A fixture device, test system and method for measuring the interfacial bond strength of a coating to a substrate

Abstract

The application discloses a clamp device, a test system and a method for measuring the bonding strength of a coating and a substrate. The clamp device comprises an upper clamp and a flat-bottom cylindrical pin I, wherein the upper clamp is used for clamping a sample to be measured, and the flat-bottom cylindrical pin I is used for bonding and fixing a coating surface of the sample to be measured. The upper clamp comprises a cylindrical pin II, a sliding part, a clamping assembly and a screw assembly. The cylindrical pin II is perpendicularly and threadedly connected with an upper surface of the sliding part. The clamping assembly is slidably fixed on the sliding part through the screw assembly and is used for clamping the sample to be measured. The bonding strength between the coating and the substrate at the relative position of the connecting piece of the material to be measured is tested under the pulling action of a pulling test mechanism. The clamp device and the method provided by the application can reduce test influencing factors, ensure that the force direction is normal during pulling, and improve test precision and repeatability.

Description

TECHNICAL FIELD

[0001] The present application relates to a clamp device, a test system and a method for measuring the interfacial bonding strength of a coating and a substrate, belonging to the field of material performance testing. BACKGROUND

[0002] In many technical fields, in order to improve the appearance, texture, function and other aspects of the product, the material surface needs to be coated to obtain a composite material with excellent comprehensive performance. Among them, the interfacial bonding strength of the coating and the substrate reflects the ability of the coating to separate from the substrate, and strong interfacial bonding strength is the basis for ensuring that the composite material can be processed and applied. Usually, tensile testing can be used. However, due to the complexity of the existing clamp device and test method, high clamping requirements, harsh test conditions and other problems, it is difficult to achieve efficient and accurate measurement of the interfacial bonding strength. For example, patent 202111135025.9 proposes a test method in which two tensile heads are symmetrically arranged on both sides of the substrate coating sample, and the working parts of the two tensile heads are respectively bonded to the substrate and the coating through an adhesive. This method often results in a bonding strength between the adhesive and the substrate being greater than the bonding strength between the adhesive and the coating, which causes the cylindrical pin to be pulled off from the side of the substrate during tensile testing, increasing the uncertainty of the test, and the effective bonding strength data between the coating and the substrate cannot be obtained. In addition, this method has a very strict requirement for the symmetry of the tensile heads on both sides of the test sample, which is difficult to control manually, and seriously reduces the test efficiency and data reliability. Therefore, a new technical solution is needed to solve the above problems. SUMMARY

[0003] To overcome the shortcomings of the prior art, the present application provides a new clamp device that tests the interfacial bonding strength between the coating and the substrate of the test material at the relative position of the connecting piece under the tensile action of the tensile testing mechanism, which can reduce the test influencing factors, ensure that the force direction is normal during tensile testing, improve the test precision and repeatability, and improve the tensile testing efficiency and safety. The clamp device can be quickly replaced with test samples and is suitable for testing the interfacial bonding strength between the coating and the substrate prepared by various methods, with a wide test range.

[0004] In one aspect of the present application, a clamp device for measuring the interfacial bonding strength of a coating and a substrate is provided, which tests the interfacial bonding strength between the coating and the substrate of the test material at the relative position of the connecting piece under the tensile action of the tensile testing mechanism.

[0005] The clamp device comprises an upper clamp and a flat-bottomed cylindrical pin I, wherein the upper clamp is used to clamp the test sample, and the flat-bottomed cylindrical pin I is used to bond and fix the coating surface of the test sample.

[0006] The upper clamp comprises a cylindrical pin II, a sliding component, a clamping assembly and a screw assembly.

[0007] The cylindrical pin II is perpendicularly and threadedly connected with the upper surface of the sliding component;

[0008] The clamping assembly is slidably fixed on the sliding component by the screw assembly, and is used for clamping the sample to be tested.

[0009] As a specific embodiment, the screw assembly includes two screws, which are respectively arranged at two ends of the sliding component and are connected with the clamping assembly.

