Polycrystalline diamond compact and preparation method thereof

Abstract

The invention relates to a polycrystalline diamond compact and a preparation method thereof, and belongs to the field of polycrystalline diamond compact processing. The compact comprises a hard alloy matrix and a diamond layer covering the hard alloy matrix, and further comprises a plurality of micro holes embedded in the diamond layer, and the depth of each micro hole is 100-500 microns. According to the polycrystalline diamond compact, the micropores are formed in the diamond layer, so that the cobalt removal quality of the whole diamond layer can be changed, the thermal stability and the wear resistance of the polycrystalline diamond compact are improved, and the service life of the polycrystalline diamond compact is prolonged; and the aperture size, the inclination angle, the spacing and the layout of the micropores can be flexibly set according to actual requirements, so that the polycrystalline diamond compact suitable for different stratums is obtained.

Description

Technical Field

[0001] The invention belongs to the field of polycrystalline diamond composite sheet processing, and in particular relates to a polycrystalline diamond composite sheet and a preparation method thereof. Background Art

[0002] With the continuous advancement of domestic oil and gas exploration and development, the number of risk exploration wells, deep wells, ultra-deep wells and horizontal wells has increased year by year, and the formations encountered have become increasingly complex. Polycrystalline diamond composite sheets are the main cutting elements of PDC drill bits. Improving the wear resistance and thermal stability of diamond composite sheets is crucial to extending the service life of PDC drill bits and reducing the number of drilling trips. In view of the problems encountered by existing cobalt removal technology, such as slow speed and difficult to control effects, and the improvement of diamond composite sheet synthesis technology, the existing cobalt removal technology and process face major challenges. Summary of the invention

[0003] In view of the above problems, the present invention provides a polycrystalline diamond composite sheet and a preparation method thereof. The present invention adopts a continuous laser to perform laser processing on the surface of the diamond composite sheet, which can make micro holes at set positions of the diamond layer, and expand the contact range of the pickling by increasing the depth of the pickling liquid immersed in the diamond composite sheet.

[0004] The first object of the present invention is to provide a polycrystalline diamond composite sheet, comprising a cemented carbide substrate and a diamond layer covering the cemented carbide substrate, and also comprising a plurality of micropores embedded in the diamond layer.

[0005] Furthermore, the depth of the micropores is 100-500 μm.

[0006] Furthermore, the diameter of the micropores is 10-50 μm.

[0007] Furthermore, the angle between the micropore and the diamond surface is α, and α is 0°-90°.

[0008] Furthermore, the plurality of micropores are evenly distributed throughout the entire diamond layer.

[0009] Furthermore, a plurality of the micropores are evenly distributed along the edge of the diamond layer.

[0010] Furthermore, a plurality of the micropores are evenly distributed in a local area of ​​the diamond.

[0011] A second object of the present invention is to provide a method for preparing a polycrystalline diamond compact, comprising:

[0012] The surface of the initial polycrystalline diamond composite sheet is laser processed by using a continuous laser to form micro holes on the diamond layer to obtain a polycrystalline diamond composite sheet.

[0013] Furthermore, in the laser processing, the focal length of the focusing mirror used is 90 mm to 150 mm.

[0014] Furthermore, in the laser processing, the power is between 35-55J, and the single-point continuous light emission time is 9-15 seconds.

[0015] Beneficial effects of the present invention:

[0016] The polycrystalline diamond composite sheet provided by the present invention can change the decobaltization quality of the overall diamond layer by setting micropores on the diamond layer, thereby improving the thermal stability and wear resistance of the polycrystalline diamond composite sheet, thereby extending the service life of the polycrystalline diamond composite sheet;

[0017] Moreover, the aperture size, inclination, spacing and layout of the micropores can be flexibly set according to actual needs to obtain polycrystalline diamond composite sheets adapted to different strata, further improving the practical application and promotion of the obtained polycrystalline diamond composite sheets.

[0018] The present invention can also set micropores in some areas according to the main cutting area of ​​the diamond layer when it is working, further enhance the quality and effect of decobalting, and improve the local thermal stability and wear resistance of the diamond composite sheet;

[0019] The polycrystalline diamond composite sheet provided by the present invention adopts a continuous laser to perform laser processing on the surface of the diamond composite sheet, and can punch micro holes at set positions of the diamond layer. The size, inclination angle, spacing and layout of the hole diameter can be set by the specific process parameters of the laser processing. The preparation method is simple and easy to operate.

