CN114354446A - Selection and evaluation method of window sealant for rail vehicle - Google Patents

Abstract

The invention provides a type selection evaluation method for a window sealant of a rail vehicle, which comprises the following steps: initially selecting the type of the adhesive, selecting the low-modulus adhesive that meets the performance index; Different types of samples were coated with multiple strips of adhesive strips, and then passed through the test environment of room temperature curing, soaking in water, high temperature, high temperature and high humidity, and low temperature; artificially accelerated aging performance tests were carried out on the initially selected adhesives, and artificially accelerated aging performance The test includes at least one of ultraviolet aging test, high temperature fatigue vibration test, simulated acid rain soaking test, high and low temperature humidity and heat alternating aging test; compare the performance differences of each adhesive, and select the type of adhesive with the best and most stable evaluation performance as the rail vehicle Window sealant. The invention solves the problem that the adhesive type selection method in the prior art cannot select a reliable sealant suitable for rail vehicle windows.

Description

Selection and evaluation method of window sealant for rail vehicle

technical field

The invention relates to the technical field of rail vehicles, in particular to a method for evaluating the selection and evaluation of sealants for windows of rail vehicles.

Background technique

Window sealants for rail transit vehicles are subject to the combined effects of many external factors such as temperature, humidity, sunlight, and various stresses during service, and aging phenomena such as discoloration, cracking, and edge cracking will occur, mechanical properties will decline, and service life will be reduced. The shortening not only affects the appearance of the vehicle, but also brings certain hidden dangers to the operation of the vehicle, and also poses a problem for the maintenance and after-sales service of the vehicle.

The conventional adhesive selection process only refers to the performance parameters in the adhesive product specification, and only judges the performance of the adhesive according to the standard test method. After the adhesive selected in this way is applied to the vehicle, faults such as sealant cracking and water leakage will still occur during the actual vehicle operation. The aging and destruction of adhesives is affected by a variety of factors. For example, in the high and low temperature cyclic alternating test, due to the different thermal expansion coefficients of the adhesive and the material to be adhered, after many alternating cycles of cold and heat, the bonding interface is prone to cracking, which leads to bonding failure; in the acid rain immersion test In the vibration fatigue test, the periodic stress will lead to the gradual development of small defects in the adhesive, and after a certain period of time, interface damage will occur; In the UV aging test, continuous high-intensity UV irradiation will break the macromolecular chains on the surface of the adhesive, which will lead to cracks on the surface, and the cracks will continue to deepen, gradually causing bonding failure.

It can be seen that the existing method of judging the performance of the adhesive only according to the standard test method cannot select a reliable sealant suitable for the use of rail vehicle windows.

SUMMARY OF THE INVENTION

The main purpose of the present invention is to provide a type selection evaluation method for rail vehicle window sealant, so as to solve the problem that the adhesive type selection method in the prior art cannot select a reliable sealant suitable for rail vehicle windows.

In order to achieve the above purpose, the present invention provides a method for selecting and evaluating types of sealants for rail vehicle windows, which includes: preselecting the type of adhesives, selecting low-modulus adhesives that meet performance indicators for the adhesives; In the test, the adhesive is coated with multiple strips on different types of samples, and then cured at room temperature, soaked in water, high temperature of 60-100 °C, 50-90 °C, high temperature and high humidity higher than 90% relative humidity, In the low temperature test environment of -60 to -20°C, after each test environment, the adhesive strip is peeled off, and the total cohesive failure ratio of each adhesive strip in each test environment is more than 95%, which is qualified; Carry out artificial accelerated aging performance test. The artificial accelerated aging performance test includes at least one of ultraviolet aging test, high temperature fatigue vibration test, simulated acid rain immersion test, high and low temperature humidity and heat alternating aging test, and test and calculate the tensile strength of the adhesive after each test. Tensile shear strength retention rate; compare the performance differences of each adhesive, and select the type of adhesive with the best and most stable performance as the rail vehicle window sealant.