[0010] Optionally, the cylindrical pin II is provided with an A end and a B end;

[0011] The A end is a non-threaded end, and the B end is a threaded end;

[0012] The B end is threadedly connected with the sliding component.

[0013] In the present application, the length and diameter of the cylindrical pin II can be adjusted according to the use requirement, the non-threaded end (A end) of the cylindrical pin II is used for connecting the upper clamp block of the testing machine, and the threaded end (B end) is connected with the sliding component;

[0014] Optionally, the sliding component is in the shape of “|”;

[0015] The center of the upper surface of the sliding component is provided with an internally threaded circular hole I, and the B end of the cylindrical pin II is tightly connected with the internally threaded circular hole I; wherein the size of the internally threaded circular hole I is matched with the cylindrical pin II;

[0016] The length of the upper surface of the sliding component is greater than the length or width of the sample to be tested;

[0017] The area of the upper surface of the sliding component is greater than the bottom area of the cylindrical pin II.

[0018] In the present application, the width and height of the upper surface of the sliding component need to ensure that the mechanical properties of the testing clamp are sufficient for the tensile test.

[0019] Optionally, the side surface I and the side surface II of the sliding component are parallel to each other and have equal surface areas;

[0020] The side surface I and the side surface II are respectively perpendicular to the upper surface;

[0021] The center of the side surface I and the center of the side surface II are respectively provided with a through internally threaded circular hole II.

[0022] Optionally, the clamping assembly includes a left clamping unit and a right clamping unit which are mirror images;

[0023] The left clamping unit is in the shape of “L”;

[0024] The left clamping unit is vertically installed with the sliding component, and the left clamping unit and the right clamping unit of the clamping assembly are installed in parallel with each other.

[0025] Optionally, the upper surface of the left clamping unit is wider than the upper surface of the sliding component.

[0026] The side surface of the left clamping unit is provided with a through hole for sliding of the sliding component.

[0027] The size of the through hole is matched with the size of the sliding component, so that the sliding component can be just passed through and freely slide.

[0028] Optionally, the screw assembly includes a screw I and a screw II with equal lengths.

[0029] The end of the screw rod of the screw I and the screw II is in contact with the clamping assembly for fixing the position of the clamping assembly.

[0030] The screw I passes through the inner threaded round hole II of the side surface I of the sliding part, and the upper surface of the sliding component is kept parallel.

[0031] The screw II passes through the inner threaded round hole II of the side surface II of the sliding part, and the upper surface of the sliding component is kept parallel.

[0032] As a specific embodiment, the two screws are vertically welded with the long end (side surface) of the clamping assembly respectively, pass through the inner threaded round hole II of the side surface of the sliding component, and the upper surface of the sliding component is kept parallel.

[0033] Optionally, the bottom area of the flat bottom cylindrical pin I is smaller than the area of the coating surface of the sample to be measured.

[0034] The length of the flat bottom cylindrical pin I is 50-100 mm.

[0035] The bonding surface of the flat bottom cylindrical pin I and the coating surface of the sample to be measured is circular.

[0036] In another aspect of the present application, a test system for measuring the interfacial bonding strength of a coating and a substrate is provided, which includes the clamp device for measuring the interfacial bonding strength of a coating and a substrate, a sample to be measured, and an electronic universal material testing machine.

[0037] The electronic universal material testing machine includes an upper clamp block and a lower clamp block.

[0038] The A end of the cylindrical pin II is connected with the upper clamp block of the electronic universal material testing machine.

[0039] The clamping assembly clamps and fixes the sample to be measured.

[0040] The C end of the flat-bottomed cylindrical pin I is connected with the lower clamp block of the electronic universal material testing machine, and the D end is bonded with the coating surface of the sample to be tested.

[0041] In another aspect of the present application, a test method for measuring the interfacial bonding strength of a coating and a substrate is provided, which uses the test system described above.

