Method and device for testing performance retention rate of carbon fiber after friction

Abstract

The invention provides a method and a device for testing the performance retention rate of carbon fibers after friction. The test method comprises the following steps: carrying out friction test on to-be-tested carbon fibers; and determining the performance retention rate of the to-be-tested carbon fiber after friction test according to the ratio of the mechanical properties of the to-be-tested carbon fiber after friction test to the mechanical properties of the to-be-tested carbon fiber before friction test. According to the method for testing the performance retention rate of the carbon fiber after friction, the friction test is performed by simulating the friction condition of the carbon fiber in the actual field processing process, and the performance retention rate of the carbon fiber after friction can be quantitatively and accurately represented according to the ratio of the mechanical properties of the carbon fiber to be tested before and after the friction test; a reliable basis is provided for the structural design of the carbon fiber composite material, and the wide application of the carbon fiber is promoted. The testing method is simple, efficient and easy to operate.

Description

Technical Field

[0001] The present disclosure relates to the field of carbon fiber performance testing, and particularly to a testing method and device for the performance retention rate of carbon fiber after friction. Background Art

[0002] Carbon fiber is a new fiber material with high strength and high modulus fibers containing more than 90% carbon. Carbon fiber has advantages such as high specific strength, high specific modulus, light weight, fatigue resistance, and designability. Carbon fiber has the inherent intrinsic characteristics of carbon materials and at the same time has the soft processability of textile fibers. It is a new generation of reinforcing fibers and is widely used in fields such as aerospace, new energy, and sports goods. Currently, the performance evaluation items provided by domestic and foreign carbon fiber manufacturers are limited, including fiber tensile strength, elastic modulus, elongation at break, ash content, carbon content, fuzzing amount, etc. There is less evaluation of the performance retention rate of carbon fiber after processing. For example, during the weaving process, the carbon fiber bundles are frequently intertwined and rubbed against each other and rubbed against the rollers multiple times, which will damage the tensile performance of the carbon fiber and reduce the performance of the carbon fiber after processing.

[0003] The performance retention rate of carbon fiber after friction affects its performance utilization rate in carbon fiber composites. The performance utilization rate of carbon fiber restricts the safety threshold of the structural design of carbon fiber composites, and the selection of the structural design of carbon fiber composites affects the wide application of carbon fiber in various fields. Therefore, how to accurately quantify and evaluate the performance of carbon fiber after friction becomes increasingly important. Summary of the Invention

[0004] To solve the problems existing in the related art, the present disclosure provides a testing method and device for the performance retention rate of carbon fiber after friction.

[0005] According to the first aspect of the embodiments of the present disclosure, a testing method for the performance retention rate of carbon fiber after friction is provided. The testing method includes:

[0006] Performing a friction test on the carbon fiber to be tested;

[0007] Determining the performance retention rate of the carbon fiber to be tested after friction according to the ratio of the mechanical properties of the carbon fiber to be tested after the friction test to the mechanical properties of the carbon fiber to be tested before the friction test.

[0008] In some embodiments of the present disclosure, the mechanical properties include tensile strength, elastic modulus, and elongation at break.

[0009] In some embodiments of the present disclosure, the determining the performance retention rate of the carbon fiber to be tested after friction according to the ratio of the mechanical properties of the carbon fiber to be tested after the friction test to the mechanical properties of the carbon fiber to be tested before the friction test includes:

[0010] Determine the performance retention rate of the carbon fiber to be tested after friction according to the ratio of the tensile strength of the carbon fiber to be tested after the friction test to the tensile strength of the carbon fiber to be tested before the friction test; and / or,

[0011] The determining the performance retention rate of the carbon fiber to be tested after friction according to the ratio of the mechanical properties of the carbon fiber to be tested after the friction test to the mechanical properties of the carbon fiber to be tested before the friction test includes:

[0012] Determine the performance retention rate of the carbon fiber to be tested after friction according to the ratio of the elastic modulus of the carbon fiber to be tested after the friction test to the elastic modulus of the carbon fiber to be tested before the friction test; and / or,

[0013] The determining the performance retention rate of the carbon fiber to be tested after friction according to the ratio of the mechanical properties of the carbon fiber to be tested after the friction test to the mechanical properties of the carbon fiber to be tested before the friction test includes:

[0014] Determine the performance retention rate of the carbon fiber to be tested after friction according to the ratio of the elongation at break of the carbon fiber to be tested after the friction test to the elongation at break of the carbon fiber to be tested before the friction test.

[0015] In some embodiments of the present disclosure, the performing the friction test on the carbon fiber to be tested includes:

[0016] Traction the carbon fiber to be tested under preset conditions and pass it through a preset friction roller set for the friction test.