Further, in the primary selection of the adhesive type, according to the performance test report of the adhesive, select the tensile shear strength of 1.5～4.5Mpa, the elongation at break of 200%～450%, and the single side at 23℃ and 50% relative humidity. Adhesive with curing depth ≥12mm/7d, surface dry time ≥10min, glass transition temperature ≤-60℃.

Further, the adhesive includes at least one of polyurethane glue, modified silane glue, and organic silica gel.

Further, when testing the adhesive properties of the initially selected adhesives, apply three strips of each of the initially selected adhesives on the four sample plates of glass, aluminum alloy, stainless steel and glass fiber reinforced plastic with a width of 9-11mm and a height of more than 5mm. , the length of the strip is greater than 300mm, and then cured at room temperature for 7 days, soaked in water for 7 days, high temperature of 60-100 ℃ for 1 day, 50-90 ℃ and higher than 90% relative humidity for 7 days at high temperature and high humidity, -60 To a low temperature of -20°C for 1 day in the test environment.

Further, the test environment was cured in an environment of 23°C and 50% relative humidity for 7 days; soaked in water for 7 days at 23°C, and then taken out to adjust at room temperature for 2h; placed at 80°C for 1 day and immediately detected, high temperature After taking it out, adjust for 2 hours; place it in an environment of 70 °C and 95% relative humidity for 7 days and then take it out for 2 hours at room temperature; place it at -40 °C for 1 day in a five-step continuous test environment, and peel off the adhesive strip after each test environment.

Further, in the artificial accelerated aging performance test of each of the primary adhesives, three samples of aluminum alloy-glass, stainless steel-glass, and glass fiber reinforced plastics connected by the adhesive were prepared for tensile shearing samples, and then subjected to ultraviolet aging. Test, high temperature fatigue vibration test, simulated acid rain immersion test, high and low temperature humidity and heat alternating aging test.

Further, in the ultraviolet aging test, three kinds of samples of aluminum alloy-glass, stainless steel-glass, and glass fiber reinforced plastics connected by adhesive were used to prepare tensile shear samples, and a 20% strain was applied to the samples using tooling, and 8h drying, UV wavelength 340nm, irradiance 0.76±0.02W/m ² ×nm, blackboard temperature 60±3℃, 4h condensation, blackboard temperature 50±3℃ cycle, each sample was tested for a cycle of Three tests of 1000h, 1500h, and 2000h, test and calculate the retention rate of tensile shear strength after each test cycle.

Further, in the high-temperature fatigue vibration test, three kinds of samples of aluminum alloy-glass, stainless steel-glass, and glass fiber reinforced plastics connected by adhesive were used to prepare tensile shear samples, and the thickness of the adhesive layer was 4-6mm. The fatigue aging test of the adhesive material is carried out at ℃. The sample amplitude is 1.0mm, the frequency is 30Hz, and the cycle is at least 1 million times. The tensile shear strength retention rate before and after aging is tested and calculated.

Further, in the simulated acid rain soaking test, three kinds of samples of aluminum alloy-glass, stainless steel-glass, and glass fiber reinforced plastics connected by adhesives were prepared for tensile shearing samples, and 20% strain was applied to the samples using tooling, Each sample was soaked in a simulated acid rain solution with pH=2.0 at 40°C for 480h, 960h, and 1440h, and the samples were taken out at each time point for tensile shear strength, and the tensile shear strength was tested and calculated. retention rate.

Further, in the high and low temperature humidity and heat alternating aging test, three kinds of samples of aluminum alloy-glass, stainless steel-glass, and glass fiber reinforced plastics connected by adhesive were used to prepare tensile shear samples, and were subjected to 80°C, 95% relative Placed under humidity for 4h, cooled to -40°C within 2h, placed at -40°C for 4h, heated to 80°C within 2h, 95% relative humidity cycle, each sample was tested for 480h, 720h, 960h, Four tests of 1440h were tested and the retention of tensile shear strength was measured and calculated after each test cycle.

Further, when selecting the type of adhesive with the best evaluation performance and the most stable as the rail vehicle window sealant, the adhesive with the retention rate of tensile shear strength greater than 55% is selected as the best and most stable adhesive.