[0042] The test method comprises:

[0043] (1) bonding the D end of the flat-bottomed cylindrical pin I with the coating surface of the sample to be tested through an adhesive, and measuring the diameter d of the D end of the flat-bottomed cylindrical pin I;

[0044] Wherein, the selection of the adhesive should follow the principle that the bonding strength between the adhesive and the coating and the flat-bottomed cylindrical pin is greater than the bonding strength between the coating and the substrate, and the adhesive is allowed to solidify completely;

[0045] (2) turning on the electronic universal material testing machine, and setting the test speed and the preload according to the selected sample to be tested;

[0046] (3) fixing the A end of the cylindrical pin II of the clamp device with the upper clamp block of the electronic universal material testing machine;

[0047] (4) fixing the sample to be tested through the sliding part, ensuring that the flat-bottomed cylindrical pin I and the cylindrical pin II are in a vertical symmetrical position, and fixing the C end of the flat-bottomed cylindrical pin I with the lower clamp block of the electronic universal material testing machine;

[0048] (5) clearing the initial force value of the electronic universal material testing machine, starting the test, and using the constant speed displacement mode for stretching until the coating surface of the sample to be tested is stretched and separated from the substrate of the sample to be tested and is damaged, and recording the peak load F c at the time of damage;

[0049] (6) calculating the tensile bonding strength σ

[0050]

[0051] Wherein, F c is the peak load at the time of peeling off the coating surface from the substrate surface and damage, and d is the diameter of the flat-bottomed cylindrical pin I.

[0052] As a specific embodiment, the test method comprises:

[0053] S1, stick the flat-bottom cylindrical pin to the sample coating to be tested by adhesive, the selection of the adhesive should follow the principle that the bonding strength between the adhesive and the flat-bottom cylindrical pin and the coating is greater than the bonding strength between the coating and the substrate, and wait for the adhesive to solidify completely;

[0054] S2, adjust the position of the clamping assembly and check the clamping effect;

[0055] S3, preparation before experiment: measure the diameter of the flat-bottom cylindrical pin of the sample using a vernier caliper, and record it as d;

[0056] S4, turn on the electronic universal material testing machine, select the appropriate test program, and set the appropriate test speed and preload according to the sample;

[0057] S5, put the unthreaded end of the upper clamp cylindrical pin into the clamp block of the electronic universal material testing machine, and close the clamp of the electronic universal material testing machine;

[0058] S6, move the crossbeam of the clamping clamp of the electronic universal material testing machine upward to an appropriate height, so that the sample can be pushed horizontally into the sliding part of the clamp, and ensure that the flat-bottom cylindrical pin of the sample to be tested is as symmetric as possible with the threaded cylindrical pin at one end of the upper clamp, and then move the crossbeam of the electronic universal material testing machine downward, so that the sample enters the clamp block of the lower clamp of the electronic universal material testing machine;

[0059] S7, clear the initial force value of the electronic universal material testing machine, click start test, and use the constant speed displacement method to stretch until the flat-bottom cylindrical pin and the coating surface of the sample to be tested are stretched and separated, and record the peak load F c when the damage occurs;

[0060] S8, calculate the tensile bonding strength σ

[0061]

[0062] between the flat-bottom cylindrical pin and the coating surface of the sample to be tested according to formula (1) c , where F is the peak load when the coating is separated from the surface of the substrate, and d is the diameter of the contact area between the flat-bottom cylindrical pin and the coating.

