thickness of the structural adhesive is a fixed value;

[0120] The plurality of tensile test substrate groups are divided into N tensile test substrate group subsets.

[0121] The tensile test substrate groups in the tensile test substrate group subset are placed in a corresponding tensile test environment to obtain the modified tensile strength of the structural adhesive in each of the tensile test substrate groups.

[0122] Furthermore, the process of obtaining the modified tensile strength includes: obtaining the coating area of ​​the structural adhesive between the first tensile test substrate plate and the second tensile test substrate plate before each tensile test substrate group is placed in the corresponding tensile test environment; after each tensile test substrate group is placed in the corresponding tensile test environment for T time, using a universal tensile testing machine to obtain the ultimate tensile force of each tensile test substrate group;

[0123] The modified tensile strength of the structural adhesive corresponding to each tensile test substrate group is obtained according to the ultimate tensile force, and the calculation formula of the modified tensile strength is:

[0124]

[0125] Among them, xzkl (h,j) It is expressed as the modified tensile strength of the structural adhesive corresponding to the jth tensile test substrate group in the hth tensile test environment; jxll (h,j) Represented as xzkl (h,j) Corresponding ultimate tensile force; tfmj (h,j) Represented as xzkl (h,j) Corresponding coating area; hjwd h It is expressed as the ambient temperature of the hth tensile test environment; hjsd h It is represented by the ambient humidity of the hth tensile test environment; f() is represented by a nonlinear analytical function; ccd (h,j) It is expressed as the average surface roughness of the two tensile test substrates in the jth tensile test substrate group in the hth tensile test environment; CCD bz Expressed as standard roughness; χ 0 Expressed as tensile strength coefficient; χ 1 Expressed as environmental coefficient; χ 2 It is expressed as the roughness coefficient; exp() is expressed as an exponential function with a natural constant as the base.

[0126] According to each of the modified tensile strengths, a tensile test result of the structural adhesive is obtained.

[0127] Furthermore, the tensile test result is a tensile test pass rate of the structural adhesive under N tensile test environments, and the specific acquisition process includes:

[0128] The tensile test substrate group whose corrected tensile strength is less than the set minimum standard tensile strength is recorded as a tensile test unqualified substrate group; otherwise, the tensile test substrate group is recorded as a tensile test qualified substrate group;

[0129] The proportion of the substrate groups that pass the tensile test in each tensile test environment is obtained, and the proportion is recorded as the tensile test pass rate.

[0130] The surface defects and roughness of the tensile test substrate plate will affect the tensile test results of the structural adhesive. In this embodiment, the tensile test substrate plate is subjected to defect detection and roughness detection, and the tensile test substrate plates with cracks, dents, grease, corrosion and unqualified roughness are eliminated. This method can avoid the tensile test of the structural adhesive being affected due to defects and unqualified roughness on the surface of the tensile test substrate plate, thereby improving the accuracy of the tensile test of the structural adhesive. When the tensile test substrate plate is subjected to roughness detection in this embodiment, the arithmetic mean deviation of the contours of different sub-areas on the structural adhesive coating surface of the tensile test substrate plate is first obtained, and then the roughness detection value of the structural adhesive coating surface is obtained based on the arithmetic mean deviation of the contours. This method can fully understand the surface characteristics of the substrate, ensure that the overall and local roughness of the structural adhesive coating surface are consistent, and thereby improve the accuracy and reliability of subsequent structural adhesive tensile detection. The tensile test results of the structural adhesive are also affected by the humidity and temperature in the test environment. In this embodiment, multiple tensile test environments are set according to different humidity and temperature, and the corrected tensile strength of the structural adhesive under different tensile test environments is detected. The corrected tensile strength can correct the tensile strength of the structural adhesive according to the tensile test environment and the surface roughness of the tensile test substrate, so as to accurately obtain the tensile test results of the structural adhesive under different tensile test environments.

