Preparation method and application of simple film binding force test sample

Abstract

The invention discloses a preparation method and application of a simple film layer binding force test sample, and the preparation method specifically comprises the following steps: S1, clamping a flat boss of a cylindrical test bar into a groove of a clamp, rotating a locking bolt, enabling the clamp to extrude inwards, and fixing the cylindrical test bar; s2, uniformly smearing an adhesive on the end surface of one cylindrical test bar and bonding the cylindrical test bar with the test piece, and uniformly smearing an adhesive on the end surface of the other cylindrical test bar; s3, pushing the sliding block to prevent the end face of the cylindrical test bar from being adhered to the test piece; s4, locking a limiting nut at the tail end, and keeping the extrusion force between the end surface of the cylindrical test bar and the test piece; and S5, according to the technical parameters of the adhesive, taking down the adhesive after the adhesive is completely cured and reaches the maximum strength, installing the test bar-test piece-test bar combined sample on a testing machine, and carrying out a tension test to obtain the bonding strength of the film layer and the base material, and the method has good applicability for testing the bonding force of the film layer and the base material.

Description

Technical Field

[0001] The invention belongs to the technical field of film layer testing methods and relates to film layer, coating and paint surface bonding strength testing. Background Art

[0002] The measurement of film adhesion has always followed a standard test method to ensure the accuracy and reliability of the data. This method mainly uses a pair of cylindrical test bars, the end faces or the entirety of which are covered with film layers and bonded to each other by a special adhesive. When the adhesive is fully cured and reaches its maximum bonding strength, the test bar-test bar sample is installed in a tensile testing machine for tensile testing.

[0003] However, faced with the various clamping methods of tensile testing machines, the traditional single cylindrical test rod is slightly lacking in versatility. More importantly, when testing the bonding strength between the film layer and the substrate, it is expected that the material of the test rod is consistent with the substrate material of the coated product, so as to truly reflect the bonding strength between the film layer and the substrate. However, some problems are often encountered in actual operation. The shapes of the substrate materials vary, and sometimes it is difficult to obtain the blanks, which makes it difficult to directly use the substrate material to make cylindrical test rods for testing. At the same time, the bonding of cylindrical test rods to each other has high requirements for coaxiality. If the two test rods cannot be coaxial, the test results of the film bonding strength may deviate from the actual situation, thereby affecting the accurate evaluation of the film bonding performance. Summary of the invention

[0004] Purpose of the invention: The purpose of the present invention is to solve the deficiencies in the prior art and to provide a simple method for preparing a sample for testing the adhesion of a film layer and its application.

[0005] A simple film layer bonding strength test sample preparation method includes a cylindrical test rod, a test piece and a fixing tool. The end of the cylindrical test rod is provided with a flat boss with a through hole, the flat boss is clamped in a flat clamp, the fixing tool includes a clamp, a sliding block and a guide rail, and the clamp is provided with a locking bolt and an end limit nut. The specific steps include: S1. The flat boss of the cylindrical test rod is inserted into the groove of the fixture. The same operation is performed on the other test rod. The locking bolt is rotated to squeeze the fixture inward to fix the cylindrical test rod. S2. The end surface of the cylindrical test rod is evenly coated with adhesive and bonded to the test piece, and the end surface of the other cylindrical test rod is also evenly coated with adhesive; S3. Push the sliding block to prevent the end surface of the cylindrical test rod and the test piece from sticking to each other; S4. Tighten the end limit nut to maintain the extrusion force between the end face of the cylindrical test rod and the test piece; S5. According to the technical parameters of the adhesive, remove the adhesive after it is completely cured and reaches the maximum strength, install the test rod-test piece-test rod combination sample on the testing machine and perform a tensile test to obtain the bonding strength between the film layer and the base material.

[0006] A further improvement of the present invention is that the length of the flat boss is ≥30 mm, and the thickness of the flat boss is ≥5 mm.

[0007] A further improvement of the present invention is that a film layer is prepared on one side or both sides of the test piece.

[0008] A further improvement of the present invention is that the test piece is cut directly from the part, the area of ​​the test piece to be measured needs to cover the cross section of the cylindrical test rod, and the thickness of the test piece is ≥2mm.

[0009] A further improvement of the present invention is that in step S2, the bonding strength of the adhesive is not less than 70 MPa, and the curing time is not less than 24 hours.

[0010] A further improvement of the present invention is that the bonding and curing process is completed on a fixed fixture, the coaxiality tolerance of the cylindrical test rod is ≤0.3 mm, and the flatness tolerance of the end of the cylindrical test rod is ≤0.1 mm.