[0017] In some embodiments of the present disclosure, the preset conditions include: the tension is 50-100 N, and the traction speed is 0-10 m / min.

[0018] In some embodiments of the present disclosure, the preset friction roller set includes 6-20 friction rollers; when the carbon fiber to be tested passes through each friction roller, the included angle between the carbon fiber to be tested on both sides of the friction roller is 30-150°.

[0019] In some embodiments of the present disclosure, the test method further includes:

[0020] Obtain the amount of fuzz of the carbon fiber to be tested after the friction test.

[0021] According to the second aspect of the embodiments of the present disclosure, there is provided a test device for the performance retention rate of carbon fiber after friction, and the test device includes:

[0022] An unwinding mechanism for unwinding the carbon fiber to be tested;

[0023] A winding mechanism for winding the carbon fiber to be tested;

[0024] A control system for controlling the tension and traction speed of the carbon fiber to be tested;

[0025] A friction system is arranged between the unwinding mechanism and the winding mechanism, and the friction system is used for performing friction tests on the carbon fiber to be tested.

[0026] In some embodiments of the present disclosure, the friction system includes a preset friction roller group, and the preset friction roller group includes 6 to 20 friction rollers; when the carbon fiber to be tested passes through each friction roller, the included angle between the carbon fiber to be tested on both sides of the friction roller is 30 to 150°.

[0027] In some embodiments of the present disclosure, the testing device further includes a fluff collecting mechanism, which is arranged between the friction system and the winding mechanism, and the fluff collecting mechanism is used for collecting the fluff of the carbon fiber to be tested after the friction test.

[0028] The beneficial effects of the present disclosure include but are not limited to: the testing method for the performance retention rate of carbon fiber after friction provided by the present disclosure, by simulating the friction situation of carbon fiber in the actual on-site processing process, performing friction tests, and according to the ratio of the mechanical properties of the carbon fiber to be tested before and after the friction test, the performance retention rate of the carbon fiber to be tested can be quantitatively and accurately characterized, providing a reliable basis for the structural design of carbon fiber composites and promoting the wide application of carbon fiber. This testing method is simple, efficient, and easy to operate.

[0029] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings incorporated into the specification and constituting a part of the specification illustrate the embodiments of the present disclosure and are used together with the description to explain the principles of the embodiments of the present disclosure. In these drawings, like reference numerals are used to represent like elements. The drawings in the following description are some embodiments of the present disclosure, not all embodiments. For those skilled in the art, other drawings can be obtained based on these drawings without creative efforts.

[0031] Figure 1 It is a schematic flowchart of the testing method for the performance retention rate of carbon fiber after friction according to an exemplary embodiment of the present disclosure;

[0032] Figure 2 It is a schematic diagram of the testing device for the performance retention rate of carbon fiber after friction according to an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] To make the objectives, technical solutions, and advantages of the present disclosure clearer, the technical solutions of the present disclosure will be clearly and completely described below in conjunction with the embodiments of the present disclosure. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present disclosure. It should be noted that, without conflict, the embodiments in the present disclosure and the features in the embodiments may be arbitrarily combined with each other.

[0034] After carbon fiber is processed, such as during the weaving process where there is frequent interweaving and friction between carbon fiber bundles and multiple frictions with rollers, the tensile properties of the carbon fiber will be damaged, reducing the performance of the carbon fiber after processing. The performance retention rate of the carbon fiber after friction affects its performance utilization rate in carbon fiber composites. The performance utilization rate of the carbon fiber restricts the safety threshold of the structural design of carbon fiber composites, and the selection of the structural design of carbon fiber composites affects the wide application of carbon fiber in various fields. Therefore, how to accurately quantify and evaluate the performance of carbon fiber after friction becomes increasingly important.

[0035] Based on this, the exemplary embodiments of the present disclosure provide a test method for the performance retention rate of carbon fiber after friction, as Figure 1 shown. This test method includes:

[0036] S100. Conduct a friction test on the carbon fiber to be tested.

[0037] The friction test on the carbon fiber to be tested can be to simulate the actual processing conditions of the carbon fiber on-site. For example, when a certain type or batch of carbon fiber is woven, if it is necessary to measure the performance retention rate of the carbon fiber of this type or batch after friction during the weaving process, the carbon fiber of this type or batch can be used as the carbon fiber to be tested, and traction friction can be carried out under the conditions of simulated weaving processing to obtain the performance retention rate of the carbon fiber to be tested after the friction test.

[0038] S200. Determine the performance retention rate of the carbon fiber to be tested after friction according to the ratio of the mechanical properties of the carbon fiber to be tested after the friction test to the mechanical properties of the carbon fiber to be tested before the friction test.