[0063] The beneficial effects that can be produced by the present application include:

[0064] The present application divides the clamp device into two parts, i.e. an upper clamp and a flat-bottom cylindrical pin. The upper clamp is first installed in the clamp block of the universal testing machine, and then the flat-bottom cylindrical pin to be tested is installed in the clamp block of the lower clamp of the universal testing machine. Since the clamp blocks of the upper and lower clamps of the universal testing machine are in symmetrical positions, the flat-bottom cylindrical pin to be tested and the outer threaded cylindrical pin at one end of the upper clamp are also automatically symmetrical, which improves the clamping effect of the clamp on the test piece and ensures that the force applied to the coating during the tensile test is along the normal direction, so that the test result is accurate, reliable and repeatable. Meanwhile, since the upper clamp does not need to be disassembled during the test, only the sample to be tested needs to be replaced during the tensile test, so that the repeated test can be quickly performed, the operation is simple, and the clamp is convenient to use. The clamp is suitable for testing the bonding strength between the coating and the substrate prepared by various methods, and has a wide application range. BRIEF DESCRIPTION OF DRAWINGS

[0065] Figure 1 It is a schematic view of the upper clamp of the clamp device in the embodiment of the present application.

[0066] Figure 2 It is a top view of the clamp device. Figure 1

[0067] Figure 3 It is a left (right) view of the clamp device. Figure 1

[0068] Figure 4 It is a schematic view of the test sample and the flat-bottom cylindrical pin of the clamp device after bonding.

[0069] Figure 5 It is a bottom view of the clamp device. Figure 4

[0070] Figure 6 It is a schematic view of the test sample and the clamp device after assembly.

[0071] PARTS AND LIST OF REFERENCE NUMBERS

[0072] 1. An outer threaded cylindrical pin at one end; 2. A sliding part; 3. A clamping assembly; 4. Two screws; 5. A flat-bottom cylindrical pin; 6. A test sample; 7. A substrate; 8. A coating; 9. An adhesive; 10. The upper surface of the sliding part; 11. An internally threaded hole; 12. An internally threaded hole; 13. An oblong hole; 14. A test surface area; 15. A bonding surface. DETAILED DESCRIPTION

[0073] The present application will be described in detail below in combination with the embodiments, but the present application is not limited to these embodiments.

[0074] Unless otherwise specified, the raw materials in the embodiments of the present application are purchased through commercial channels.

[0075] Example 1​​​

[0076] The embodiment of the present application provides a fixture device for measuring the interfacial bonding strength between a coating and a substrate, as Figures 1-6 shown. The fixture device includes a cylindrical pin 1 with an external thread at one end, a sliding member 2, a clamping assembly 3, two screws 4, a flat-bottom cylindrical pin 5, and a test sample 6. Among them:

[0077] The preparation materials of the cylindrical pin 1 with an external thread at one end, the sliding member 2, the clamping assembly 3, the two screws 4, and the flat-bottom cylindrical pin 5 are preferably steel materials.

[0078] Before the test, the upper fixture is connected to the upper fixture block of the universal testing machine through the non-threaded end of the cylindrical pin 1 with an external thread at one end.

[0079] The test sample 6 includes a substrate 7 and a coating 8 bonded together. One end of the flat-bottom cylindrical pin 5 is bonded to the coating 7 of the test sample through 9, placed on the clamping assembly 3 of the upper fixture, and the other end is connected to the lower fixture block of the universal testing machine.

[0080] The sliding member 2 is in the shape of "冖". The area of its upper surface 10 is required to be larger than the bottom area of the cylindrical pin 1 with an external thread at one end. An internally threaded circular hole 11 is provided at the center of the upper surface 10, which is matched with the cylindrical pin 1 with an external thread at one end;

[0081] The areas on both sides of the sliding member 2 are equal and parallel to each other, perpendicular to the upper surface 10, and internally threaded circular holes 12 are provided at the centers of both sides;

[0082] [[ID=二十]]The length of the upper surface 10 of the sliding member 2 should be greater than the length or width of the test sample 6, and its width and height need to ensure that the mechanical properties of the test fixture are sufficient for the pull-out test.

