Coating bonding strength testing method and sample brushing device

Abstract

This invention provides a method for testing coating adhesion strength and a sample brushing device. The method includes: driving a wheel-type brush to rotate around its axis, and using the rotating brush to brush the coated area of ​​the sample; obtaining the wear condition of the sample, and determining the coating adhesion strength based on the wear condition. The sample brushing device includes a mounting base, a wheel-type brush, and a first driving mechanism. The mounting base accommodates the sample; the wheel-type brush includes a brush shaft, bristles, and abrasive grains, with the bristles connected to the outer circumferential surface of the brush shaft and the abrasive grains connected to the outer surface of the bristles. The first driving mechanism drives the wheel-type brush to rotate around its axis. This coating adhesion strength testing method can effectively simulate coating failure during actual cutting, and the coating adhesion strength measured by this method can accurately reflect the actual adhesion strength of the coating on the cutting tool.

Description

Technical Field

[0001] This invention relates to the field of coating testing technology, and in particular to a method for testing coating bonding strength and a sample brushing device. Background Technology

[0002] Diamond coatings possess high hardness and wear resistance, along with a low coefficient of friction. Diamond-coated tools are commonly used for machining difficult-to-machine materials such as graphite, high-silicon aluminum, titanium alloys, and carbon fiber. A typical diamond-coated tool consists of a substrate and a diamond coating applied to the substrate surface. The bonding strength between the diamond coating and the substrate is related to the tool's cutting performance and tool life; generally, higher bonding strength results in better cutting stability and tool life. To study the performance of diamond-coated tools, it is necessary to test the bonding strength between the diamond coating and the substrate.

[0003] Existing methods for testing the bond strength between coatings and substrates include tensile testing, bubbling testing, indentation / scratch testing, tribological testing, and erosion testing. These methods require preparing a sample covered with the coating, then attempting to cause some damage to the coating, and evaluating the bond strength between the coating and the substrate based on the damage effect.

[0004] However, existing methods for testing coating adhesion strength cannot simulate the load conditions of the tool coating during actual cutting, nor can they simulate coating failure during actual cutting. This means that the coating adhesion strength measured during the test process cannot accurately reflect the actual coating adhesion strength of the tool, nor can it accurately reflect the tool's performance during actual cutting. Summary of the Invention

[0005] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention proposes a coating adhesion strength testing method, which can well simulate the failure of the coating during actual cutting by the tool. The coating adhesion strength measured by this testing method can well reflect the actual adhesion strength of the coating on the tool.

[0006] The present invention also proposes a sample brushing device.

[0007] A coating adhesion strength testing method according to a first aspect of the present invention includes:

[0008] A drive wheel brush rotates around the axis of the brush shaft, and the rotating wheel brush is used to brush and polish the coated area of ​​the sample; wherein, the wheel brush includes a brush shaft, bristles and abrasive grains, the bristles are connected to the outer peripheral surface of the brush shaft and protrude radially along the brush shaft, and the abrasive grains are connected to the outer surface of the bristles.

[0009] The wear condition of the sample is obtained, and the bonding strength of the coating is determined based on the wear condition.

[0010] The coating adhesion strength testing method according to the first aspect of the present invention has at least the following beneficial effects: when the wheel-type brush polishes the sample, the movement of the wheel-type brush relative to the sample is similar to the movement of the workpiece relative to the cutting tool. Accordingly, the load condition of the coating on the sample during the polishing process by the wheel-type brush is highly similar to the load condition of the coating on the cutting tool when it comes into contact with the workpiece. Therefore, the coating adhesion strength testing method of the present invention can well simulate the wear and failure of the coating on the cutting tool during the actual use of the cutting tool, and the coating adhesion strength of the sample measured by this testing method can well reflect the actual adhesion strength of the coating on the cutting tool.

[0011] According to some embodiments of the present invention, the sample includes a front face and a rear face, both of which are provided with a coating, and the front face and the rear face intersect to form an edge; the step of brushing the coated area of ​​the sample with the rotating wheel brush includes: brushing the edge with the wheel brush.

[0012] According to some embodiments of the present invention, obtaining the wear condition of the sample includes: obtaining the dimensional parameters of the wear area of ​​the sample.

[0013] According to some embodiments of the present invention, obtaining the dimensional parameters of the wear region of the sample includes obtaining the length of the wear region and obtaining the width of the wear region.

[0014] According to some embodiments of the present invention, obtaining the size parameters of the wear area of ​​the sample includes: acquiring an image of the wear area using a visual inspection device and obtaining the size parameters.

