Metallographic display method for silicon carbide electrode

Abstract

The present application relates to the technical field of silicon carbide electrode, and particularly relates to a metallographic display method of silicon carbide electrode, which comprises the following steps: S1, providing a silicon carbide electrode, and cutting a sample from the silicon carbide electrode along the radial direction of the silicon carbide electrode, wherein both ends of the sample are cutting surfaces, and the cutting surfaces are perpendicular to the silicon carbide electrode; S2, solidifying the sample by adopting a metallographic cold inlaying method; S3, taking one of the cutting surfaces of the sample as a processing surface, and sequentially performing rough grinding, fine grinding and mirror polishing on the processing surface; and S4, performing etching treatment on the processing surface after the grinding and polishing treatment in step S3, so as to form a metallographic display surface. Through the method provided in the present application, the sample can be processed to form a metallographic display surface on the sample, and then the metallographic microscope can be used to observe the organizational structure of the sample section.

Description

Technical Field

[0001] This invention relates to the field of silicon carbide electrode technology, and more specifically to a metallographic display method for silicon carbide electrodes. Background Technology

[0002] Silicon carbide electrodes are a new type of material sintered from silicon carbide. They have advantages such as high temperature resistance, voltage resistance, and electromagnetic interference resistance, and can work stably under high pressure and high temperature environments. In semiconductor etching processes, compared with silicon electrodes, silicon carbide electrodes have lower leakage current, higher voltage resistance, and higher electron mobility at high temperatures. They are now widely used in etching equipment. During use, silicon carbide electrodes may experience open circuit phenomena, with a sharp increase in resistance at some locations, leading to functional failure. As is well known, the internal structure of a material is directly and closely related to its physical properties such as hardness, resistivity, and strength. Metallographic observation is the most convenient and effective way to characterize the physicochemical state of the internal structure of a material.

[0003] Metallographic display is a technique commonly used to observe the internal structure of metals and their alloys. Silicon carbide electrodes are a new type of ceramic material, and conventional observation methods cannot obtain effective observation results. Therefore, it is necessary to develop a metallographic display method for silicon carbide. Summary of the Invention

[0004] In order to solve at least one of the technical problems mentioned in the background art, the present invention aims to provide a metallographic display method for silicon carbide electrodes.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A metallographic display method for a silicon carbide electrode includes the following steps:

[0007] S1. A silicon carbide electrode is provided, and a sample is cut from the silicon carbide electrode along the radial direction of the silicon carbide electrode. The two ends of the sample are cutting surfaces, and the cutting surfaces are perpendicular to the silicon carbide electrode.

[0008] S2. The sample is solidified using a metallographic cold mounting method;

[0009] S3. Take one of the cut surfaces of the sample as the treatment surface, and perform rough grinding, fine grinding and mirror polishing on the treatment surface in sequence.

[0010] S4. The surface treated by grinding and polishing in step S3 is etched to form a metallographic display surface.

[0011] Compared with existing technologies, the advantages of this solution are:

[0012] By processing the sample using the method provided in this solution, a metallographic display surface can be formed on the sample. Subsequently, with the help of a metallographic microscope, the microstructure of the sample cross section (i.e., the metallographic display surface) can be observed.

[0013] Furthermore, by using the cutting method provided in step S1, it can be ensured that the cutting surface is facing the center of the silicon carbide electrode and perpendicular to the silicon carbide electrode. In this way, as long as multiple samples are cut on the silicon carbide electrode in the same way, it can be ensured that the size and shape of the cutting surface of each sample are basically similar, which makes it convenient to perform the same metallographic treatment on each sample for comparison.

[0014] Preferably, in step S3, after the sample is clamped in the clamping plate, an automatic grinding machine is used to perform coarse grinding, fine grinding, and mirror polishing on the surface in sequence.

[0015] Preferably, the surface to be treated is coarsely ground using an automatic grinding machine, including: the automatic grinding machine uses a diamond grinding disc for coarse grinding, the rotation speed of the clamping disc is 150 r / min, and the rotation speed of the diamond grinding disc is 300 r / min; the rotation direction of the clamping disc and the grinding disc is the same, and the coarse grinding time is 2 min-3 min.