[0020] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 A schematic diagram of a polycrystalline diamond compact according to an embodiment of the present invention is shown;

[0023] Figure 2 A perspective view showing micro holes embedded in a diamond layer according to an embodiment of the present invention is shown;

[0024] Figure 3 A schematic diagram showing the distribution of micropores on the diamond layer according to Example 1 and Example 2 of the present invention is shown;

[0025] Figure 4 A schematic diagram showing the effect of the diamond layer before and after decobalting according to Comparative Example 1 of the present invention is shown;

[0026] Figure 5 A schematic diagram showing the effect of the diamond layer before and after decobalting according to Example 1 of the present invention is shown;

[0027] Figure 6 A schematic diagram showing the effect of the diamond layer before and after decobalting according to Example 2 of the present invention is shown;

[0028] Figure 7 A schematic diagram showing the distribution of micropores on a diamond layer according to an embodiment of the present invention is shown;

[0029] In the figure:

[0030] 201, diamond layer; 202, cemented carbide substrate; 203, micropores; 204, decobaltized area. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] like Figure 1 A polycrystalline diamond composite sheet is shown, comprising a cemented carbide substrate 202 and a diamond layer 201 covering the cemented carbide substrate 202;

[0033] like Figure 2 As shown, the polycrystalline diamond compact further includes a plurality of micro holes 203 embedded in the diamond layer 201 .

[0034] In the embodiment of the present invention, the depth of the micropore 203 is 100-500 μm, and the depth of the micropore 203 is 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm, 190 μm, 200 μm, 210 μm, 220 μm, 230 μm, 240 μm, 250 μm, 260 μm, 270 μm, Any one of 0μm, 280μm, 290μm, 300μm, 310μm, 320μm, 330μm, 340μm, 350μm, 360μm, 370μm, 380μm, 390μm, 400μm, 410μm, 420μm, 430μm, 440μm, 450μm, 460μm, 470μm, 480μm, 490μm, and 500μm.

[0035] In the embodiment of the present invention, the diameter of the micro hole 203 is 10-50 μm, and the diameter of the micro hole 203 is any one of 10 μm, 20 μm, 30 μm, 40 μm, and 50 μm.

[0036] In an embodiment of the present invention, the angle between the micropore 203 and the diamond surface is α, α is 0°-90°, and α is any one of 0°, 5°, 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, 50°, 45°, 60°, 65°, 70°, 75°, 80°, 85°, and 90°.

[0037] In the embodiment of the present invention, the plurality of micropores 203 are evenly distributed throughout the diamond layer 201. Figure 7 As shown in a; the plurality of micropores 203 may also be evenly distributed along the edge of the diamond layer 201, such as Figure 7 As shown in b; some of the micropores 203 can also be evenly distributed in a local area of ​​the diamond, such as Figure 7 As shown in c.

[0038] A method for preparing a polycrystalline diamond compact according to an embodiment of the present invention includes:

[0039] The surface of the initial polycrystalline diamond compact is laser processed using a continuous laser to make micro holes 203 on the diamond layer 201 to obtain a polycrystalline diamond compact.

[0040] In the laser processing, the focal length of the focusing mirror used is 90mm-150mm, the power is between 35-55J, and the single-point continuous light emission time is 9-15 seconds.

[0041] In the embodiment of the present invention, during the laser processing, the diameter of the obtained micro hole 203 is controlled by adjusting the focal length of the focusing lens and the duration of the single-point continuous light emission.

[0042] In the embodiment of the present invention, in the laser processing, when the focal length and power are constant, the longer the single point duration is, the larger the diameter of the microhole 203 is and the deeper the depth is; the shorter the single point duration is, the smaller the diameter of the microhole 203 is and the smaller the depth is.

[0043] In the embodiment of the present invention, during the laser processing, the angle between the micro hole 203 and the diamond surface is adjusted by adjusting the incident angle formed by the light source of the continuous laser and the initial polycrystalline diamond compact, and the two angles are equal.

[0044] In the embodiment of the present invention, during the laser processing, the distribution of the obtained micro holes 203 and the spacing between the micro holes 203 are controlled by an array function, and the array types include circular and rectangular.

[0045] Example 1

[0046] Polycrystalline Diamond Composite Plate

[0047] The polycrystalline diamond composite sheet is prepared by using the above-mentioned method, wherein in the laser processing, the focal length of the focusing lens used is 90 mm, the power is between 45 J, and the single point continuous light emission time is 9 seconds;

[0048] The distribution patterns of some of the micropores 203 are as follows: Figure 3 shown.