By applying the technical scheme of the present invention, the adhesives used in the window sealing of rail vehicles are strictly screened through three stages. In the artificial accelerated aging performance test, ultraviolet aging test, high temperature fatigue vibration test, simulated acid rain immersion test, high and low temperature humidity and heat alternating aging test can be carried out, so that the performance of the adhesive can be fully verified and evaluated, and real substrates are selected for artificial accelerated aging performance test. And a certain strain is applied to the sample to simulate the deformation of the vehicle under load during the actual operation of the vehicle, which is closer to the load condition in the real vehicle operation. The application of the qualified adhesive to the window sealing of rail vehicles through the above evaluation methods can prevent the cracking of the sealant and the phenomenon of rain leakage during the operation of the vehicle, ensure the sealing of the windows of the rail vehicle, improve the passenger comfort, and reduce the operation of the vehicle. Failure to ensure the environmental requirements of the window seal and the normal operation and maintenance cycle. At the same time, it makes up for the existing gaps in the aging method and related performance evaluation of bonded joints in complex service environments, and has the advantages of more complete performance evaluation and saving aging test time.

Description of drawings

The accompanying drawings forming a part of the present application are used to provide further understanding of the present invention, and the exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the attached image:

Fig. 1 shows the flow chart of the method for selecting and evaluating type of sealant for rail vehicle window of the present invention;

Fig. 2 shows the flow chart of the bonding performance test of the method for selecting and evaluating the sealant for rail vehicle window in Fig. 1;

Fig. 3 shows a schematic diagram of applying 20% strain to the tensile shear specimen of the method for evaluating the selection and evaluation of sealant for rail vehicle windows in Fig. 1;

FIG. 4 shows a schematic diagram of a cycle in the high and low temperature humidity and heat alternating aging test of the method for evaluating the selection and evaluation of sealant for rail vehicle windows in FIG. 1 .

Detailed ways

It should be noted that the embodiments in the present application and the features of the embodiments may be combined with each other in the case of no conflict. The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

In the present invention, unless otherwise stated, the directional words used such as "upper, lower, top, bottom" are usually for the directions shown in the drawings, or for the components themselves in vertical, In terms of vertical or gravitational direction; similarly, for the convenience of understanding and description, "inner and outer" refers to the inner and outer relative to the contour of each component itself, but the above-mentioned orientation words are not used to limit the present invention.

In order to solve the problem that the adhesive type selection method in the prior art cannot select a reliable sealant suitable for rail vehicle windows, the present invention provides a type selection evaluation method for rail vehicle window sealants.

As shown in Figure 1, a method for evaluating the selection and evaluation of sealants for rail vehicle windows includes: primary selection of adhesive types, and selection of low-modulus adhesives that meet performance indicators; The adhesive is coated with multiple strips on different types of samples, and then cured at room temperature, soaked in water, high temperature of 60-100 ° C, 50-90 ° C, high temperature and high humidity higher than 90% relative humidity, -60 to In the low temperature test environment of -20°C, after the end of each test environment, the adhesive strip is peeled off, and the total cohesive failure ratio of each adhesive strip in each test environment is more than 95%, which is qualified; artificial acceleration is performed on the primary adhesives. Aging performance test, artificial accelerated aging performance test includes at least one of ultraviolet aging test, high temperature fatigue vibration test, simulated acid rain immersion test, high and low temperature humidity and heat alternating aging test, test and calculate the tensile shear of the adhesive after each test Strength retention rate; compare the performance differences of various adhesives, and select the type of adhesive with the best and most stable evaluation performance as the rail vehicle window sealant.

In this embodiment, the adhesives used in the window sealing of rail vehicles are strictly screened in three stages. Specifically, it is divided into three stages: primary selection of adhesives, adhesion performance test and artificial accelerated aging performance test. In the performance test, ultraviolet aging test, high temperature fatigue vibration test, simulated acid rain immersion test, high and low temperature humidity and heat alternating aging test are carried out, so that the performance of the adhesive can be fully verified and evaluated. A certain strain is applied to simulate the deformation of the vehicle under load during the actual operation of the vehicle, which is closer to the load condition in the actual vehicle operation. The application of the qualified adhesive to the window sealing of rail vehicles through the above evaluation methods can prevent the cracking of the sealant and the phenomenon of rain leakage during the operation of the vehicle, ensure the sealing of the windows of the rail vehicle, improve the passenger comfort, and reduce the operation of the vehicle. Failure to ensure the environmental requirements of the window seal and the normal operation and maintenance cycle. At the same time, it makes up for the existing gaps in the aging method and related performance evaluation of bonded joints in complex service environments, and has the advantages of more complete performance evaluation and saving aging test time.