[0039] After the carbon fiber to be tested is subjected to traction friction under the conditions of simulated weaving processing, the friction situation of the carbon fiber during the actual weaving process on-site can be simulated. According to the ratio of the mechanical properties of the carbon fiber to be tested after the friction test to the mechanical properties of the carbon fiber to be tested before the friction test, the performance retention rate of the carbon fiber to be tested after friction can be determined.

[0040] The test method for the performance retention rate of carbon fiber after friction provided by this exemplary embodiment can quantitatively and accurately characterize the performance retention rate of the carbon fiber to be tested after friction by simulating the friction situation during the actual processing of carbon fiber on site, conducting friction tests, and based on the ratio of the mechanical properties of the carbon fiber to be tested before and after the friction test. This provides a reliable basis for the structural design of carbon fiber composites and promotes the wide application of carbon fiber. This test method is simple, efficient, and easy to operate.

[0041] In the exemplary embodiment provided by the present disclosure, performing a friction test on the carbon fiber to be tested includes: pulling the carbon fiber to be tested under preset conditions and passing it through a preset friction roller set for friction testing.

[0042] In this embodiment, the friction test on the carbon fiber to be tested can be a friction test on the carbon fiber to be tested by simulating the actual processing conditions of carbon fiber on site. For example, when weaving and processing a certain type or batch of carbon fiber, if it is necessary to measure the performance retention rate of this type or batch of carbon fiber after friction during the weaving and processing process, then this type or batch of carbon fiber can be taken as the carbon fiber to be tested, the preset conditions can be set as the conditions during the imitation weaving and processing process, pulled under the preset conditions, and passed through a preset friction roller set, where the preset friction roller set is the friction roller set that the carbon fiber passes through during the imitation weaving and processing process, such as the number and angle settings of the guide rollers that the carbon fiber passes through during the imitation weaving and processing process. After pulling the carbon fiber to be tested through the preset friction roller set under the preset conditions, the friction situation during the actual weaving and processing process of carbon fiber on site can be simulated.

[0043] In the exemplary embodiment provided by the present disclosure, the preset conditions include: the tension is 50 - 100 N, and the pulling speed is 0 - 10 m / min.

[0044] In this embodiment, setting the tension during the pulling friction test of the carbon fiber to be tested to 50 - 100 N can avoid problems such as the carbon fiber to be tested being loose due to too small a tension and insufficient frictional contact with the preset friction roller set, and can also prevent damage or breakage of the carbon fiber to be tested during the friction test due to too large a tension, which affects the test result of the performance retention rate of the carbon fiber to be tested after friction. Setting the tension during the pulling friction test of the carbon fiber to be tested to 50 - 100 N can ensure that the stress state of the carbon fiber to be tested during the friction test is close to the stress situation during the actual carbon fiber processing process, making the friction test result more reliable and repeatable. For example, the tension during the pulling friction test of the carbon fiber to be tested can be set to 50 N, 70 N, 90 N, or 100 N. The tension during the pulling friction test of the carbon fiber to be tested can also be any value between the exemplary tensions. For example, the tension during the pulling friction test of the carbon fiber to be tested can also be any value between 60 - 90 N.

[0045] In this embodiment, the traction speed during the friction test of the carbon fiber to be tested is set to 0-10 m / min, which can avoid the problem that the traction speed is too fast and the carbon fiber to be tested is not in sufficient frictional contact with the preset friction roller set. For example, the traction speed during the friction test of the carbon fiber to be tested can be set to 0 m / min (static friction), 3 m / min, 6 m / min or 10 m / min. The traction speed during the friction test of the carbon fiber to be tested can also be any value between the exemplary traction speeds. For example, the traction speed during the friction test of the carbon fiber to be tested can also be any value between 2-8 m / min.

[0046] In the exemplary embodiment provided by the present disclosure, the preset friction roller set includes 6-20 friction rollers; when the carbon fiber to be tested passes through each friction roller, the included angle between the carbon fibers to be tested on both sides of the friction roller is 30-150°.

[0047] In this embodiment, the preset friction roller set through which the carbon fiber to be tested is tractioned during the friction test is set to 6-20 friction rollers, and the wear situation of the actual carbon fiber continuously passing through the guide roller or contact point on site is simulated through multiple frictions (for example, each time passing through a friction roller is a bending friction). Setting the preset friction roller set to 6-20 friction rollers can avoid the insufficient number of friction times of the carbon fiber to be tested caused by too few friction rollers, which cannot reflect the real frictional damage, and can also avoid the over-amplification of frictional damage caused by too many friction rollers, exceeding the on-site actual scenario requirements. For example, the preset friction roller set can be set to 6, 10, 15 or 20 friction rollers. The number of friction rollers in the preset friction roller set can also be any value between the exemplary number of friction rollers. For example, the number of friction rollers in the preset friction roller set can also be any value between 8-15.