[0083] The clamping assembly 3 is L-shaped. Its width should be greater than the width of the upper surface 10 of the sliding member. A rectangular hole 13 is opened on its side surface. The size of the hole is required to just pass through the sliding member and be able to slide freely; "0000190"

[0084] [[ID=2八千]]The long end of the clamping assembly 3 is perpendicularly installed with the upper surface 10 of the sliding member, and the two parts of the clamping assembly are installed parallel to each other;

[0085] The two screws 4 are perpendicularly welded to the long ends of the clamping assembly 3 respectively, pass through the internally threaded circular holes 12 on the side surface of the sliding member, and are parallel to the upper surface 10 of the sliding member. The lengths of the two screws 4 should be equal; [[ID=三十二]] <000095> The bottom area of the flat-bottom cylindrical pin 5 should be smaller than the test surface area 14 of the test sample. There is no limit to its length. The bonding surface 15 of the flat-bottom cylindrical pin 5 with the surface fourteen of the test sample coating is circular. [[ID=三十六]]

[0087] Example 2

[0088] The embodiment uses the fixture device provided in Embodiment 1 to test the interfacial bonding strength between the coating and the substrate, and the test method for the interfacial bonding strength between the coating and the substrate is as shown in Figures 1-6 The method comprises the following steps:

[0089] S1, bonding the flat-bottom cylindrical pin 5 to the coating of the sample to be tested through the adhesive 9, and waiting for the adhesive to be completely cured. The selection of the adhesive 9 should follow the principle that the bonding strength between the adhesive 9 and the flat-bottom cylindrical pin 5 and the coating is greater than the bonding strength between the coating 8 and the substrate 7;

[0090] S2, adjusting the position of the clamping assembly 3 and checking the clamping effect;

[0091] S3, preparation before the experiment: measuring the diameter of the flat-bottom cylindrical pin 5 of the sample by using the vernier caliper, and recording the diameter as d;

[0092] S4, starting the electronic universal material testing machine, selecting a suitable test program, and setting a suitable test speed and pre-load force according to the sample to be tested;

[0093] S5, installing the outer-threaded cylindrical pin 1 at one end of the upper clamp without threads into the clamp block of the electronic universal material testing machine, and closing the clamp block of the electronic universal material testing machine;

[0094] S6, moving the crossbeam of the electronic universal material testing machine of the clamping fixture upward to a suitable height, so that the sample can be horizontally pushed into the sliding part 2 of the clamp, and ensuring that the flat-bottom cylindrical pin 5 of the sample to be tested is as symmetrically positioned as possible with the outer-threaded cylindrical pin 1 at one end of the upper clamp, and then moving the crossbeam of the electronic universal material testing machine downward, so that the sample enters between the lower clamp block of the electronic universal material testing machine;

[0095] S7, clearing the initial load value of the electronic universal material testing machine, clicking start test, and performing stretching by using the constant speed displacement mode until the flat-bottom cylindrical pin 5 and the coating surface 8 of the sample to be tested are stretched and separated to be damaged, and recording the load peak value Fc at the time of damage;

[0096] S8, calculating the tensile bonding strength σ between the flat-bottom cylindrical pin and the coating surface of the sample to be tested according to formula (1);

[0097]

[0098] The present application divides the clamp device into two parts, an upper clamp and a flat-bottom cylindrical pin. The upper clamp is first installed in the clamp block of the universal testing machine, and then the flat-bottom cylindrical pin to be tested is installed in the lower clamp block of the universal testing machine. Since the upper and lower clamp blocks of the universal testing machine are at the same central axis position, the flat-bottom cylindrical pin to be tested and the threaded cylindrical pin at one end of the upper clamp are also automatically at the same central axis position, which improves the clamping effect of the clamp on the test piece and ensures that the force applied to the coating during the tensile test is normal, the test result is accurate, reliable and repeatable. At the same time, since the upper clamp does not need to be disassembled during the test, only the sample to be tested needs to be replaced during the tensile test, which can quickly perform repeated tests, is simple to operate and easy to use.