In this embodiment, when the type of adhesive is initially selected, according to the performance test report of the adhesive, the tensile shear strength is 1.5-4.5Mpa, the elongation at break is 200%-450%, and the single-sided curing depth (23°C, 50% relative humidity environment) ≥ 12mm/7d (mm/day), surface dry time ≥ 10min, glass transition temperature (median) ≤ -60 ℃ adhesive. And the adhesive component includes at least one of polyurethane glue, modified silane glue, and organic silica gel, and the type is preferably low-modulus glue such as polysulfide glue, polyurethane glue, and modified silane glue. Adhesive models that meet the above performance indicators can be used as the initially selected adhesives for follow-up tests.

In this embodiment, in order to verify the adhesion effect between the adhesive and the actual bonding substrate, and to simulate the extreme environmental conditions of rail vehicle operation, the adhesive performance test is carried out on each of the initially selected adhesives. During the test, each of the initially selected adhesives was coated with three strips of 9-11mm in width, preferably 10mm in width, 5mm in height and 300mm in length on each of the four samples of glass, aluminum alloy, stainless steel and glass fiber reinforced plastic, and then After curing at room temperature for 7 days, soaking in water for 7 days, high temperature of 60-100°C for 1 day, high temperature and humidity of 50-90°C and higher than 90% relative humidity for 7 days, and low temperature of -60 to -20°C for 1 day test environment. The above parameters such as width and height are used to facilitate the use of needle-nose pliers to cut and roll off in subsequent operations, and the rubber strip is not easy to break. Each test condition required a stripping length of 50mm, for a total of 300mm lengths for the 6 test stages. The specific parameters of the above temperature and humidity can be selected according to needs.

Specifically, as shown in FIG. 2 , the test environment of this embodiment is followed by curing in an environment of 23°C and 50% relative humidity for 7 days; soaking in water for 7 days at an ambient temperature of 23°C and then taking out room temperature for 2h adjustment; Put it in the environment of 80℃ for 1 day and test immediately, take out the high temperature of 80℃ and adjust for 2h; put it in the environment of 70℃ and 95% relative humidity for 7 days and then take out the room temperature and adjust it for 2h; put it at the low temperature of -40℃ for 1 day in five-step continuous test environment , the strips are peeled off after each test environment. Among them, the strips need to be stripped for 1 day at 80 °C for immediate detection and 2 hours after taking out at 80 °C for a total of 6 strippings. Five of the above five stages correspond to the adhesion between the adhesive and the bonding substrate under the five environments of room temperature curing, high humidity (water soaking), high temperature, high temperature and high humidity, and low temperature conditions. After each test environment is finished, the adhesive strip is peeled off, and the total adhesion failure ratio of the three parallel samples after each test environment is greater than 95%, which is an adhesive with qualified adhesion, which is further screened out. adhesive. The above process is carried out using a high and low temperature damp heat test chamber.

The artificial accelerated aging performance test in this embodiment includes four tests: ultraviolet aging test, high temperature fatigue vibration test, simulated acid rain soaking test, and high and low temperature humidity and heat alternating aging test, that is, the above four tests are performed on the adhesive to ensure that the test results are comprehensive and reliable. . Of course, the actual test can also be selectively carried out according to actual needs. In the artificial accelerated aging performance test of the primary selected adhesives, tensile shear samples were prepared from three kinds of samples of aluminum alloy-glass, stainless steel-glass and glass fiber reinforced plastics connected by adhesives, and then subjected to ultraviolet aging test, High temperature fatigue vibration test, simulated acid rain immersion test, high and low temperature humidity and heat alternating aging test.