[0049] The angle α between the obtained micropore 203 and the diamond surface is 90°.

[0050] Example 2

[0051] Polycrystalline Diamond Composite Plate

[0052] The polycrystalline diamond composite sheet is prepared by using the above-mentioned method, wherein in the laser processing, the focal length of the focusing lens used is 90 mm, the power is between 45 J, and the single point continuous light emission time is 9 seconds;

[0053] The distribution patterns of some of the micropores 203 are as follows: Figure 3 shown.

[0054] The angle α between the obtained micropore 203 and the diamond surface is 30°.

[0055] Comparative Example 1

[0056] The polycrystalline diamond compact is the initial polycrystalline diamond compact in Example 1.

[0057] Example 2

[0058] The laser treated diamond composite sheets (Example 1 and Example 2) and the untreated composite sheet (Comparative Example 1) were subjected to cobalt removal treatment under the same conditions and measured using an X-ray detection system. The results are shown in the figure below: Figure 4-Figure 6 As shown in Figure 4 Figure a is a schematic diagram of the X-ray detection system measurement of the polycrystalline diamond composite sheet before decobalting in Comparative Example 1, Figure 4 b is a schematic diagram of the X-ray detection system measurement of the polycrystalline diamond composite sheet after decobalting in Comparative Example 1; Figure 5 Figure a is a schematic diagram of the X-ray detection system for measuring the polycrystalline diamond composite sheet before decobalting in Example 1. Figure 5 b is a schematic diagram of the X-ray detection system measuring the polycrystalline diamond composite sheet after decobalting in Example 1, Figure 6 Figure a is a schematic diagram of the X-ray detection system for measuring the polycrystalline diamond composite sheet before decobalting in Example 2. Figure 6 b is a schematic diagram of the X-ray detection system measurement of the polycrystalline diamond composite sheet after decobalting in Example 2, Figure 4-Figure 6 In the middle, 204 is the decobaltization area;

[0059] from Figure 4-Figure 6 As can be seen from the figure, the contact range and depth between the chemical agent used for decobalting and the diamond layer 201 are increased by setting the micropores 203, which greatly improves the decobalting quality. Figure 6 It can be seen that by setting the inclined hole in the middle of the diamond composite sheet, ultra-deep cobalt removal can be achieved on the local edge area of ​​the cutting tooth, solving the influence of the micro holes 203 set at the edge position on the durability of the diamond composite sheet.

[0060] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A polycrystalline diamond composite sheet, comprising a cemented carbide substrate (202) and a diamond layer (201) covering the cemented carbide substrate (202), characterized in that: It also includes a plurality of micro holes (203) embedded in the diamond layer (201).

2. The polycrystalline diamond compact according to claim 1, characterized in that: The depth of the micropores (203) is 100-500 μm.

3. The polycrystalline diamond compact according to claim 1, characterized in that: The diameter of the micropores (203) is 10-50 μm.

4. The polycrystalline diamond compact according to claim 1, characterized in that: The angle between the micropore (203) and the diamond surface is α, and α is 0°-90°.

5. The polycrystalline diamond compact according to claim 1, characterized in that: The plurality of micropores (203) are evenly distributed throughout the entire diamond layer (201).

6. The polycrystalline diamond compact according to claim 1, characterized in that: The plurality of micropores (203) are evenly distributed along the edge of the diamond layer (201).

7. The polycrystalline diamond compact according to any one of claims 1 to 6, characterized in that: A plurality of the micropores (203) are evenly distributed in a local area of ​​the diamond.

8. A method for preparing a polycrystalline diamond composite sheet, characterized in that: The polycrystalline diamond composite sheet according to any one of claims 1 to 6 is made, comprising: A continuous laser is used to perform laser processing on the surface of an initial polycrystalline diamond composite sheet, and micro holes (203) are punched on a diamond layer (201) to obtain a polycrystalline diamond composite sheet.

9. The method for preparing a polycrystalline diamond compact according to claim 8, characterized in that: In the laser processing, the focal length of the focusing mirror used is 90 mm to 150 mm.

10. The method for preparing a polycrystalline diamond compact according to claim 8, characterized in that: In the laser processing, the power is between 35-55J, and the single-point continuous light emission time is 9-15 seconds.

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