[0048] In this embodiment, setting the included angle between the carbon fibers to be tested on both sides of the friction roller to 30-150° can control the shear force and normal force of the friction between the carbon fiber to be tested and the friction roller by adjusting the contact arc between the carbon fiber to be tested and the friction roller, so as to simulate different on-site actual friction situations and ensure that the test results can reflect the performance retention ability of the carbon fiber under complex working conditions. For example, the included angle between the carbon fibers to be tested on both sides of the friction roller can be set to 30°, 60°, 90° or 150°, and the included angle between the carbon fibers to be tested on both sides of the friction roller can also be any value between the exemplary included angles. For example, the included angle between the carbon fibers to be tested on both sides of the friction roller can also be any value between 60-120°.

[0049] In the exemplary embodiment provided by the present disclosure, the mechanical properties include tensile strength, elastic modulus and elongation at break.

[0050] After subjecting the carbon fiber to be tested to a friction test, collect 15 to 30 meters of the carbon fiber to be tested after the friction test, and conduct a mechanical property test on the mechanical properties of 15 to 30 meters of the carbon fiber to be tested without the friction test (before the friction test). Among them, the mechanical properties to be tested can be any item that can evaluate the mechanical properties of the carbon fiber, such as tensile strength, elastic modulus, and elongation at break. According to the ratio of the mechanical properties of the carbon fiber to be tested before and after the friction test, the performance retention rate of the carbon fiber to be tested after friction can be determined.

[0051] In the exemplary embodiments provided by the present disclosure, determining the performance retention rate of the carbon fiber to be tested after friction according to the ratio of the mechanical properties of the carbon fiber to be tested after the friction test to the mechanical properties of the carbon fiber to be tested before the friction test includes: determining the performance retention rate of the carbon fiber to be tested after friction according to the ratio of the tensile strength of the carbon fiber to be tested after the friction test to the tensile strength of the carbon fiber to be tested before the friction test.

[0052] After subjecting the carbon fiber to be tested to a friction test, collect 15 to 30 meters of the carbon fiber to be tested after the friction test, and conduct tensile strength tests on 15 to 30 meters of the carbon fiber to be tested without the friction test (before the friction test) respectively. Among them, the test method of the tensile strength can refer to GB / T3362, GB / T26749 or ASTM D4018. In the process of preparing the test sample strip of the carbon fiber to be tested for tensile strength, the reinforcing sheet can adopt bisphenol A type liquid epoxy resin / polyamine adduct, the curing temperature can be 90°C - 120°C, and the curing time can be 40 min - 70 min.

[0053] According to the measured tensile strengths of the carbon fiber to be tested after the friction test and the carbon fiber to be tested without the friction test, through: the performance retention rate of the carbon fiber to be tested after friction = the tensile strength of the carbon fiber to be tested after the friction test ÷ the tensile strength of the carbon fiber to be tested without the friction test × 100%, the performance retention rate of the carbon fiber to be tested after friction can be calculated, that is, the performance retention rate of the carbon fiber to be tested after friction quantitatively characterized by the tensile strength.

[0054] In the exemplary embodiments provided by the present disclosure, determining the performance retention rate of the carbon fiber to be tested after friction according to the ratio of the mechanical properties of the carbon fiber to be tested after the friction test to the mechanical properties of the carbon fiber to be tested before the friction test includes: determining the performance retention rate of the carbon fiber to be tested after friction according to the ratio of the elastic modulus of the carbon fiber to be tested after the friction test to the elastic modulus of the carbon fiber to be tested before the friction test.

[0055] After subjecting the carbon fiber to be tested to a friction test, collect 15 to 30 meters of the carbon fiber to be tested after the friction test and 15 to 30 meters of the carbon fiber to be tested without the friction test (before the friction test), and conduct elastic modulus tests on them respectively. Among them, the test method of the elastic modulus can refer to GB / T3362, GB / T26749 or ASTM D4018. During the process of preparing the test spline of the carbon fiber to be tested for the elastic modulus, the reinforcing sheet can adopt bisphenol A liquid epoxy resin / polyamine adduct, the curing temperature can be 90°C to 120°C, and the curing time can be 40 min to 70 min.