[0016] Preferably, the surface to be treated is finely ground using an automatic grinding machine, including: the automatic grinding machine uses a composite disc for fine grinding, the rotation speed of the clamping disc is 50 r / min, the rotation speed of the grinding disc is 200 r / min, the rotation direction of the clamping disc and the grinding disc is the same, and the fine grinding time is 10 min-15 min.

[0017] Preferably, the surface to be treated is mirror polished using an automatic grinding machine, including: using a porous neoprene polishing cloth as a grinding disc for mirror polishing; wherein the rotation speed of the clamping disc is 50 r / min, the rotation speed of the grinding disc is 150 r / min, and the rotation directions of the grinding disc and the clamping disc are opposite.

[0018] Preferably, deionized water is used as the grinding fluid during rough grinding; and / or a 3μm diamond suspension is used as the grinding fluid during fine grinding; and / or a 0.09μm alumina polishing fluid is used during mirror polishing.

[0019] Preferably, in step S4, a mixture of sodium hydroxide and hydrogen peroxide is used for corrosion.

[0020] Preferably, in step S1, the silicon carbide electrode is cut by water jet cutting to obtain the sample, wherein the water jet is parallel to the axial direction of the silicon carbide electrode and cuts along the radial direction of the silicon carbide electrode.

[0021] Preferably, in step S2, the sample is cured with epoxy resin.

[0022] Other advantages and effects of the present invention will be specifically explained in the detailed description and accompanying drawings. Attached Figure Description

[0023] Figure 1 These are the implementation steps of the present invention;

[0024] Figure 2 This is a schematic diagram of the structure after the sample is cut out from the silicon carbide electrode in this invention.

[0025] Figure 3 This is a schematic diagram of the silicon carbide electrode of the present invention. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be explained and described below with reference to the accompanying drawings. However, the following embodiments are only preferred embodiments of the present invention and not all of them. Other embodiments obtained by those skilled in the art based on the embodiments in the implementation methods without creative effort are all within the protection scope of the present invention.

[0027] In the following description, terms such as “inner,” “outer,” “upper,” “lower,” “left,” and “right” that indicate orientation or positional relationship are used only for the convenience of describing the embodiments and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0028] Please see Figure 1-3 As shown, this embodiment provides a metallographic display method for silicon carbide electrodes. To facilitate understanding of this embodiment, the structure of the silicon carbide electrode will be briefly described first:

[0029] like Figure 2 As shown, in this embodiment, the silicon carbide electrode 1 is generally circular, with an inner ring 11 formed by radially protruding inward from the bottom of its inner ring peripheral wall. The inner ring 11 and the inner ring peripheral wall of the silicon carbide electrode 1 are connected by an inclined wall 12.

[0030] Based on this, the metallographic display method for silicon carbide electrodes provided in this embodiment specifically includes the following steps:

[0031] S1. Sample Preparation: A silicon carbide electrode is provided. The specific structure of the silicon carbide electrode has been described above, so it will not be repeated here. A portion is cut from the silicon carbide electrode to serve as a sample of the silicon carbide electrode. The sample can be referenced from... Figure 2 and Figure 3 As shown in section M, specifically:

[0032] A sample is obtained by cutting along the radial direction of the silicon carbide electrode, with both ends of the sample being cut surfaces. The cut surfaces can be referenced... Figure 2 and Figure 3 As shown in M1, the cutting surface is perpendicular to the silicon carbide electrode. Here, the cutting surface being perpendicular to the silicon carbide electrode can also be understood as the cutting surface being perpendicular to the top surface of the silicon carbide electrode.

[0033] The specific cutting steps can be as follows: use a high-pressure water jet device to cut the silicon carbide electrode. This is equivalent to water cutting. Compared with mechanical blade cutting, water cutting can reduce the generation of burrs.