[0099] Example 3 Test of the interfacial bonding strength between the amorphous carbon coating prepared by the plasma enhanced chemical vapor deposition method and polyether ether ketone (PEEK)

[0100] (1) Preparation of amorphous carbon coating on the surface of PEEK

[0101] a. First, the PEEK substrate (size: 20mm x 20mm x 6mm) is cleaned with anhydrous ethanol. The cleaned and dried PEEK substrate is placed in a vacuum chamber with a vacuum degree of less than 2*10 -5 Torr. First, the chamber pressure is set to 20mTorr, and argon gas is introduced into the vacuum chamber at a flow rate of 100sccm. The flow automatic control valve is opened, and the chamber pressure is allowed to reach the set value of 20mTorr. Then, a -500V pulsed negative bias is applied to the PEEK substrate, with a duty cycle of 61.5% and an etching time of 10min.

[0102] b. The bias and argon gas are turned off, and the vacuum is pumped to below 2*10 -5 Torr. 100sccm of acetylene is introduced into the chamber, and the flow automatic control valve is opened. The chamber pressure is allowed to reach the set value of 15mTorr. Then, a -450V pulsed negative bias is applied to the PEEK substrate, with a duty cycle of 61.5% and a deposition time of 65min.

[0103] Through the above steps, an amorphous carbon coating with a thickness of 1500nm is obtained on the surface of the PEEK substrate. The coating appears black.

[0104] (2) Test of the interfacial bonding strength between the coating and the substrate

[0105] a. The end of the flat-bottom cylindrical pin 5 is polished with 1000 grit sandpaper, and the flat-bottom cylindrical pin is bonded to the side of the PEEK with the coating using epoxy resin AB glue 9. A total of 3 test samples are prepared.

[0106] b. Adjust the position of the clamping assembly 3 and check the clamping effect.

[0107] ​​​​​​​​​c、Preparation before experiment: use vernier caliper to measure the diameter of the sample flat-bottom cylindrical pin, the flat-bottom cylindrical pin used in this experiment has a diameter of 9.98mm, 9.99mm, 9.98mm, and a length of 99.99mm, 100.00mm, 99.98mm respectively;

[0108] d、Start the electronic universal material testing machine, select the tensile test program, and set the test speed to 1mm / min and the preload to 1N;

[0109] e、Put the upper clamp end with an external threaded cylindrical pin 1 into the electronic universal material testing machine between the upper clamp blocks, and close the upper clamp of the testing machine;

[0110] f、Move the crossbeam of the electronic universal material testing machine with the clamping clamp upward to a moderate height, so that the sample to be tested can be pushed horizontally into the clamping sliding part, and ensure that the flat-bottom cylindrical pin of the sample to be tested is in a symmetrical position with the upper clamp end with an external threaded cylindrical pin, and then move the crossbeam of the electronic universal material testing machine downward, so that the sample enters between the lower clamp blocks of the testing machine;

[0111] g、Clear the initial force value of the electronic universal material testing machine, click start test, and use the constant speed displacement method to stretch until the flat-bottom cylindrical pin and the surface of the sample coating to be tested are stretched and separated, and record the peak load F at the time of failure; c ; Calculate according to formula (1);

[0112] h、Repeat f-g, and test three samples, the maximum tensile force is 260N, 261N, and 260N respectively, the maximum adhesive stress is 3.34MPa, 3.35MPa, and 3.34MPa respectively, the standard deviation of the three data is 0.005MPa, and the data is stable.

[0113] The above is only an embodiment of the present application, and does not limit the present application in any form. Although the preferred embodiment is disclosed as above, it is not intended to limit the present application. Any skilled person in the art can make some changes or modifications to the disclosed technical content without departing from the scope of the technical solution of the present application, which are equivalent to equivalent embodiments, and are within the scope of the technical solution.