[0056] According to the measured elastic moduli of the carbon fiber to be tested after the friction test and the carbon fiber to be tested without the friction test, through: the performance retention rate of the carbon fiber to be tested after friction = the elastic modulus of the carbon fiber to be tested after the friction test ÷ the elastic modulus of the carbon fiber to be tested without the friction test × 100%, the performance retention rate of the carbon fiber to be tested after friction can be calculated, that is, the performance retention rate of the carbon fiber to be tested after friction quantitatively characterized by the elastic modulus.

[0057] In the exemplary embodiments provided in the present disclosure, determining the performance retention rate of the carbon fiber to be tested after friction according to the ratio of the mechanical properties of the carbon fiber to be tested after the friction test and the carbon fiber to be tested before the friction test includes: determining the performance retention rate of the carbon fiber to be tested after friction according to the ratio of the elongation at break of the carbon fiber to be tested after the friction test and the elongation at break of the carbon fiber to be tested before the friction test.

[0058] After subjecting the carbon fiber to be tested to a friction test, collect 15 to 30 meters of the carbon fiber to be tested after the friction test and 15 to 30 meters of the carbon fiber to be tested without the friction test (before the friction test), and conduct elongation at break tests on them respectively. Among them, the test method of the elongation at break can refer to GB / T3362, GB / T26749 or ASTM D4018. During the process of preparing the test spline of the carbon fiber to be tested for the elongation at break, the reinforcing sheet can adopt bisphenol A liquid epoxy resin / polyamine adduct, the curing temperature can be 90°C to 120°C, and the curing time can be 40 min to 70 min.

[0059] According to the measured elongation at breaks of the carbon fiber to be tested after the friction test and the carbon fiber to be tested without the friction test, through: the performance retention rate of the carbon fiber to be tested after friction = the elongation at break of the carbon fiber to be tested after the friction test ÷ the elongation at break of the carbon fiber to be tested without the friction test × 100%, the performance retention rate of the carbon fiber to be tested after friction can be calculated, that is, the performance retention rate of the carbon fiber to be tested after friction quantitatively characterized by the elongation at break.

[0060] It should be noted that for the quantitative characterization of the performance retention rate of the carbon fiber to be tested after friction, one or more of the tensile strength, elastic modulus, and elongation at break can be used. For example, the performance retention rate of the carbon fiber to be tested after friction can be quantitatively characterized by the tensile strength, or it can also be quantitatively characterized by the tensile strength, elastic modulus, and elongation at break together.

[0061] In the exemplary embodiments provided by the present disclosure, the test method further includes: obtaining the amount of fuzz on the carbon fiber to be tested after the friction test.

[0062] After the carbon fiber to be tested is towed through the friction of a preset friction roller set, the fuzz of the carbon fiber to be tested after the friction test is collected to obtain the amount of fuzz on the carbon fiber to be tested after the friction test. For example, a certain length (for example, it can be 50 meters) of the carbon fiber to be tested after the friction test is towed through a fuzz collection mechanism (such as polyester cotton), and according to the ratio of the weight of the fuzz collected by the fuzz collection mechanism to the length of the carbon fiber to be tested towed through the fuzz collection mechanism, the amount of fuzz on the carbon fiber to be tested after the friction test can be determined. The amount of fuzz on the carbon fiber to be tested can also characterize the performance retention rate after the carbon fiber is rubbed. For example, a large amount of fuzz indicates a large amount of damage to the carbon fiber after friction, so the performance retention rate after friction is low; a small amount of fuzz indicates a small amount of damage to the carbon fiber after friction, so the performance retention rate after friction is high.

[0063] The exemplary embodiments of the present disclosure provide a test device for the performance retention rate of carbon fiber after friction, as Figure 2 shown, the test device 100 includes a pay-off mechanism 10, a take-up mechanism 20, a control system 30, and a friction system 40. Among them, the pay-off mechanism 10 is used to pay off the carbon fiber 50 to be tested, the take-up mechanism 20 is used to take up the carbon fiber 50 to be tested, the control system 30 is used to control the tension and traction speed of the carbon fiber 50 to be tested, and the friction system 40 is arranged between the pay-off mechanism 10 and the take-up mechanism 20 and is used to perform a friction test on the carbon fiber 50 to be tested.

[0064] The friction test on the carbon fiber to be tested can be a friction test in which the carbon fiber to be tested simulates the actual processing conditions on-site. For example, when a certain type or batch of carbon fiber is woven and processed, if it is necessary to measure the performance retention rate of the carbon fiber of this type or batch after friction during the weaving and processing process, then the carbon fiber of this type or batch can be taken as the carbon fiber to be tested, and traction friction can be carried out under the conditions of simulated weaving and processing to obtain the performance retention rate of the carbon fiber to be tested after the friction test.