[0011] A further improvement of the present invention is that the cylindrical test rod is made of ductile iron QT400, the cross-sectional diameter is 20 mm, and the end surface roughness of the cylindrical test rod is ≥ Ra1.0 μm.

[0012] A sample obtained by a simple film adhesion test sample preparation method is used in a film adhesion test. The through hole of the flat boss is processed by milling and drilling. The through hole of the flat boss is installed with a positioning pin or a bolt, and the cylindrical surface of the cylindrical test rod is clamped in a V-clamp.

[0013] Compared with the prior art, the present invention provides a simple film layer bonding strength test sample preparation method and application, which achieves at least the following beneficial effects: The present invention discloses a simple sample preparation method and application for film layer adhesion test, which solves the problem that the film layer needs to be prepared on the surface of a cylindrical test rod during the film layer adhesion test, and the test rod material and the substrate material cannot be unified. By preparing a film layer on the surface of a test piece or directly cutting a test piece from a part, and using a fixed tool, the coaxiality tolerance of the test rod-test rod ≤0.3mm and the flatness of the end of the test rod ≤0.1mm can be achieved, and the film layer preparation process on the test rod surface can be eliminated. The test piece or the original sample can be flexibly used for sample preparation, and the test rod-test piece-test rod combination sample can be used for film layer adhesion test. The cylindrical test rod can be applied to a tensile testing machine with various types of fixtures. The operation method of the present invention is quick and convenient, and the tooling structure is compact. It has good applicability for testing the adhesion between the film layer and the substrate material. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is the structural diagram of the cylindrical test rod; Figure 2 This is the state diagram after the cylindrical test rod and the test piece are bonded; Figure 3 It is a three-dimensional structural diagram of the present invention; Figure 4 It is a front view of the present invention; Figure 5 It is a top view of the present invention.

[0015] In the figure: 1. clamp; 2. sliding block; 3. guide rail; 4. cylindrical test rod; 1-1. locking bolt; 1-2. end limit nut. DETAILED DESCRIPTION

[0016] Various exemplary embodiments of the present invention are now described in detail. It should be noted that unless otherwise specifically stated, the relative arrangement of the components and steps, numerical expressions and numerical values ​​described in these embodiments do not limit the scope of the present invention. The following description of at least one exemplary embodiment is actually only illustrative and is not intended to be any limitation on the present invention and its application or use.

[0017] The techniques, methods and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the techniques, methods and devices should be considered as part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0018] See the instruction manual Figure 1-5 A simple film layer bonding strength test sample preparation method and application, including a cylindrical test rod 4, a test piece and a fixing tool, the end of the cylindrical test rod 4 is provided with a flat boss with a through hole, the flat boss is clamped in a flat clamp, the fixing tool includes a clamp 1, a sliding block 2 and a guide rail 3, the clamp 1 is provided with a locking bolt 1-1 and an end limit nut 1-2, and the specific steps include: S1. The flat boss of the cylindrical test rod 4 is inserted into the groove of the fixture 1. The other test rod performs the same operation, and the locking bolt 1-1 is rotated so that the fixture 1 is squeezed inward to fix the cylindrical test rod 4; S2. The end surface of the cylindrical test rod 4 is evenly coated with adhesive and bonded to the test piece, and the end surface of the other cylindrical test rod is also evenly coated with adhesive; S3 pushes the sliding block 2 to prevent the end surface of the cylindrical test rod 4 and the test piece from sticking to each other; S4. Tighten the end limit nut 1-2 to maintain the extrusion force between the end surface of the cylindrical test rod 4 and the test piece; S5. According to the technical parameters of the adhesive, remove the adhesive after it is completely cured and reaches the maximum strength, install the test rod-test piece-test rod combination sample on the testing machine and perform a tensile test to obtain the bonding strength between the film layer and the base material.

[0019] The length of the flat boss is ≥30mm, and the thickness of the flat boss is ≥5mm; the test piece is prepared with a film layer on one side or both sides; the test piece is cut directly from the part, the area of ​​the test piece to be measured must cover the cross-section of the cylindrical test rod, and the thickness of the test piece is ≥2mm; in step S2, the bonding strength of the adhesive is not less than 70MPa, and the curing time is not less than 24h; the bonding and curing process is completed on a fixed fixture, the coaxiality tolerance of the cylindrical test rod 4 is ≤0.3mm, and the flatness tolerance of the end of the cylindrical test rod 4 is ≤0.1mm; the material of the cylindrical test rod 4 is ductile iron QT400 and higher grades, the cross-sectional diameter is 20mm, the end face roughness of the cylindrical test rod 4 is ≥Ra1.0μm, and the roughness of other positions is not required.