Claims

1. A fixture device for measuring the interfacial bonding strength between a coating and a substrate, characterized in that the fixture device includes: an upper fixture and a flat-bottom cylindrical pin I. Among them, the upper fixture is used to clamp the sample to be tested, and the flat-bottom cylindrical pin I is used to bond and fix the coated surface of the sample to be tested; the upper fixture includes: a cylindrical pin II, a sliding member, a clamping assembly and a screw assembly; the cylindrical pin II has an A end and a B end. The A end is a non-threaded end, and the B end is an externally threaded end. The B end is perpendicular to and threadedly connected to the upper surface of the sliding member; the sliding member is in the shape of "冖", and there is an internally threaded round hole I at the center of its upper surface. The B end of the cylindrical pin II is tightly connected to the internally threaded round hole I, and the length of the upper surface of the sliding member is greater than the length or width of the sample to be tested; the clamping assembly includes a left clamping unit and a right clamping unit arranged mirror-symmetrically. The left clamping unit is in the shape of "L", and the left clamping unit is vertically installed with the sliding member. There is a through hole on the side surface of the left clamping unit for the sliding of the sliding member; the screw assembly includes screw I and screw II with equal lengths. Screw I passes through the internally threaded round hole II on the first side surface of the sliding member and is parallel to the upper surface of the sliding member. Screw II passes through the internally threaded round hole II on the second side surface of the sliding member and is parallel to the upper surface of the sliding member. The ends of the screw rods of screw I and screw II contact and fix the clamping assembly to control the position of the clamping assembly; the bottom area of the flat-bottom cylindrical pin I is smaller than the area of the coated surface of the sample to be tested. The length of the flat-bottom cylindrical pin I is 50 - 100 mm, and the bonding surface between the flat-bottom cylindrical pin I and the coated surface of the sample to be tested is circular.

2. The fixture device according to claim 1, characterized in that the area of the upper surface of the sliding member is greater than the bottom area of the cylindrical pin II.

3. The fixture device according to claim 2, characterized in that the first side surface and the second side surface provided on the sliding member are parallel to each other and have equal surface areas; the first side surface and the second side surface are respectively perpendicular to the upper surface; through-type internally threaded round holes II are provided at the centers of the first side surface and the second side surface respectively.

4. The fixture device according to claim 1, characterized in that the width of the upper surface of the left clamping unit is greater than the width of the upper surface of the sliding member; the size of the through hole is adapted to the size of the sliding member.

5. A test system for measuring the interfacial bonding strength between a coating and a substrate, characterized in that the test system includes the fixture device for measuring the interfacial bonding strength between a coating and a substrate according to any one of claims 1 - 4, a sample to be tested and an electronic universal material testing machine; the electronic universal material testing machine includes an upper fixture block and a lower fixture block; the A end of the cylindrical pin II is connected to the upper fixture block of the electronic universal material testing machine; the clamping assembly clamps and fixes the sample to be tested; The C end of the flat-bottomed cylindrical pin I is connected to the lower clamping block of the electronic universal testing machine, and the D end is bonded to the coating surface of the sample to be tested.

6. A test method for measuring the interfacial bonding strength between a coating and a substrate, characterized in that, The testing method employs the testing system described in claim 5; The testing method includes: (1) Bond the D end of the flat-bottomed cylindrical pin I to the coating surface of the sample to be tested with an adhesive, and measure the diameter d of the D end of the flat-bottomed cylindrical pin I; (2) Turn on the electronic universal testing machine and set the test speed and preload according to the selected sample to be tested; (3) Fix the A end of the cylindrical pin II of the clamping device to the upper clamping block of the electronic universal material testing machine; (4) Fix the sample to be tested by the sliding component to ensure that the flat-bottomed cylindrical pin I and the cylindrical pin II are in a vertically symmetrical position, and fix the C end of the flat-bottomed cylindrical pin I to the lower clamping block of the electronic universal material testing machine. (5) Zero the initial force value of the electronic universal testing machine and start the test. Use constant velocity displacement to perform tensile testing until the coating of the test sample is tensilely separated from the substrate of the test sample and fails. Record the peak load F at the time of failure. c ; (6) Calculate the tensile bond strength between the flat-bottomed cylindrical pin I and the coating surface of the sample to be tested according to formula (1). = （1） Among them, F c d represents the peak load when the coating peels off from the substrate surface and fails, and d is the diameter of the flat-bottomed cylindrical pin I.

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