[0065] In this embodiment, the unwinding mechanism 10 unwinds the carbon fiber 50 to be tested, the winding mechanism 20 winds up the carbon fiber 50 to be tested, and the control system 30 controls the tension and traction speed of the carbon fiber 50 to be tested to simulate the tension and traction speed in the actual on-site carbon fiber processing process, and the carbon fiber 50 to be tested is tractioned through the friction system 40 for friction testing. According to the ratio of the mechanical properties of the carbon fiber to be tested after the friction test to the carbon fiber to be tested before the friction test, the performance retention rate of the carbon fiber to be tested after friction can be determined. Through the testing device provided in this embodiment, it is possible to accurately simulate the traction, operation and wear conditions in the actual on-site carbon fiber processing process, realize the quantitative testing of the performance retention rate of the carbon fiber after friction, and the structure of the testing device is simple and can be applied to the testing of the performance retention rate of carbon fibers with different specifications and qualities. Exemplarily, the control system 30 can be a plurality of drive shafts. The control system 30 can control the tension of the carbon fiber 50 to be tested to be 50-100 N and the traction speed to be 0-10 m / min. The control system 30 controls the tension of the carbon fiber 50 to be tested during the traction friction test to be 50-100 N, which can ensure that the stress state of the carbon fiber 50 to be tested during the friction test is close to the stress condition in the actual carbon fiber processing process, making the friction test results more reliable and repeatable. For example, the control system 30 can control the tension of the carbon fiber 50 to be tested to be 50 N, 70 N, 90 N or 100 N. The control system 30 can also control the tension of the carbon fiber 50 to be tested to be any value between the exemplary tensions. For example, the control system 30 can also control the tension of the carbon fiber 50 to be tested to be any value between 60-90 N. The control system 30 controls the traction speed of the carbon fiber 50 to be tested during the traction friction test to be 0-10 m / min, which can avoid the problem that the carbon fiber 50 to be tested is not in sufficient frictional contact with the preset friction roller set due to too fast traction speed. For example, the control system 30 can control the traction speed of the carbon fiber 50 to be tested to be 0 m / min (static friction), 3 m / min, 6 m / min or 10 m / min. The control system 30 can also control the traction speed of the carbon fiber 50 to be tested to be any value between the exemplary traction speeds. For example, the control system 30 can also control the traction speed of the carbon fiber 50 to be tested to be any value between 2-8 m / min.

[0066] In the exemplary embodiment provided by the present disclosure, the friction system 40 includes a preset friction roller set 41, and the preset friction roller set 41 includes 6-20 friction rollers 42; when the carbon fiber 50 to be tested passes through each friction roller 42, the included angle between the carbon fibers 50 to be tested on both sides of the friction roller 42 is 30-150°.

[0067] In this embodiment, the friction system 40 includes a preset friction roller group 41. The preset friction roller group 41 includes 6 to 20 friction rollers 42. When the carbon fiber 50 to be tested is traction-passed through the 6 to 20 friction rollers 42 during the friction test, the wear condition of the actual carbon fiber continuously passing through the friction rollers or contact points on-site is simulated through multiple frictions (for example, each time passing through a friction roller 42 is a bending friction). The preset friction roller group 41 including 6 to 20 friction rollers 42 can avoid insufficient friction times of the carbon fiber 50 to be tested caused by too few friction rollers 42, which cannot reflect the real friction damage, and can also avoid over-amplifying the friction damage caused by too many friction rollers 42, exceeding the on-site actual scenario requirements. For example, the preset friction roller group 41 can include 6, 10, 15 or 20 friction rollers 42. The number of friction rollers 42 included in the preset friction roller group 41 can also be any value between the exemplary numbers of friction rollers 42. For example, the number of friction rollers 42 included in the preset friction roller group 41 can also be any value between 8 and 15.

[0068] In this embodiment, when the carbon fiber 50 to be tested passes through each friction roller 42, the included angle between the carbon fibers 50 to be tested on both sides of the friction roller 42 is 30° to 150°. Thus, by adjusting the contact arc between the carbon fiber 50 to be tested and the friction roller 42, the shear force and normal force of the friction between the carbon fiber 50 to be tested and the friction roller 42 can be controlled to simulate different on-site actual friction conditions, ensuring that the test results can reflect the performance retention ability of the carbon fiber under complex working conditions. For example, the included angle between the carbon fibers 50 to be tested on both sides of the friction roller 42 can be set to 30°, 60°, 90° or 150°. The included angle between the carbon fibers 50 to be tested on both sides of the friction roller 42 can also be any value between the exemplary included angles. For example, the included angle between the carbon fibers 50 to be tested on both sides of the friction roller 42 can also be any value between 60° and 120°. It should be noted that the friction roller 42 in the preset friction roller group 41 can be a detachable structure. For example, according to the on-site actual processing conditions of the carbon fiber to be simulated, the friction roller 42 can be disassembled or its position can be changed (such as changing the height) so that the preset friction roller group 41 can be used to simulate different friction test conditions.