Specifically, during the ultraviolet aging test, three kinds of samples of aluminum alloy-glass, stainless steel-glass, and glass fiber reinforced plastics connected by adhesive were prepared to prepare tensile shear samples, and a 20% strain was applied to the samples using tooling. As shown in Figure 3, and were respectively dried for 8h, UV wavelength 340nm, irradiance 0.76±0.02W/m ² ×nm, blackboard temperature 60±3℃, 4h condensation, blackboard temperature 50±3℃, each cycle. The samples were tested three times with test cycles of 1000h, 1500h, and 2000h, that is, the three samples were all subjected to the test process of this test cycle, and the tensile shear strength retention rate was measured and calculated after each test cycle. This process is carried out using a UV lamp accelerated aging test chamber.

In the high-temperature fatigue vibration test, three kinds of samples of aluminum alloy-glass, stainless steel-glass, and glass fiber reinforced plastics connected by adhesive are used to prepare tensile shear samples, and the thickness of the adhesive layer is 4-6mm, preferably 5mm, at 70 The fatigue aging test of the adhesive material is carried out at ℃. The sample amplitude is 1.0mm, the frequency is 30Hz, and the cycle is at least 1 million times. The tensile shear strength retention rate before and after aging is tested and calculated. This process is carried out using a fatigue testing machine.

In the simulated acid rain immersion test, tensile shear specimens were prepared from three specimens of aluminum alloy-glass, stainless steel-glass, and glass fiber reinforced plastics connected by adhesives, and a 20% strain was applied to the specimens using a tooling. The samples were soaked in simulated acid rain solution with pH=2.0 at 40°C for 480h, 960h, and 1440h. The samples were taken out at each time point for tensile shear strength, and the tensile shear strength retention rate was measured and calculated. This process is carried out using a high and low temperature damp heat test chamber.

During the high and low temperature humidity and heat alternating aging test, three kinds of samples of aluminum alloy-glass, stainless steel-glass, and glass fiber reinforced plastics connected by adhesive were prepared for tensile shearing samples, and they were placed at 80°C and 95% relative humidity. 4h, cooling to -40°C within 2h, placing at -40°C for 4h, heating to 80°C within 2h, 95% relative humidity cycle, as shown in Figure 4, each sample was tested for 480h, 720h , 960h, 1440h four tests, that is, the three samples are all subjected to the test process of this test cycle, and the tensile shear strength retention rate is measured and calculated after each test cycle. This process is carried out using a high and low temperature damp heat test chamber.

It should be noted that the above-mentioned sample connected by adhesive means that the two materials of the sample are connected by adhesive to form a whole. For example, aluminum alloy-glass means that aluminum alloy and glass are bonded by adhesive. wait together.

In the above-mentioned ultraviolet aging test, simulated acid rain soaking test, and alternating high and low temperature humidity and heat aging test, each test is carried out for several times with different test cycles. Taking the UV aging test as an example, a total of nine tests are required for the three samples. In order to reduce the number of tests, the test environment based on the three samples is the same. In the actual test, the three samples can be tested in the same cycle at the same time. For example, in the ultraviolet aging test, the three samples can be tested at the same time. The test cycle is 1000h in a specific environment, so the three samples only need to be tested three times in total for three cycles, which greatly reduces the number of tests and improves the test efficiency.

In this embodiment, in order to make the material of the sample consistent with the material that the adhesive actually contacts in the vehicle window sealant, three samples of aluminum alloy-glass, stainless steel-glass, and glass fiber reinforced plastics formed by adhesive bonding are used. Of course, the specific materials of the above three samples can also be changed according to actual needs.

After the above test is completed, the performance difference of each adhesive is compared, and the window sealant for rail vehicles is selected. When selecting, the type of adhesive with the best evaluation performance and the most stable is selected as the rail vehicle window sealant, and more specifically, the adhesive with the retention rate of tensile shear strength greater than 55% is selected as the best and most stable adhesive.

It should be noted that, the specific parameters in the above embodiments can be adjusted correspondingly as required, and the plurality of parameters in the above embodiments refers to at least two.

