A method for preparing a deep slit for measurement

Abstract

The present invention discloses a method for preparing a deep slit for measurement, comprising: step 1, preparing a coating layer with a micron-level thickness on the surface of a first plane and completely covering the first plane; step 2, closely fitting a second plane without a coating layer on the surface to the coating layer of the first plane, keeping the relative position of the second plane and the first plane unchanged, to form a sample; step 3, placing the sample in a solution, the solution can dissolve the coating layer but cannot dissolve the first plane and the second plane, and the solution completely immerses the first plane, the coating layer and the second plane at the same time; step 4, measuring the size of the deep slit by microscopic observation, if a sample does not meet the requirements, repeating steps 1 to 3 for multiple times, and selecting a deep slit sample of micron level that meets the depth requirements from multiple samples. The preparation process of the present invention is simple and easy, and the preparation cost is low.

Description

Technical Field

[0001] The invention belongs to the technical field of measurement, and in particular relates to a method for preparing a deep slit that can be used for accurate measurement. Background Art

[0002] In the field of aerospace engines, deep slits that can be accurately measured are required for the inspection of some parts. Existing processing methods are difficult to achieve micron-level deep slit processing, or the processing cost of deep slits is high, the equipment or process requirements are high, and the operation is difficult. Summary of the invention

[0003] In order to solve the above technical problems, the present invention aims to provide a method for preparing deep slits for measurement, which can prepare deep slits of micrometer level that meet the requirements on ordinary equipment, and the preparation process is simple and easy with low preparation cost.

[0004] The basic concept of the present invention is: by using two standard gauge blocks, and seamlessly embedding a micron-level coating between the plane surfaces of the two standard gauge blocks, and then fixing the two standard gauge blocks, and then using a solution to dissolve the coating between the standard gauge blocks, because the solution does not react with the standard gauge blocks, but only dissolves the coating, and finally forms a deep slit between the two standard gauge blocks. The present invention prepares a deep slit for precise measurement through the above method.

[0005] The present invention adopts the following technical solutions:

[0006] A method for preparing a deep slit for measurement, wherein the deep slit is at the micron level, comprising:

[0007] Step 1: prepare a coating layer with a micron-level thickness on the surface of the first plane and completely covering the first plane; the thickness of the coating layer is controlled as required;

[0008] Step 2: closely attaching a second plane without a coating layer on its surface to the coating layer on the first plane, keeping the relative positions of the second plane and the first plane unchanged, to form a sample;

[0009] Step 3, placing the sample in a solution, wherein the solution can dissolve the coating layer but cannot dissolve the first plane and the second plane, and the solution completely immerses the first plane, the coating layer and the second plane at the same time, and when the coating layer is dissolved, a deep slit is formed between the first plane and the second plane; deep slits of different depths can be obtained according to different dissolution times, and the longer the dissolution time, the deeper the deep slits, and the shorter the dissolution time, the shallower the deep slits;

[0010] Step 4: Measure the size of the deep slit by microscope observation. If a sample does not meet the requirements, repeat steps 1 to 3 multiple times to select a deep slit sample at the micron level that meets the depth requirements from multiple samples.

[0011] As an option,

[0012] In the step 1, a plane surface of the first standard gauge block is selected as the first plane;

[0013] In the step 2, a plane surface of the second standard gauge block is selected as the second plane.

[0014] Furthermore, the first standard gauge block and the second standard gauge block are completely identical.

[0015] Furthermore, in the step 1, a coating layer is prepared on all surfaces of the first standard gauge block including the first plane, wherein the coating layer thickness on at least the first plane is in the micrometer level.

[0016] As an option, in step 1, the coating layer is a silver coating layer, a copper coating layer, a zinc coating layer or a cadmium coating layer. Different coating layers are adjusted and selected according to the preparation cost, preparation difficulty, deep slit detection application object, etc.

[0017] As an option, in the step 1, the coating layer is formed by electroplating.

[0018] As an option, in the step 2, the first plane and the second plane are connected and fixed by welding to ensure that the relative position of the second plane and the first plane remains unchanged, thereby forming a sample.

[0019] As an option, in step 1, the coating layer is an electroplated silver layer, and the electroplating method comprises the following steps performed in sequence:

[0020] For hanging, use copper wire to clamp the first plane;

[0021] Degreasing: the first plane surface after degreasing can be completely covered by the water film;

[0022] Wash with hot water, wash the first surface with hot water;

[0023] Wash with cold water, clean the first surface with cold water;

[0024] Weak etching, using hydrochloric acid or sulfuric acid to etch the first plane;

[0025] Silver electroplating: performing silver electroplating on the surface of the first plane;

[0026] Wash with running cold water, use running cold water to rinse the silver-plated layer;

[0027] Disassembly and drying: disassembly of the first plane with the silver-plated layer and the copper wire, and then drying the first plane and the silver-plated layer.