[0131] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A tensile test method for a structural adhesive, characterized in that: include: Collect multiple tensile test substrate plates and N tensile test environments of structural adhesives; Performing defect detection and roughness detection on the tensile test substrate plate, screening out qualified tensile test substrate plates, and constructing a substrate data set; The roughness detection includes: dividing the structural adhesive coating surface of each tensile test substrate plate into M sub-areas, and detecting the arithmetic mean deviation of the contour of each sub-area; according to the arithmetic mean deviation of the contour of the M sub-areas, obtaining the roughness detection value of the structural adhesive coating surface, and the calculation formula is: Among them, ztcc i Ra is the roughness test value of the structural adhesive coating surface of the i-th tensile test substrate plate; (i,j) Represented as ztcc i The arithmetic mean deviation of the contour of the corresponding j-th sub-region; Ra bz Expressed as the set standard deviation value; Var i It is represented as the variance of the arithmetic mean deviation of the contours of the M sub-regions; α1 is represented as the first roughness coefficient; α2 is represented as the second roughness coefficient; When the roughness detection value is less than the set roughness standard value, the roughness detection result is qualified; otherwise, the roughness detection result is unqualified; According to the substrate data set, obtaining N tensile test substrate group subsets; placing the tensile test substrate groups in the tensile test substrate group subset into a corresponding tensile test environment, and obtaining the modified tensile strength of the structural adhesive in each of the tensile test substrate groups; According to each of the modified tensile strengths, a tensile test result of the structural adhesive is obtained.

2. A tensile test method for a structural adhesive according to claim 1, characterized in that: The tensile test substrate plates include: the dimensions of the tensile test substrate plates are the same; the first ultimate tensile strength of the tensile test substrate plates satisfies: Among them, qdjx dy Expressed as the first ultimate tensile strength; Expressed as the ultimate tensile strength coefficient, qxD de It represents the second ultimate tensile strength corresponding to the set structural adhesive; the tensile test substrate plate is divided into a structural adhesive coating surface and a universal tensile machine contact surface.

3. A tensile test method for a structural adhesive according to claim 1, characterized in that: The tensile test environment includes: N tensile test environments having different humidity and temperature.

4. A tensile test method for a structural adhesive according to claim 1, characterized in that: The process of obtaining the qualified tensile test substrate plate includes: Acquire a surface image of the tensile test substrate plate, the surface image comprising a first surface image of the structural adhesive coating surface and a second surface image of the universal tensile machine contact surface; Performing defect detection on the first surface image and the second surface image to obtain defect detection results; The defect detection result includes whether there are cracks, depressions, grease and corrosion; when the defect detection result is that there are no cracks, no depressions, no grease and no corrosion, the roughness of the structural adhesive coating surface of the tensile test substrate plate is detected; otherwise, the tensile test substrate plate is an unqualified tensile test substrate plate; when the roughness detection result is unqualified, the tensile test substrate plate is an unqualified tensile test substrate plate; otherwise, the tensile test substrate plate is a qualified tensile test substrate plate, and the surface roughness of the structural adhesive coating surface of the qualified tensile test substrate plate is obtained.

5. The tensile test method of a structural adhesive according to claim 1, characterized in that: The acquisition process of the tensile test substrate group includes: dividing the tensile test substrate plates in the substrate data set into first tensile test substrate plates and second tensile test substrate plates; the number of the first tensile test substrate plates and the number of the second tensile test substrate plates are equal; Applying the same structural adhesive between the first tensile test substrate plate and the second tensile test substrate plate to bond the first tensile test substrate plate and the second tensile test substrate plate to obtain a plurality of tensile test substrate groups; the coating thickness of the structural adhesive is a fixed value; The plurality of tensile test substrate groups are divided into N tensile test substrate group subsets.