[0020] The invention discloses an application of a sample obtained by a simple sample preparation method for a membrane layer adhesion test in a membrane layer adhesion test. The through hole of a flat boss is processed by milling and drilling. A positioning pin or bolt is installed in the through hole of the flat boss. The cylindrical surface of a cylindrical test rod is clamped in a V-shaped clamp. The hole cooperates with the positioning pin, bolt or steel ball to achieve installation cooperation with a special clamp. Free adjustment with the clamp of a tensile testing machine can be achieved to avoid the influence of torsional force and shear force caused by poor clamping on the test result. The boss structure is combined with the cylindrical test rod and is suitable for a variety of clamping methods.

[0021] In summary, the present invention provides a simple film layer adhesion test sample preparation method and application. By using fixed tooling, a cylindrical test rod and a test piece, the test sample can be quickly prepared, the test rod surface film preparation process is eliminated, the test piece or the original sample is flexibly used for sample preparation, and the test rod-test piece-test rod combination sample is used for film layer adhesion test. The cylindrical test rod can be applied to tensile testing machines with various types of clamps. The operating method of the present invention is quick and convenient, the tooling structure is compact, and it has good applicability for testing the adhesion between the film layer and the substrate material.

[0022] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

Claims

1. A simple method for preparing samples for testing film adhesion, characterized in that: The invention comprises a cylindrical test rod (4), a test piece and a fixing tool, wherein a flat boss with a through hole is provided at the end of the cylindrical test rod (4), and the flat boss is clamped in a flat clamp, and the fixing tool comprises a clamp (1), a sliding block (2) and a guide rail (3), and the clamp (1) is provided with a locking bolt (1-1) and an end limit nut (1-2). The specific steps include: S1. The flat boss of the cylindrical test rod (4) is inserted into the groove of the fixture (1), and the other test rod performs the same operation, rotating the locking bolt (1-1) so that the fixture (1) is pressed inward to fix the cylindrical test rod (4); S2. The end surface of the cylindrical test rod (4) is evenly coated with adhesive and bonded to the test piece, and the end surface of the other cylindrical test rod is also evenly coated with adhesive; S3. Push the sliding block (2) to prevent the end surface of the cylindrical test rod (4) and the test piece from sticking to each other; S4. Tighten the end limit nut (1-2) to maintain the extrusion force between the end face of the cylindrical test rod (4) and the test piece; S5. According to the technical parameters of the adhesive, remove the adhesive after it is completely cured and reaches the maximum strength, install the test rod-test piece-test rod combination sample on the testing machine and perform a tensile test to obtain the bonding strength between the film layer and the base material.

2. A simple film bonding strength test sample preparation method according to claim 1, characterized in that: The length of the flat boss is ≥30 mm, and the thickness of the flat boss is ≥5 mm.

3. A simple film bonding strength test sample preparation method according to claim 1, characterized in that: The test piece is prepared with a film layer on one side or both sides.

4. A simple method for preparing samples for testing film adhesion according to claim 1, characterized in that: The test piece is cut directly from the part, the area of ​​the test piece to be measured needs to cover the cross section of the cylindrical test rod, and the thickness of the test piece is ≥2mm.

5. The method for preparing a simple film bonding strength test sample according to claim 1, characterized in that: In step S2, the bonding strength of the adhesive is not less than 70 MPa, and the curing time is not less than 24 hours.

6. A simple method for preparing samples for film adhesion test according to claim 1, characterized in that: The bonding and curing process is completed on the fixing fixture, the coaxiality tolerance of the cylindrical test rod (4) is ≤0.3 mm, and the flatness tolerance of the end of the cylindrical test rod (4) is ≤0.1 mm.

7. A simple method for preparing samples for testing film adhesion according to claim 1, characterized in that: The cylindrical test rod (4) is made of ductile iron QT400, has a cross-sectional diameter of 20 mm, and has an end surface roughness of ≥ Ra 1.0 μm.

8. An application of a sample obtained by the preparation method according to any one of claims 1 to 7 in a film bonding strength test, characterized in that: The through hole of the flat boss is processed by milling and drilling, and a positioning pin or a bolt is installed in the through hole of the flat boss. The cylindrical surface of the cylindrical test rod (4) is clamped in a V-shaped clamp.

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