[0028] Furthermore, in the silver electroplating step, the silver electroplating bath solution includes 20 to 30 g / L of silver, 45 to 80 g / L of potassium cyanide, and 15 to 50 g / L of potassium carbonate.

[0029] Furthermore, in the silver electroplating step, the current density during electroplating is 0.3 to 0.8 amperes per square decimeter, the electroplating temperature is 15 to 35 degrees Celsius, and the electroplating time is 20 to 40 minutes.

[0030] Compared with the prior art, the present invention can complete the preparation of micron-level deep slits on ordinary equipment (electroplating equipment and microscope), and has high preparation efficiency, small capital investment, low operating difficulty and easy implementation. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 These are two standard gauge blocks whose surfaces are not silver-plated;

[0032] Figure 2 Two standard gauge blocks are shown in the figure, one of which has its entire surface plated with silver, and the other has no surface plated with silver. Specifically, the standard gauge block on the left is not plated with silver, and the standard gauge block on the right is plated with silver and has slightly lost its metallic luster. DETAILED DESCRIPTION

[0033] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments, but it should not be understood that the scope of the subject matter described in the present invention is limited to the following embodiments. Without departing from the above-mentioned technical ideas of the present invention, various modifications, substitutions and changes made according to the common technical knowledge and customary means in the field are included in the scope of the present invention.

[0034] The basic principle of the present invention is to form a height difference through different solubility in the same direction, and the area size (thickness) perpendicular to the height difference direction is at the micron level, so the height difference finally formed is a deep slit at the micron level.

[0035] In order to prepare a micron-level deep slit for measurement, the preparation idea in this embodiment is as follows:

[0036] ① Select two standard gauge blocks and plate all outer surfaces of one of the two standard gauge blocks with silver (or copper, zinc, cadmium, etc.) for 5 microns.

[0037] ② Fit the working surfaces of the two standard gauge blocks (i.e. the surface with the coating layer of micron level thickness and the surface of the other standard gauge block without the coating layer) tightly.

[0038] ③ Fix the two ends of the two tightly fitting standard gauge blocks (i.e. the position perpendicular to the fitting surfaces of the two standard gauge blocks) by welding.

[0039] ④ Use solution (different coating materials should use corresponding solutions, and the solution can dissolve the coating layer) to chemically dissolve the coating layers in the two standard gauge blocks.

[0040] The two standard blocks can be completely identical or not. The basic principle is that the material of the two standard blocks is insoluble in the solution used to dissolve the coating layer. The reason for choosing standard blocks is that it is easy to prepare a uniform coating layer on the flat surface of the standard blocks. If it is a curved surface, it is not easy to control the thickness of the coating layer.

[0041] The surface-coated standard gauge blocks must be coated on at least one plane surface. Of course, in order to facilitate the observation of subsequent dissolution and facilitate the coating operation, it is preferred that all surfaces of the standard gauge blocks are coated. On the one hand, when all surfaces of the standard gauge blocks are coated, there is no need to take protective measures to protect and isolate the non-coated surfaces on the standard gauge blocks, which simplifies the coating process. On the other hand, when all surfaces of the standard gauge blocks are coated, the visual difference between the uncoated standard gauge blocks and the coated standard gauge blocks can be clearly observed with the naked eye during the process of the solution dissolving the coating layer, thereby assisting in judging the end time of the dissolution process. For example, when the appearance colors of the two standard gauge blocks tend to be consistent, it means that a deep slit is about to form.

[0042] In addition, it is preferred to select two completely identical standard gauge blocks in order to facilitate the alignment of the first plane and the second plane on the two standard gauge blocks so that the deep slit obtained after the final dissolution is on the same plane, which is convenient for later use. If the two standard gauge blocks are not completely aligned, the deep slit obtained after dissolution is on a step surface (the end face of the first standard gauge block is higher or lower than the end face of the second standard gauge block, forming a step surface).

[0043] like Figure 1-2 As shown, taking the silver plating between the two standard gauge blocks as an example, the implementation method is as follows. The wire drying that needs to be explained is: Figure 1 and Figure 2 The numbers on the surface of the standard gauge block only represent the specifications of the gauge block:

[0044] 1. Silver plating of standard gauge blocks:

[0045] 1.1 Installation:

[0046] Use copper wire with an outer diameter of (1-2) mm to clamp the standard gauge block to ensure that the sample does not shake and the middle part of the surface to be etched is not blocked;

[0047] 1.2 Wipe and remove oil:

[0048] Use flannel cloth dipped in decontamination powder, cleaning agent, etc. to wipe and remove oil from the standard gauge block to ensure that the surface of the sample is completely covered by the water film;

[0049] 1.3 Hot water washing:

[0050] Rinse with warm water (40-60) degrees Celsius;

[0051] 1.4 Cold water washing:

[0052] Rinse with running tap water;