[0015] According to a second aspect of the present invention, a sample brushing apparatus includes: a mounting base for accommodating a sample with a coating on its surface; a wheel-type brush including a brush shaft, bristles, and abrasive grains, wherein the bristles are connected to the outer peripheral surface of the brush shaft and protrude radially along the brush shaft, the abrasive grains are connected to the outer surface of the bristles, and one end of the bristles away from the brush shaft is used to contact the surface of the sample; and a first driving mechanism connected to the brush shaft, the first driving mechanism being used to drive the wheel-type brush to rotate about the axis of the brush shaft.

[0016] The sample brushing apparatus according to the second aspect of the present invention has at least the following beneficial effects: the apparatus can assist in realizing the above-mentioned coating bonding strength testing method and improve the convenience of brushing the sample.

[0017] According to some embodiments of the present invention, the sample brushing device further includes a second driving mechanism, wherein the first driving mechanism or the mounting base is connected to the second driving mechanism, and the second driving mechanism is used to drive the wheel brush and the mounting base to move closer to or further away from each other along the radial direction of the brush axis.

[0018] According to some embodiments of the present invention, the mounting base is connected to the second drive mechanism, and the mounting base includes two clamping blocks that can move closer to or further away from each other, the two clamping blocks being able to jointly clamp a portion of the sample.

[0019] According to some embodiments of the present invention, the abrasive grains are made of diamond, silicon carbide or corundum.

[0020] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0022] Figure 1 This is a schematic diagram of the coating adhesion strength testing method of the present invention;

[0023] Figure 2 This is a schematic diagram of a machining method in the prior art where a cutting tool processes a workpiece;

[0024] Figure 3 This is a schematic diagram of the sample brushing device brushing a sample in one embodiment of the present invention.

[0025] Figure 4 for Figure 3 A schematic diagram of bristles and abrasive grains in a wheel-type brush;

[0026] Figure 5 for Figure 3 A schematic diagram (top view) of a sample being brushed by a medium-sized brush.

[0027] Figure 6 This is a schematic diagram of a sample in one embodiment of the present invention;

[0028] Figure 7 This is a schematic diagram of one type of wear condition of the sample in this invention;

[0029] Figure 8 This is a schematic diagram illustrating another wear condition of the sample in this invention;

[0030] Figure 9 This is a schematic diagram of the brushing depth of a wheel-type brush.

[0031] Reference numerals: 101-workpiece, 102-tool, 103-first drive mechanism, 104-wheel brush, 105-brush shaft, 106-brush bristles, 107-sample, 108-mounting base, 109-abrasive grain, 110-brushing section, 111-mounting section, 112-flank face, 113-rake face, 114-edge, 115-wear area. Detailed Implementation

[0032] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0033] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0034] In the description of this invention, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0035] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0036] The coating adhesion strength directly measured by the detection method of this invention refers to the adhesion strength between the coating and the substrate of the sample. It should be noted that the coating adhesion strength detection method of this invention can be used to detect the adhesion strength of diamond coatings, as well as the adhesion strength of other types of coatings.

[0037] Reference Figure 1 This invention provides a method for testing coating adhesion strength, comprising the following steps:

[0038] S10: Drive the wheel brush 104 to rotate around the axis of the brush shaft 105, and use the rotating wheel brush 104 to brush the coated area of ​​the sample 107.

[0039] S20: Obtain the wear condition of sample 107 and determine the bonding strength of the coating based on the wear condition.

[0040] In this invention, "brushing" refers to polishing an object with a brush (e.g., polishing sample 107 with a wheel-type brush 104). See reference... Figure 3 The wheel-type brush 104 in the above-mentioned testing method includes a brush shaft 105, brush bristles 106, and abrasive grains 109. The brush bristles 106 are connected to the outer peripheral surface of the brush shaft 105 and protrude radially along the brush shaft 105. (Refer to...) Figure 4 Abrasive grains 109 are attached to the outer surface of bristles 106. Multiple bristles 106 are provided, and each bristle 106 has multiple abrasive grains 109. (Refer to...) Figure 3 In step S10 above, when the coated area of ​​sample 107 is brushed, the end of the brush bristles 106 away from the brush shaft 105 will contact sample 107, and the abrasive grains 109 on the brush bristles 106 will also contact sample 107. The hardness of the material of the abrasive grains 109 is greater than the hardness of the material of the brush bristles 106, and the abrasive grains 109 are the main cause of wear on the coating.

[0041] To facilitate the explanation of the effectiveness of the coating bonding strength testing method of the present invention, the tool 102 and the test specimen 107 used for testing are described below.