[0069] In the exemplary embodiment provided by the present disclosure, the test device 100 further includes a hair collecting mechanism 80, which is arranged between the friction system 40 and the winding mechanism 20. The hair collecting mechanism 80 is used to collect the hairs of the carbon fiber 50 to be tested after the friction test.

[0070] In this embodiment, a fuzz collection mechanism 80 is provided between the friction system 40 and the winding mechanism 20. After the to-be-tested carbon fiber 50 passes through the friction of the preset friction roller set 41, the fuzz of the to-be-tested carbon fiber 50 after the friction test can be collected to obtain the fuzzing amount of the to-be-tested carbon fiber 50 after the friction test. Exemplarily, the fuzz collection mechanism 80 can be polyester cotton. After the to-be-tested carbon fiber 50 with a certain length (for example, 50 meters) after the friction test is drawn through the polyester cotton, the polyester cotton can collect the fuzz shed by the to-be-tested carbon fiber 50 after the friction test. According to the ratio of the weight of the fuzz collected by the polyester cotton to the length of the to-be-tested carbon fiber 50 drawn through the polyester cotton, the fuzzing amount of the to-be-tested carbon fiber 50 after the friction test can be determined. The fuzzing amount of the to-be-tested carbon fiber 50 can also characterize the performance retention rate of the carbon fiber after friction. For example, a large fuzzing amount indicates large damage to the carbon fiber after friction, so the performance retention rate after friction is low; a small fuzzing amount indicates small damage to the carbon fiber after friction, so the performance retention rate after friction is high.

[0071] To more clearly explain and illustrate the technical solution of the present disclosure, a specific embodiment of the test device for the performance retention rate of carbon fiber after friction provided by the exemplary embodiment of the present disclosure is given for implementing the test method for the performance retention rate of carbon fiber after friction provided by the exemplary embodiment of the present disclosure.

[0072] For the evaluation of the wear resistance of carbon fiber, the to-be-tested SYT49S-12K carbon fiber is unwound by the unwinding mechanism and wound by the winding mechanism. The tension of the to-be-tested SYT49S-12K carbon fiber is controlled to be 60 N and the traction speed is 5 m / min through the control system. The to-be-tested SYT49S-12K carbon fiber is drawn through four friction rollers with an angle of 120° between the adjacent two sides of the to-be-tested SYT49S-12K carbon fiber, and four friction rollers with an angle of 90° between the adjacent two sides of the to-be-tested SYT49S-12K carbon fiber. Then the to-be-tested SYT49S-12K carbon fiber is drawn through the polyester cotton, and the weight increase of the polyester cotton after passing through 50 meters of the to-be-tested SYT49S-12K carbon fiber is measured, and the fuzzing amount of the to-be-tested SYT49S-12K carbon fiber is obtained as 5.6 mg / 50 m. Ten meters of the to-be-tested SYT49S-12K carbon fiber after the friction test are collected for measuring the mechanical properties of the to-be-tested SYT49S-12K carbon fiber after the friction test.

[0073] The SYT49S-12K carbon fiber to be tested after the friction test and the SYT49S-12K carbon fiber to be tested without the friction test are mechanically sampled with reference to GB / T3362. After the curing of the sampled spline is completed, a bisphenol A liquid epoxy resin / polyamine adduct = 2:1 is used to paste and reinforce the sheet, where the curing temperature is 90 °C and the curing time is 70 min. After the curing is completed, the test specimens are obtained, and an electronic tensile machine is used to test the tensile strength and elastic modulus of the test specimens without the friction test and the test specimens after the friction test respectively.

[0074] The tensile strength of the test specimen without the friction test is 5216 MPa, the elastic modulus is 243 GPa, and the elongation at break is 2.1%.

[0075] The tensile strength of the test specimen after the friction test is 5145 MPa, the elastic modulus is 243 GPa, and the elongation at break is 2.1%.

[0076] Calculation of the retention rate of properties after friction:

[0077] The retention rate of tensile strength after friction = 5145 MPa ÷ 5216 MPa * 100% = 98.6%.

[0078] The retention rate of elastic modulus after friction = 243 GPa ÷ 243 GPa * 100% = 100%.

[0079] The retention rate of elongation at break after friction = 2.1% ÷ 2.1% * 100% = 100%.