6. A tensile test method for a structural adhesive according to claim 1, characterized in that: The process of obtaining the modified tensile strength includes: obtaining the coating area of ​​the structural adhesive between the first tensile test substrate plate and the second tensile test substrate plate before each tensile test substrate group is placed in the corresponding tensile test environment; after each tensile test substrate group is placed in the corresponding tensile test environment for T time, using a universal tensile testing machine to obtain the ultimate tensile force of each tensile test substrate group; obtaining the modified tensile strength of the structural adhesive corresponding to each tensile test substrate group according to the ultimate tensile force, and the calculation formula of the modified tensile strength is: Among them, xzkl (h,j) It is expressed as the modified tensile strength of the structural adhesive corresponding to the jth tensile test substrate group in the hth tensile test environment; jxll (h,j) Represented as xzkl (h,j) Corresponding ultimate tensile force; tfmj (h,j) Represented as xzkl (h,j) Corresponding coating area; hjwd h It is expressed as the ambient temperature of the hth tensile test environment; hjsd h It is represented by the ambient humidity of the hth tensile test environment; f() is represented by a nonlinear analytical function; ccd (h,j) It is expressed as the average surface roughness of the two tensile test substrates in the jth tensile test substrate group in the hth tensile test environment; CCD bz It is represented as standard roughness; χ0, χ1 and χ2 represent tensile strength coefficient, environmental coefficient and roughness coefficient respectively; exp() represents an exponential function with natural constant as base.

7. A tensile test method for a structural adhesive according to claim 1, characterized in that: The tensile test result is the tensile test pass rate of the structural adhesive under N tensile test environments, and the specific acquisition process includes: The tensile test substrate group whose corrected tensile strength is less than the set minimum standard tensile strength is recorded as a tensile test unqualified substrate group; otherwise, the tensile test substrate group is recorded as a tensile test qualified substrate group; obtain the proportion of the tensile test qualified substrate group in each tensile test environment, and record the proportion as the tensile test pass rate.

8. A tensile testing system for structural adhesives, characterized in that: include: A collection unit, used for collecting a plurality of tensile test substrate plates and N tensile test environments of the structural adhesive; A tensile test substrate plate screening unit is used to perform defect detection and roughness detection on the tensile test substrate plate, screen out qualified tensile test substrate plates, and construct a substrate data set; The roughness detection includes: The structural adhesive coating surface of each tensile test substrate plate is divided into M sub-areas, and the arithmetic mean deviation of the contour of each sub-area is detected; according to the arithmetic mean deviation of the contour of the M sub-areas, the roughness detection value of the structural adhesive coating surface is obtained, and the calculation formula is: Among them, ztcc i Ra is the roughness test value of the structural adhesive coating surface of the i-th tensile test substrate plate; (i,j) Represented as ztcc i The arithmetic mean deviation of the contour of the corresponding j-th sub-region; Ra bz Expressed as the set standard deviation value; Var i It is represented as the variance of the arithmetic mean deviation of the contours of the M sub-regions; α1 is represented as the first roughness coefficient; α2 is represented as the second roughness coefficient; when the roughness detection value is less than the set roughness standard value, the roughness detection result is qualified; otherwise, the roughness detection result is unqualified; A tensile test substrate group subset acquisition unit is used to acquire N tensile test substrate group subsets based on the substrate data set; a corrected tensile strength acquisition unit is used to place the tensile test substrate groups in the tensile test substrate group subsets into a corresponding tensile test environment to acquire the corrected tensile strength of the structural adhesive in each of the tensile test substrate groups; a tensile test result acquisition unit is used to acquire the tensile test result of the structural adhesive based on each of the corrected tensile strengths.

9. A tensile testing system for structural adhesives according to claim 8, characterized in that: The process of obtaining the qualified tensile test substrate plate includes: obtaining a surface image of the tensile test substrate plate, the surface image including a first surface image of the structural adhesive coating surface and a second surface image of the universal tensile machine contact surface; Performing defect detection on the first surface image and the second surface image to obtain defect detection results; The defect detection result includes whether there are cracks, depressions, grease and corrosion; when the defect detection result is that there are no cracks, no depressions, no grease and no corrosion, the roughness of the structural adhesive coating surface of the tensile test substrate plate is detected; otherwise, the tensile test substrate plate is an unqualified tensile test substrate plate; when the roughness detection result is unqualified, the tensile test substrate plate is an unqualified tensile test substrate plate; otherwise, the tensile test substrate plate is a qualified tensile test substrate plate, and the surface roughness of the structural adhesive coating surface of the qualified tensile test substrate plate is obtained.

10. A tensile testing system for structural adhesives according to claim 8, characterized in that: The tensile test environment includes: N tensile test environments having different humidity and temperature.

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