Diamond compact and processing method therefor

Abstract

A diamond compact and a processing method therefor. The diamond compact comprises a substrate (1) and a diamond layer (2), wherein the diamond layer (2) is arranged on one side of the substrate (1); surfaces of the substrate (1) and the diamond layer (2) opposite each other are respectively a substrate composite surface (3) and a diamond layer composite surface (4); the substrate composite surface (3) and the diamond layer composite surface (4) mate with each other by means of first protrusion structures (5) and groove structures (6), which are respectively formed on at least one of the substrate composite surface (3) and the diamond layer composite surface (4); a plurality of substrate holes (7) are further formed in the substrate composite surface (3); second protrusion structures (12) matching the substrate holes (7) are formed in the diamond layer (2); and the depth of each of the substrate holes (7) is greater than the depth of the groove structure (6). The diamond compact has a strong impact resistance and a low interface residual stress.

Description

Diamond compact and method of manufacturing the same

[0001] Cross-reference to Related Applications

[0002] This application claims the benefit of Chinese Patent Application No. 202411318413.4, filed September 20, 2024, the contents of which are incorporated herein by reference. TECHNICAL FIELD

[0003] The present invention relates to a composite material for oil drilling, in particular, to a diamond compact, and further relates to a method of manufacturing the diamond compact. BACKGROUND

[0004] With the continuous advancement of oil and gas exploration and development, the number of drilled wells for risk exploration, deep wells, ultra-deep wells, and horizontal wells increases year by year, the drilled strata gradually become complex, and it is crucial to prolong the service life of PDC (polycrystalline diamond compact bit) drill bits and reduce the number of trips.

[0005] The main forms of failure of the cutting teeth of the PDC drill bit are normal wear, piece dropping, edge collapse, and delamination, etc. The delamination refers to the separation of the diamond layer of the compact of the PDC drill bit from the hard alloy substrate. The main reason for the separation is that there is a large residual stress between the diamond layer and the hard alloy substrate of the cutting tooth, and the thermal expansion coefficients of the substrate and the diamond layer are significantly different. Thus, in the process of cutting rock, the diamond layer and the hard alloy substrate do not shrink synchronously under the thermal stress generated by friction and the cooling effect of the flushing fluid, and the impact load and the residual stress cause the diamond layer to peel off from the hard alloy substrate, resulting in the failure of the drill bit.

[0006] The substrate of the prior art adopts a non-planar interface design, i.e., various shaped grooves or protrusions are arranged on the composite surface of the substrate. These grooves or protrusions are only extended on the composite surface. The prior art only adjusts the shape of the grooves or protrusions, and does not form a connecting structure combining the grooves along the radial direction of the substrate and the holes along the axial direction of the substrate. The improvement of the impact resistance of the diamond compact is limited, and the interface residual stress of the diamond compact cannot be effectively reduced. Under the action of the impact load and the residual stress, the diamond layer is prone to peel off from the substrate, resulting in a short service life of the diamond compact.

[0007] Therefore, it is necessary to design a diamond compact with high bonding strength between the diamond layer and the hard alloy substrate, low interface residual stress, and strong impact resistance. SUMMARY

[0008] One of the purposes of the present application is to provide a diamond compact with high impact resistance, low interfacial residual stress and long service life.

[0009] Another purpose of the present application is to provide a processing method of diamond compact, and the diamond compact processed by the processing method has high impact resistance, low interfacial residual stress and long service life.

[0010] In order to achieve the above-mentioned purposes, the present application provides a diamond compact, which comprises a base body and a diamond layer, the diamond layer is arranged on one side of the base body, the surfaces of the base body and the diamond layer opposite to each other are respectively a base body composite surface and a diamond layer composite surface, the base body composite surface and the diamond layer composite surface are matched by a plurality of first protruding structures and a plurality of groove structures matched with each other, the first protruding structures and the groove structures are respectively formed on at least one of the base body composite surface and the diamond layer composite surface, the base body composite surface is further provided with a plurality of base body holes, the diamond layer is provided with second protruding structures matched with the base body holes, the depth of the base body hole is greater than the depth of the groove structure, the diameter of the base body hole is 0.5-1.5mm, the depth is 1-3mm, and the distance between two adjacent base body holes is greater than or equal to twice the diameter of the base body hole and less than or equal to three times the diameter of the base body hole.