From the above description, it can be seen that the above-mentioned embodiments of the present invention achieve the following technical effects:

1. Solve the problem that the adhesive type selection method in the prior art cannot select a reliable sealant suitable for the use of rail vehicle windows;

2. Fully verify and evaluate the performance of the adhesive, select the real substrate for artificial accelerated aging performance test and apply a certain strain to the sample to simulate the deformation of the vehicle under load during the actual operation of the vehicle, which is closer to the load in the real vehicle operation working condition;

3. The application of the qualified adhesive to the window seal of the rail vehicle through the evaluation method can prevent the cracking of the sealant and the rain leakage during the operation of the vehicle, ensure the sealing of the window of the rail vehicle, improve the passenger comfort, and reduce the number of vehicles. Operation failure ensures the window sealing environment requirements and the normal operation and maintenance cycle;

4. It makes up for the existing gaps in the aging method and related performance evaluation of adhesive joints in complex service environments, and has the advantages of more complete performance evaluation and saving aging test time.

Obviously, the above-described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

It should be noted that the terminology used herein is for the purpose of describing specific embodiments only, and is not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly dictates otherwise, the singular is intended to include the plural as well, furthermore, it is to be understood that when the terms "comprising" and/or "including" are used in this specification, it indicates that There are features, steps, acts, devices, components, and/or combinations thereof.

It should be noted that the terms "first", "second", etc. in the description and claims of the present application and the above drawings are used to distinguish similar objects, and are not necessarily used to describe a specific sequence or sequence. It is to be understood that data so used may be interchanged under appropriate circumstances so that the embodiments of the application described herein can be practiced in sequences other than those illustrated or described herein.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (11)

1. A rail vehicle window sealant selection evaluation method is characterized by comprising the following steps:

primarily selecting the type of an adhesive, wherein the adhesive selects a low-modulus adhesive meeting performance indexes;

testing the bonding performance of each initially selected adhesive, coating a plurality of adhesive strips on different types of sample plates respectively by the adhesive, sequentially carrying out normal-temperature curing, water soaking, high temperature of 60-100 ℃, high temperature and high humidity of 50-90 ℃ and relative humidity higher than 90%, and low-temperature testing environments of-60 ℃ to-20 ℃, stripping the adhesive strips after each testing environment is finished, and determining that the total cohesive failure proportion of each adhesive strip in each testing environment is greater than 95% to be qualified;

carrying out artificial accelerated aging performance test on each preliminarily selected adhesive, wherein the artificial accelerated aging performance test comprises at least one of an ultraviolet aging test, a high-temperature fatigue vibration test, a simulated acid rain soaking test and a high-low temperature damp-heat alternating aging test, and the tensile shear strength retention rate of the adhesive is tested and calculated after each test;

and comparing the performance difference of the adhesives, and selecting the adhesive type with the best and most stable evaluation performance as the rail vehicle window sealant.

2. The rail vehicle window sealant type selection evaluation method as claimed in claim 1, wherein when the type of the adhesive is initially selected, according to the performance detection report of the adhesive, the adhesive with the tensile shear strength of 1.5-4.5 Mpa, the elongation at break of 200% -450%, the single-side curing depth of more than or equal to 12mm/7d at 23 ℃ and 50% relative humidity, the surface drying time of more than or equal to 10min and the glass transition temperature of less than or equal to-60 ℃ is selected.

3. The rail vehicle window sealant selection evaluation method as claimed in claim 1, wherein the adhesive comprises at least one of a polyurethane adhesive, a modified silane adhesive, and a silicone adhesive.

4. The rail vehicle window sealant type selection evaluation method as claimed in claim 1, wherein when the bonding performance of each of the preliminarily selected adhesives is tested, each of the preliminarily selected adhesives is coated with three adhesive tapes with the width of 9-11mm, the height of more than 5mm and the length of more than 300mm on four sample plates of glass, aluminum alloy, stainless steel and glass fiber reinforced plastic, and then the adhesive tapes are sequentially subjected to the test environments of normal temperature curing for 7 days, water soaking for 7 days, high temperature of 60-100 ℃ for 1 day, high temperature and high humidity of 50-90 ℃ and higher than 90% relative humidity for 7 days, and low temperature of-60 to-20 ℃ for 1 day.