[0034] During the cutting process, the water jet is parallel to the axial direction of the silicon carbide electrode (or the water jet is perpendicular to the top surface of the silicon carbide electrode) and cuts along the radial direction of the silicon carbide electrode. In other words, the movement path of the water jet (i.e. the cutting path) is along the radial direction of the silicon carbide electrode.

[0035] By making two cuts on the silicon carbide electrode as described above, a sample can be obtained. The two ends of the sample are the cut surfaces formed by the cuts.

[0036] Samples cut along this path, such as Figure 3 As shown, the two cut surfaces M1 are oriented towards the center O of the silicon carbide electrode and are perpendicular to the silicon carbide electrode. Thus, the shapes and sizes of the cut surfaces at both ends of the sample are basically similar. Subsequently, one of the cut surfaces can be arbitrarily selected as the processing surface for subsequent metallographic processing.

[0037] Moreover, sometimes it may be necessary to cut multiple samples from the same silicon carbide electrode and then perform the same metallographic treatment on the multiple samples for comparison. In order to make the comparison results more reliable, the size and shape of the cut surfaces of each sample (specifically the cut surfaces that will be metallographically treated later) should be as similar as possible.

[0038] Therefore, as long as the above cutting method is followed, it can be guaranteed that the cut surfaces of each sample are similar.

[0039] S2. The sample is cured using a metallographic cold mounting method. Specifically, the cleaned sample is placed in a mold and cured with epoxy resin, wherein the mass ratio of epoxy resin to curing agent is 25:3.

[0040] The purpose of curing the sample is that when the sample is subjected to rough grinding, fine grinding and mirror polishing, a clamping plate is needed to clamp and fix the sample. However, the shape and size of the sample itself cannot be adapted to the clamping plate. Therefore, in this embodiment, epoxy resin is used in conjunction with a mold to cure the sample so that the overall shape of the cured sample can be clamped by the clamping plate.

[0041] S3. After the sample is cured, one of the cut surfaces of the sample is used as the treatment surface, and the treatment surface is subjected to rough grinding, fine grinding and mirror polishing in sequence.

[0042] The reason for choosing the cut surface of the sample as the processing surface in this embodiment is that, in this embodiment, the cut surface is equivalent to the axial section of the silicon carbide electrode, which can expose the internal structure of the inner ring, inclined wall and other parts of the silicon carbide electrode. In this way, the metallographic display surface formed later can fully display the internal structure of the silicon carbide electrode.

[0043] In step S3, it is preferable to use an automatic grinding machine to perform coarse grinding, fine grinding and mirror polishing on the surface in sequence. During the coarse grinding, fine grinding and mirror polishing process, the sample needs to be clamped on the clamping plate of the automatic grinding machine.

[0044] The rough grinding step is as follows:

[0045] The automatic grinding machine uses a 300mm diameter diamond grinding disc for coarse grinding, with a surface finish comparable to 120-mesh SiC paper. Furthermore, the diamond grinding disc is magnetically mounted on the grinding table of the automatic grinding machine for coarse grinding of the samples.

[0046] During the rough grinding process, the rotation speed of the clamping disc is 150 r / min, and the rotation speed of the diamond grinding disc is 300 r / min; the clamping disc and the grinding disc rotate in the same direction. Specifically, in this embodiment, both the clamping disc and the grinding disc rotate counterclockwise; the rough grinding time is 2 min-3 min.

[0047] In addition, deionized water is used as the grinding fluid during the rough grinding process. Deionized water mainly plays a role in lubrication and cooling during the rough grinding process.

[0048] The fine grinding steps are as follows:

[0049] Replace the diamond grinding disc used for coarse grinding with a composite disc of 300mm diameter and diamond single-step fine grinding hardness > HV40 for fine grinding. Install the composite disc on the grinding table of the automatic grinding machine by magnetic attraction to perform fine grinding on the sample.

[0050] During the fine grinding process, the rotation speed of the clamping disc is 50 r / min, and the rotation speed of the grinding disc is 200 r / min. The clamping disc and the grinding disc rotate in the same direction, both counterclockwise. The fine grinding time is 10 min to 15 min.