[0053] 1.5 Weak etch:

[0054] Hydrochloric acid or sulfuric acid (100-150) g / L; room temperature; time (0.5-2) minutes;

[0055] 1.6 Cold water washing:

[0056] Rinse with running tap water;

[0057] 1.7 Silver plating:

[0058]

[0059]

[0060] Process parameters: current density (0.3-0.8) ampere / square decimeter; temperature (15-35) degrees Celsius; time: (20-40) minutes;

[0061] 1.8 Cold water washing:

[0062] Rinse with running tap water;

[0063] 1.9 Disassembly:

[0064] Remove the standard gauge block;

[0065] 1.10 Drying:

[0066] Blow dry with compressed air or hang dry;

[0067] 2. Fixed standard gauge block:

[0068] Fix the two ends of the two standard gauge blocks by welding (one of the two standard gauge blocks is silver-plated);

[0069] 3. Remove the silver coating from the standard gauge block:

[0070] Mix ammonia water and hydrogen peroxide in a ratio of 1:1, and then place the two standard blocks fixed at both ends into the mixed solution until the silver coating is completely dissolved;

[0071] 4. Select the standard gauge block that meets the slit requirements:

[0072] Observe with a microscope with a scale and select standard gauge block specimens with deep slits that meet the requirements.

[0073] The contents not described in detail in the specification of the present invention belong to the prior art known to the professional and technical personnel in the field. Although the illustrative specific embodiments of the present invention are described above to facilitate the understanding of the present invention by the technical personnel in the field, it should be clear that the present invention is not limited to the scope of the specific embodiments. For ordinary technicians in the field of this technology, as long as various changes are within the spirit and scope of the present invention defined and determined by the attached claims, these changes are obvious, and all inventions and creations using the concept of the present invention are protected.

Claims

1. A method for preparing a deep slit for measurement, wherein the deep slit is at the micron level, characterized in that: include, Step 1: select a plane surface of the first standard gauge block as the first plane, and prepare a coating layer on all surfaces of the first standard gauge block including the first plane, wherein at least the coating layer on the first plane has a thickness of micrometer level and completely covers the first plane; Step 2, selecting a plane surface of the second standard gauge block as the second plane, the first standard gauge block and the second standard gauge block are exactly the same, the second plane without the coating layer on the surface is closely attached to the coating layer of the first plane, and the relative position of the second plane and the first plane is kept unchanged to form a sample; Step 3, placing the sample in a solution, wherein the solution can dissolve the coating layer but cannot dissolve the first plane and the second plane, and the solution completely immerses the first plane, the coating layer and the second plane at the same time, and when the coating layer is dissolved, a deep slit is formed between the first plane and the second plane, and deep slits of different depths can be obtained according to different dissolution times. The longer the dissolution time, the deeper the deep slit, and the shorter the dissolution time, the shallower the deep slit; Step 4: Measure the size of the deep slit by microscope observation. If a sample does not meet the requirements, repeat steps 1 to 3 multiple times to select a deep slit sample at the micron level that meets the depth requirements from multiple samples.

2. The method for preparing a deep slit for measurement according to claim 1, characterized in that: In the step 1, the coating layer is a silver coating layer, a copper coating layer, a zinc coating layer or a cadmium coating layer.

3. The method for preparing a deep slit for measurement according to claim 1, characterized in that: In the step 1, the coating layer is formed by electroplating.

4. The method for preparing a deep slit for measurement according to claim 1, characterized in that: In the step 2, the first plane and the second plane are connected and fixed by welding to ensure that the relative position of the second plane and the first plane remains unchanged, thereby forming a sample.

5. The method for preparing a deep slit for measurement according to claim 1, characterized in that: In the step 1, the coating layer is an electroplated silver layer, and the electroplating method comprises the following steps performed in sequence: For hanging, use copper wire to clamp the first plane; Degreasing: the first plane surface after degreasing can be completely covered by the water film; Wash with hot water, wash the first surface with hot water; Wash with cold water, clean the first surface with cold water; Weak etching, using hydrochloric acid or sulfuric acid to etch the first plane; Silver electroplating: performing silver electroplating on the surface of the first plane; Wash with running cold water, use running cold water to rinse the silver-plated layer; Disassembly and drying: disassembly of the first plane with the silver-plated layer and the copper wire, and then drying the first plane and the silver-plated layer.

6. The method for preparing a deep slit for measurement according to claim 5, characterized in that: In the silver electroplating step, the silver electroplating bath solution includes 20-30 g / L of silver, 45-80 g / L of potassium cyanide, and 15-50 g / L of potassium carbonate.

7. The method for preparing a deep slit for measurement according to claim 5, characterized in that: In the silver electroplating step, the current density during electroplating is 0.3 to 0.8 amperes per square decimeter, the electroplating temperature is 15 to 35 degrees Celsius, and the electroplating time is 20 to 40 minutes.

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