[0042] Figure 2 This illustrates how the cutting tool 102 processes the workpiece 101. Figure 2 This can be viewed as a view along the axis of workpiece 101. Workpiece 101 rotates around its own axis, and during the rotation of workpiece 101, tool 102 removes a portion of the material from workpiece 101, thereby performing cutting machining on workpiece 101.

[0043] The specimen 107 includes a specimen substrate and a coating, with at least a portion of the outer surface of the specimen substrate covered by the coating. Since the testing of the coating adhesion strength of the specimen 107 is for studying the performance of the tool 102, the coating in the specimen 107 can be the same as the coating of the tool 102, and the specimen substrate in the specimen 107 can be made of the same material as the substrate of the tool 102. For example, to study the performance of a diamond-coated tool, the coating of the specimen 107 is a diamond coating, and the specimen substrate is made of the same material as the substrate of the diamond-coated tool. Furthermore, the bonding process between the coating and the specimen substrate in the specimen 107 can be set to be the same as the bonding process between the coating and the substrate in the tool 102.

[0044] contrast Figure 2 and Figure 3When the wheel-type brush 104 brushes the sample 107, the movement of the wheel-type brush 104 relative to the sample 107 is similar to the movement of the workpiece 101 relative to the tool 102. Correspondingly, the load on the coating of the sample 107 during the brushing process is highly similar to the load on the coating of the tool 102 when it comes into contact with the workpiece 101. Therefore, the coating adhesion strength testing method of the present invention can well simulate the wear and failure of the coating on the tool 102 during actual use of the tool 102, and the coating adhesion strength of the sample 107 measured by this testing method can well reflect the actual adhesion strength of the coating on the tool 102.

[0045] In one embodiment, the coating of the sample 107 to be tested is a diamond coating, and correspondingly, the abrasive grains 109 can be made of diamond. The abrasive grains 109 made of diamond can effectively wear down the diamond coating, and the wear effect is quite significant. Therefore, when the abrasive grains 109 are made of diamond, the above-described testing method is suitable for testing the bonding strength of the diamond coating. The material of the bristles 106 can be nylon.

[0046] In some embodiments, if the coating in sample 107 is not a diamond coating but another type of coating, the abrasive grains 109 in the wheel brush 104 can still be set as diamond abrasive grains. Of course, depending on the specific type of coating, the material of the abrasive grains 109 can be adjusted to other materials that can effectively wear down the coating and produce a significant wear effect. For example, the abrasive grains 109 can be made of silicon carbide (SiC), or they can be made of corundum (Al2O3). The hardness of abrasive grains 109 made of silicon carbide or corundum is lower than that of abrasive grains 109 made of diamond. When the coating of the tool 102 is set to a coating with a lower hardness than a diamond coating, abrasive grains 109 with a lower hardness than diamond can be used. Furthermore, to obtain different wear effects, the mesh size or diameter of the abrasive grains 109 can also be adjusted.

[0047] like Figure 2 As shown, during the cutting process of the tool 102 on the workpiece 101, the main part of the tool 102 that is worn is the cutting edge. Compared with the parts of the tool 102 that do not contact the workpiece 101, the coating adhesion strength at the cutting edge has a greater impact on the performance and life of the tool 102. In order to make the coating adhesion strength measured by the detection method better reflect the coating adhesion strength at the cutting edge of the tool 102, in one embodiment, the above step S10 specifically includes: brushing the edge 114 with a wheel-type brush 104. Specifically, as Figure 5As shown, the sample 107 includes an edge cutting edge 114, which includes a rake face 113 and a flank face 112. Both the rake face 113 and the flank face 112 are coated. The rake face 113 and the flank face 112 intersect to form the edge cutting edge 114.

[0048] It should be noted that, referring to Figure 5 When the wheel-type brush 104 brushes the edge 114, the bristles 106 and the abrasive grains 109 on the bristles 106 will contact the edge formed by the intersection of the front face 113 and the rear face 112, as well as the ends of the front face 113 and the rear face 112. Figure 5 As shown, further, in order to make the measured coating bonding strength better reflect the coating bonding strength at the cutting edge of the tool 102, the angle between the back face 112 and the direction of brush movement is set to be the same as the tool back angle when the tool 102 is actually used, and the angle between the front face 113 and the brush 106 is set to be the same as the tool front angle when the tool 102 is actually used.

[0049] In some embodiments, step S20 of the coating adhesion strength testing method, obtaining the wear condition of the sample 107, may include: obtaining the dimensional parameters of the wear region 115 of the sample 107. This allows for the quantification of the degree of coating wear, facilitating the evaluation of coating adhesion strength.