[0011] Preferably, the base body hole is perpendicular to the base body composite surface.

[0012] Preferably, the plurality of base body holes are arranged in an array to form a base body hole array.

[0013] Specifically, the base body is a cylindrical structure.

[0014] Preferably, the base body hole array is a ring array or a semicircular array.

[0015] Preferably, the first protruding structure is arranged on the base body composite surface, and the groove structure is arranged on the diamond layer composite surface, and optionally, the plurality of base body holes arranged in a ring array are distributed outward from the center of the base body composite surface in the radial direction to divide the base body composite surface into a plurality of fan-shaped regions, at least one first protruding structure is arranged in each fan-shaped region, and the length direction of the first protruding structure extends along the radial direction of the base body composite surface.

[0016] Preferably, the substrate hole array is arranged to form two semi-circular arrays, and the two semi-circular arrays are symmetrically arranged with the diameter of the substrate complex surface as the axis of symmetry. Optionally, the first protruding structure is provided in multiple groups, and multiple first protruding structures are provided in each group. The first protruding structures in adjacent groups are arranged at intervals, and the interval between adjacent first protruding structures in each group is equal.

[0017] Preferably, a plurality of annular grooves are formed on the substrate complex surface, and the plurality of annular grooves are distributed outward from the center of the substrate complex surface in the radial direction. An annular surface is formed between adjacent annular grooves, and the plurality of substrate holes are uniformly distributed around the annular surface.

[0018] To achieve the above-mentioned purpose, another aspect of the present application provides a processing method of a diamond compact, which comprises the following steps:

[0019] A) processing a plurality of substrate holes and the first protruding structure and / or groove structure on one side surface of the substrate.

[0020] B) filling mixed raw materials for forming a diamond layer on the above-mentioned side surface and then sintering.

[0021] Preferably, the step of filling the mixed raw materials for forming a diamond layer on the above-mentioned side surface comprises: first filling the mixed raw materials into the substrate holes, and then filling the mixture onto the side surface.

[0022] Specifically, the mixed raw materials contain a binder and diamond powder.

[0023] Preferably, the particle size of the diamond powder is 10-100 microns.

[0024] By the technical scheme, the side surface of the diamond compact body contacting with the diamond layer is a body composite surface, at least one of the body composite surface and the diamond layer composite surface is formed with a plurality of first protruding structures, and the other is formed with groove structures matched with the first protruding structures, so that the groove structures and the first protruding structures form first connecting structures on the composite surface, the first connecting structures can increase the contact area of the body and the diamond layer, thereby improving the interface bonding strength of the body and the diamond layer, and the ability of the diamond compact to resist external impact is improved. In addition to the first protruding structures and the groove structures corresponding to the first protruding structures, the body composite surface is formed with a plurality of body holes, the diamond layer is formed with second protruding structures corresponding to the body holes, the second protruding structures extend into the plurality of body holes, and the body holes and the second protruding structures form second connecting structures. The second protruding structures extending into the body can contact the body holes, increase the bonding area between the body and the diamond layer, improve the interface bonding strength of the body and the diamond layer, and enhance the ability of the diamond compact to resist external impact. In addition, since the depth of the body hole is greater than the depth of the groove structure, and the length of the second protruding structure is greater than the length of the first protruding structure, the second connecting structure can extend the length of the bonding interface of the body and the diamond layer along the axial direction of the diamond compact, and the connecting structure combined with the first connecting structure and the second connecting structure has higher interface bonding strength, can better eliminate the interface residual stress between the body and the diamond layer, and further enhances the ability of the diamond compact to resist external impact. BRIEF DESCRIPTION OF DRAWINGS