5. The rail vehicle window sealant type selection evaluation method as claimed in claim 4, wherein the test environment is sequentially cured for 7 days at 23 ℃ and 50% relative humidity; soaking in water at 23 deg.C for 7 days, and adjusting for 2 hr; standing at 80 deg.C for 1 day, immediately detecting, taking out at high temperature, and adjusting for 2 hr; standing at 70 deg.C and 95% relative humidity for 7 days, and adjusting room temperature for 2 h; and (3) placing the test piece at the low temperature of minus 40 ℃ for 1 day in five continuous test environments, and stripping the adhesive tape after each test environment is finished.

6. The rail vehicle window sealant type selection evaluation method as claimed in claim 1, wherein when each preliminarily selected adhesive is subjected to an artificial accelerated aging performance test, three samples of aluminum alloy-glass, stainless steel-glass and glass fiber reinforced plastic-glass connected by the adhesive are prepared into tensile shear samples, and then the ultraviolet aging test, the high temperature fatigue vibration test, the simulated acid rain soaking test and the high and low temperature damp and hot alternation aging test are performed.

7. The rail vehicle window seal of claim 1The glue type selection evaluation method is characterized in that when the ultraviolet aging test is carried out, three samples of aluminum alloy-glass, stainless steel-glass and glass fiber reinforced plastic-glass connected by the adhesive are prepared into tensile shearing samples, a tool is used for applying 20% strain to the samples, and the samples are respectively dried for 8 hours, wherein the ultraviolet wavelength is 340nm, and the irradiance is 0.76 +/-0.02W/m²And (3) multiplying the test sample by nm, wherein the blackboard temperature is 60 +/-3 ℃, the blackboard is condensed for 4 hours, the blackboard temperature is 50 +/-3 ℃, three tests with the test periods of 1000 hours, 1500 hours and 2000 hours are carried out on each sample, and the tensile shear strength retention rate is tested and calculated after each test period.

8. The rail vehicle window sealant type selection evaluation method as claimed in claim 1, wherein in the high temperature fatigue vibration test, three samples of aluminum alloy-glass, stainless steel-glass and glass fiber reinforced plastic-glass connected by the adhesive are prepared into tensile shear samples, the thickness of the adhesive layer is 4-6mm, the fatigue aging test of the adhesive material is carried out at 70 ℃, the amplitude of the sample is 1.0mm, the frequency is 30Hz, the cycle is carried out for at least 100 ten thousand times, and the retention rate of the tensile shear strength before and after aging is tested and calculated.

9. The rail vehicle window sealant type selection evaluation method according to claim 1, wherein in the simulated acid rain soaking test, three samples of aluminum alloy-glass, stainless steel-glass and glass fiber reinforced plastic-glass connected by the adhesive are prepared into tensile shear samples, a tool is used for applying a strain of 20% to the samples, each sample is soaked in a simulated acid rain solution with a pH value of 2.0 at 40 ℃ for 480h, 960h and 1440h, the samples are taken out in sequence at each time point for tensile shear strength, and the tensile shear strength retention rate is tested and calculated.

10. The method for selectively evaluating the rail vehicle window sealant according to claim 1, wherein in the high and low temperature humid heat alternating aging test, three samples of aluminum alloy-glass, stainless steel-glass and glass fiber reinforced plastic-glass connected by the adhesive are prepared into tensile shear samples, and are placed for 4h at 80 ℃ and 95% relative humidity, cooled to-40 ℃ within 2h, placed for 4h at-40 ℃ and heated to 80 ℃ and 95% relative humidity within 2h, each sample is subjected to four tests with test periods of 480h, 720h, 960h and 1440h, and the tensile shear strength retention rate is tested and calculated after each test period.

11. The rail vehicle window sealant type selection evaluation method as claimed in claim 1, wherein when an adhesive type with the best and most stable evaluation performance is selected as the rail vehicle window sealant, the adhesive with the tensile shear strength retention rate of more than 55% is selected as the best and most stable adhesive.

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