[0050] The location of wear area 115 can be referenced. Figure 6 or Figure 7 The wear area 115 refers to the area in sample 107 where a coating was originally applied but has been removed. The sample substrate is directly exposed in the wear area 115. The dimensional parameters of the wear area 115 can be obtained automatically using a vision inspection device to automatically detect the coating adhesion strength. The vision inspection device acquires an image of the wear area 115, analyzes the image, identifies the wear area 115 based on the color difference between the wear area 115 and the non-patterned area, and then automatically calculates the dimensional parameters of the wear area 115. Alternatively, the dimensional parameters of the wear area 115 can also be obtained manually by measuring the wear area 115.

[0051] In one embodiment, obtaining the size parameter of the wear region 115 can be obtaining the area of ​​the wear region 115. In another embodiment, if the shape of the wear region 115 is irregular, obtaining the size parameter of the wear region 115 can also be obtaining the length L and width W of the wear region 115 (e.g., ...). Figure 6 As shown in the image, this would be relatively simpler.

[0052] After obtaining the dimensional parameters of the wear area 115, the bonding strength of the coating can be determined based on the numerical values ​​of these parameters. For example, if the length of the wear area 115 falls within the first interval and the width falls within the second interval, the coating bonding strength is of the first strength. If the length of the wear area 115 falls within the third interval and the width falls within the fourth interval, the coating bonding strength is of the second strength. In other words, the coating bonding strength varies depending on the dimensional parameters of the wear area 115. The terms "first strength" and "second strength" here can refer to numerical values ​​indicating the level of coating bonding strength, or to terms like "level one" and "level two" that differentiate bonding strength grades.

[0053] Furthermore, if it is necessary to compare the coating bonding strength of two samples 107, the dimensional parameters of the wear area 115 of the two samples 107 can be directly compared. For example, if the length and width of the wear area 115 of one sample 107 are both greater than the length and width of the wear area 115 of the other sample 107, then the coating bonding strength of the former sample 107 is lower.

[0054] The present invention also provides a sample brushing device, which can assist in realizing the above-mentioned coating bonding strength testing method and improve the convenience of brushing the sample 107.

[0055] Reference Figure 3 and Figure 4 The sample brushing device includes a mounting base 108, a wheel-type brush 104, and a first drive mechanism 103. The mounting base 108 accommodates a portion of the sample 107, with the portion of the sample 107 to be brushed protruding outside the mounting base 108. The wheel-type brush 104 includes a brush shaft 105, bristles 106, and abrasive grains 109. The bristles 106 are connected to the outer circumferential surface of the brush shaft 105 and protrude radially along the brush shaft 105. The abrasive grains 109 are connected to the outer surface of the bristles 106, and the end of the bristles 106 away from the brush shaft 105 is used to contact the sample 107. The first drive mechanism 103 is connected to the brush shaft 105 and drives the wheel-type brush 104 to rotate around the axis of the brush shaft 105. The first drive mechanism 103 may include a motor, which can be connected to the brush shaft 105 via a coupling or via a gear set, drive belt, or other transmission components. The motor drives the wheel brush 104 to rotate, thereby driving the wheel brush 104 to brush and polish the sample 107.

[0056] like Figure 8As shown, in one embodiment, the sample 107 may include a mounting section 111 and a brushing section 110, with the mounting section 111 located at one end of the sample 107. The brushing section 110 is the portion of the sample 107 that is brushed by the wheel-type brush 104. The brushing section 110 protrudes beyond the mounting base 108 and is coated. The mounting section 111 is used to connect to the mounting base 108. The mounting section 111 generally does not contact the wheel-type brush 104, and whether or not the mounting section 111 is coated is optional.

[0057] In some embodiments, the mounting base 108 may include a clamp comprising two clamping blocks (not shown) that are movable relative to each other, moving closer or further apart. When it is necessary to mount the sample 107 onto the mounting base 108, the two clamping blocks may clamp the sample 107 (e.g., clamping the mounting segment 111 of the sample 107); when it is necessary to remove the sample 107, the two clamping blocks may be moved apart, thereby releasing the sample 107. In other embodiments, the mounting base 108 may also be provided with a mounting groove or mounting hole, into which a portion of the sample 107 (e.g., the mounting segment 111) is inserted, thereby fixing the sample 107 relative to the mounting base 108.