[0080] The test method for the retention rate of properties of carbon fiber after friction provided by the exemplary embodiments of the present disclosure can quantitatively and accurately characterize the retention rate of properties of the carbon fiber to be tested after friction by simulating the friction situation during the actual processing of the carbon fiber on site, performing a friction test, and based on the ratio of the mechanical properties of the carbon fiber to be tested before and after the friction test, providing a reliable basis for the structural design of carbon fiber composites and promoting the wide application of carbon fiber. This test method is simple, efficient, and easy to operate.

[0081] The content described above can be implemented alone or in various combinations, and these variant ways are all within the protection scope of the present disclosure.

[0082] Finally, it should be noted that in this article, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements but also includes other elements not explicitly listed, or further includes elements inherent to such process, method, article or device.

[0083] The above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than to limit them. Although the present disclosure has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; 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 various embodiments of the present disclosure.

Claims

1. A method for testing the performance retention rate of carbon fiber after friction, characterized in that: The test method includes: Subject the carbon fiber to be tested to a friction test; The performance retention rate of the carbon fiber to be tested after friction is determined according to the ratio of the mechanical properties of the carbon fiber to be tested after the friction test to the mechanical properties of the carbon fiber to be tested before the friction test.

2. The method for testing the performance retention rate of carbon fiber after friction according to claim 1, characterized in that: The mechanical properties include tensile strength, elastic modulus and elongation at break.

3. The method for testing the performance retention rate of carbon fiber after friction according to claim 2, characterized in that: Determining the performance retention rate of the carbon fiber to be tested after friction according to the ratio of the mechanical properties of the carbon fiber to be tested after the friction test to the mechanical properties of the carbon fiber to be tested before the friction test includes: Determining the performance retention rate of the carbon fiber to be tested after friction according to the ratio of the tensile strength of the carbon fiber to be tested after the friction test to the tensile strength of the carbon fiber to be tested before the friction test; and / or, Determining the performance retention rate of the carbon fiber to be tested after friction according to the ratio of the mechanical properties of the carbon fiber to be tested after the friction test to the mechanical properties of the carbon fiber to be tested before the friction test includes: Determining the performance retention rate of the carbon fiber to be tested after friction according to the ratio of the elastic modulus of the carbon fiber to be tested after the friction test to the elastic modulus of the carbon fiber to be tested before the friction test; and / or, Determining the performance retention rate of the carbon fiber to be tested after friction according to the ratio of the mechanical properties of the carbon fiber to be tested after the friction test to the mechanical properties of the carbon fiber to be tested before the friction test includes: The performance retention rate of the carbon fiber to be tested after friction is determined according to the ratio of the elongation at break of the carbon fiber to be tested after the friction test to the elongation at break of the carbon fiber to be tested before the friction test.

4. The method for testing the performance retention rate of carbon fiber after friction according to claim 1, characterized in that: The friction test of the carbon fiber to be tested comprises: The carbon fiber to be tested is pulled under preset conditions and passed through a preset friction roller set to perform a friction test.

5. The method for testing the performance retention rate of carbon fiber after friction according to claim 4, characterized in that: The preset conditions include: a tension of 50 to 100 N and a pulling speed of 0 to 10 m / min.

6. The method for testing the performance retention rate of carbon fiber after friction according to claim 4, characterized in that: The preset friction roller group includes 6 to 20 friction rollers; when the carbon fiber to be tested passes through each friction roller, the angle between the carbon fiber to be tested on both sides of the friction roller is 30 to 150 degrees.

7. The method for testing the performance retention rate of carbon fiber after friction according to claim 1, characterized in that: The test method also includes: The fuzzing amount of the carbon fiber to be tested after the friction test is obtained.

8. A testing device for the performance retention rate of carbon fiber after friction, characterized in that: The testing device comprises: An unwinding mechanism, used for unwinding the carbon fiber to be tested; A winding mechanism, used for winding the carbon fiber to be tested; A control system, used to control the tension and pulling speed of the carbon fiber to be tested; A friction system is arranged between the unwinding mechanism and the winding mechanism, and the friction system is used to perform a friction test on the carbon fiber to be tested.

9. The testing device for the retention rate of carbon fiber performance after friction according to claim 8, characterized in that: The friction system includes a preset friction roller group, which includes 6 to 20 friction rollers; when the carbon fiber to be tested passes through each friction roller, the angle between the carbon fiber to be tested on both sides of the friction roller is 30 to 150 degrees.

10. The testing device for the retention rate of carbon fiber performance after friction according to claim 8, characterized in that: The testing device further comprises a hair collecting mechanism, which is arranged between the friction system and the winding mechanism, and the hair collecting mechanism is used to collect hair of the carbon fiber to be tested after the friction test.

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