[0051] In addition, during the fine grinding process, a 3μm diamond suspension is used as the grinding fluid. At this time, the grinding fluid not only plays a role in lubrication and cooling, but the diamond particles in the grinding fluid can also improve the grinding accuracy.

[0052] The mirror polishing steps are as follows:

[0053] Replace the finely ground composite disc with a 300mm diameter porous neoprene polishing cloth as the grinding disc for mirror polishing; the porous neoprene polishing cloth is also magnetically mounted on the grinding table of the automatic grinding machine.

[0054] During mirror polishing, the chuck rotates at 50 r / min and the grinding disc rotates at 150 r / min. The grinding disc and the chuck rotate in opposite directions. Specifically, the chuck rotates clockwise and the grinding disc rotates counterclockwise. The polishing time is 10-15 minutes.

[0055] In addition, 0.09μm alumina polishing slurry was selected as the polishing slurry during the mirror polishing process.

[0056] After completing the rough grinding, fine grinding, and mirror polishing processes in step S3, proceed to step S4:

[0057] S4. The surface treated by grinding and polishing in step S3 is subjected to etching to form a metallographic display surface. Specifically:

[0058] After completing the mirror polishing of the sample, the polished sample was first ultrasonically cleaned with a mixture of deionized water and ethanol and then dried. The purpose of adding ethanol is to remove oil stains.

[0059] Next, the treated surface was etched with a mixture of sodium hydroxide and hydrogen peroxide for 45-60 minutes at a temperature of 45°C.

[0060] S5. After etching, the sample is ultrasonically cleaned and dried. Then, a metallographic microscope can be used to observe the metallographic display surface, thereby observing the microstructure of the sample cross-section.

[0061] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

Claims

1. A metallographic display method for a silicon carbide electrode, characterized in that, The silicon carbide electrode is annular, with an inner ring formed by a radially inward protrusion at the bottom of its inner peripheral wall. The space between the inner ring and the inner peripheral wall of the silicon carbide electrode is an inclined wall. The method includes the following steps: S1. A silicon carbide electrode is provided, and a sample is obtained by cutting along the radial direction of the silicon carbide electrode using water jet cutting, wherein the water jet of water jet cutting is parallel to the axial direction of the silicon carbide electrode, and the cutting surface is perpendicular to the silicon carbide electrode. S2. The sample is cured using a metallographic cold mounting method, in which epoxy resin is used to cure the sample; S3. Using one of the cut surfaces of the sample as the treatment surface, an automatic grinding machine is used to perform coarse grinding, fine grinding, and mirror polishing on the treatment surface in sequence: Rough grinding: A diamond grinding disc is used for rough grinding. The rotation speed of the clamping disc is 150 r / min, and the rotation speed of the diamond grinding disc is 300 r / min. The rotation directions of the clamping disc and the grinding disc are the same. The duration of the rough grinding is 2 min-3 min. Fine grinding: A composite disc is used for fine grinding. The rotation speed of the clamping disc is 50 r / min, and the rotation speed of the grinding disc is 200 r / min. The rotation directions of the clamping disc and the grinding disc are the same. The fine grinding time is 10 min-15 min. Mirror polishing: A porous neoprene polishing cloth is used as the grinding disc for mirror polishing; wherein, the rotation speed of the clamping disc is 50 r / min, the rotation speed of the grinding disc is 150 r / min, and the rotation directions of the grinding disc and the clamping disc are opposite. S4. The surface treated by grinding and polishing in step S3 is subjected to etching treatment to form a metallographic display surface. In step S4, a mixture of sodium hydroxide and hydrogen peroxide is used for etching. The etching time is 45 min-60 min and the temperature is 45℃.

2. The metallographic display method for a silicon carbide electrode according to claim 1, characterized in that, For rough grinding, deionized water is used as the grinding fluid; and / or for fine grinding, a 3μm diamond suspension is used as the grinding fluid; and / or for mirror polishing, a 0.09μm alumina polishing fluid is used.

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