[0058] In one embodiment, the sample brushing device further includes a second driving mechanism (not shown), which is connected to the first driving mechanism 103 or the mounting base 108. The second driving mechanism is used to drive the wheel-type brush 104 and the mounting base 108 to move closer or further apart along the radial direction of the brush shaft 105, thereby driving the wheel-type brush 104 and the sample 107 to move closer or further apart. The second driving mechanism can be configured as a linear module to... Figure 3 For example, the second drive mechanism can drive the mounting base 108 to move in the left and right directions.

[0059] Before the sample 107 is installed on the mounting base 108, the mounting base 108 and the wheel-type brush 104 are relatively far apart, making it convenient for the user to install the sample 107 onto the mounting base 108. After the sample 107 is installed in the mounting base 108, the second drive mechanism drives the wheel-type brush 104 and the sample 107 to move closer together until the wheel-type brush 104 contacts the sample 107. After brushing is completed, the second drive mechanism can drive the wheel-type brush 104 and the sample 107 to move away from each other, so that the user can remove the sample 107 from the mounting base 108. That is, the second drive mechanism facilitates the installation and removal of the sample 107.

[0060] Furthermore, the second drive mechanism facilitates the adjustment of the brushing depth of the wheel-type brush 104, thereby adjusting the brushing force and effect on the sample 107. The brushing depth can be adjusted using... Figure 9Let's understand this. If we denote the length of the bristles 106 as D1, the distance between the brush shaft 105 and the part of the sample 107 that contacts the bristles 106 when the wheel-type brush 104 brushes the sample 107 as D2, and the brushing depth as D3, then the brushing depth D3 satisfies: D3 = D1 - D2. It should be noted that D1, D2, and D3 are all radial dimensions of the brush shaft 105 (D1, D2, and D3 are not shown in the figure). The brushing depth is related to the brushing effect. Different brushing depths result in different interaction forces between the bristles 106 and the sample 107, and thus different brushing effects of the wheel-type brush 104 on the sample 107. A good brushing effect of the wheel-type brush 104 on the sample 107 means that the wheel-type brush 104 can cause significant wear on the sample 107 in a short time. With the second drive mechanism in place, the distance between the sample 107 and the wheel brush 104 can be controlled by controlling the operation of the second drive mechanism, thereby controlling the brushing depth and adjusting the brushing effect.

[0061] In the description of this invention, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

Claims

1. A method for testing the bonding strength of a coating, characterized in that, include: A drive wheel-type brush rotates around the axis of the brush shaft, and the rotating wheel-type brush is used to brush and polish the edge of the sample; wherein, the wheel-type brush includes a brush shaft, brush bristles and abrasive grains, the brush bristles are connected to the outer peripheral surface of the brush shaft and protrude radially along the brush shaft, the abrasive grains are connected to the outer surface of the brush bristles, the sample includes a front cutting face and a rear cutting face, both of which are provided with a coating, and the front cutting face and the rear cutting face intersect to form the edge; Obtain the dimensional parameters of the wear area of ​​the sample, and determine the bonding strength of the coating based on the dimensional parameters.

2. The coating adhesion strength testing method according to claim 1, characterized in that, The dimensional parameters for obtaining the wear area of ​​the sample include: obtaining the length of the wear area and obtaining the width of the wear area.

3. The coating adhesion strength testing method according to claim 1, characterized in that, The step of obtaining the size parameters of the wear area of ​​the sample includes: acquiring an image of the wear area using a visual inspection device and obtaining the size parameters.

4. A sample brushing and grinding device, characterized in that, include: Mounting base for accommodating a sample with a coating on its surface, the sample including a rake face and a flank face, both the rake face and the flank face being coated, the rake face and the flank face intersecting to form an edge; A wheel-type brush includes a brush shaft, bristles, and abrasive grains. The bristles are connected to the outer peripheral surface of the brush shaft and protrude radially along the brush shaft. The abrasive grains are connected to the outer surface of the bristles. One end of the bristles away from the brush shaft is used to contact the surface of the sample. A first driving mechanism is connected to the brush shaft. The first driving mechanism is used to drive the wheel brush to rotate around the axis of the brush shaft so that the wheel brush can brush the edge.

5. The sample brushing device according to claim 4, characterized in that, It also includes a second drive mechanism, wherein the first drive mechanism or the mounting base is connected to the second drive mechanism, and the second drive mechanism is used to drive the wheel brush and the mounting base to move closer to or further away from each other along the radial direction of the brush axis.

6. The sample brushing device according to claim 5, characterized in that, The mounting base is connected to the second drive mechanism. The mounting base includes two clamping blocks that can move closer to or further away from each other, and the two clamping blocks can jointly clamp a portion of the sample.

7. The sample brushing device according to claim 4, characterized in that, The abrasive grains are made of diamond, silicon carbide, or corundum.

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