[0025] FIG. 1 is an exploded view of the diamond compact of the embodiment of the present application;

[0026] FIG. 2 is a longitudinal sectional view of the diamond compact formed by sintering the body and the diamond layer shown in FIG. 1;

[0027] FIG. 3 is a top view of the body of the embodiment of the present application;

[0028] FIG. 4 is a top view of the body of another embodiment of the present application;

[0029] FIG. 5 is a longitudinal sectional view of the diamond compact formed by sintering the body and the diamond layer shown in FIG. 4.

[0030] Reference signs 1- body, 2- diamond layer, 3- body composite surface, 4- diamond layer composite surface, 5- first protruding structure, 6- groove structure, 7- body hole, 8- annular array, 9- semicircular array, 10- annular groove, 11- annular surface, 12- second protruding structure. DETAILED DESCRIPTION

[0031] The embodiments of the present application will be described in further detail below with reference to the drawings and embodiments. The following detailed description of the embodiments and the drawings are provided to illustrate the principles of the present application, and should not be interpreted to limit the scope of the present application, which can be implemented in a number of different forms, not limited to the specific embodiments disclosed herein, but including all the technical solutions falling within the scope of the claims.

[0032] The present application provides these embodiments is to make the present application and complete, and to the person skilled in the art fully express the scope of the present application. It should be noted that: unless otherwise specified, the relative arrangement of components and steps, the composition of materials, numerical expressions and values set forth in these embodiments should be interpreted as merely exemplary, and not as limiting.

[0033] It should be noted that, in the description of the present application, unless otherwise specified, the meaning of "a plurality of" is greater than or equal to two; The orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer" and the like is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0034] In addition, "first", "second" and similar words used in the present application do not represent any order, number or importance, but are only used to distinguish different parts. "Vertical" is not strictly vertical, but within the allowable range of error. "Include" or "contain" and similar words mean that the elements before the word cover the elements listed after the word, and do not exclude the possibility of also covering other elements.

[0035] It should also be noted that, in the description of the present application, unless otherwise specifically provided and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; It can be directly connected, or indirectly connected through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances. When a specific device is described to be located between a first device and a second device, there can be an intermediate device between the specific device and the first device or the second device, or there can be no intermediate device.

[0036] All terms used in the present application have the same meaning as understood by those skilled in the art to which the present application belongs, unless otherwise specifically defined. It should also be understood that terms defined in general dictionaries should be interpreted to have meanings consistent with their meanings in the context of the relevant technology, and should not be interpreted in an idealized or excessively formalized sense, unless otherwise defined herein.

[0037] Techniques, methods, and apparatus known to those of ordinary skill in the relevant art(s) can not be discussed in any detail, but should be considered as part of the specification to the extent that they are not otherwise fully disclosed.

[0038] As shown in FIG. 1, the diamond compact of the present application comprises a substrate 1 and a diamond layer 2, the diamond layer 2 is arranged on one side of the substrate 1, the surfaces of the substrate 1 and the diamond layer 2 opposite to each other are a substrate complex surface 3 and a diamond layer complex surface 4 respectively, the substrate complex surface 3 and the diamond layer complex surface 4 are matched by a plurality of first protruding structures 5 and a plurality of groove structures 6, the first protruding structures 5 and the groove structures 6 are formed on at least one of the substrate complex surface 3 and the diamond layer complex surface 4 respectively. In this embodiment, the substrate complex surface 3 is formed with a plurality of first protruding structures 5, and the diamond layer complex surface 4 is formed with groove structures 6 matched with the first protruding structures 5, in other embodiments, the substrate complex surface 3 is formed with a plurality of groove structures 6, and the diamond layer complex surface 4 is formed with first protruding structures 5 matched with the groove structures 6, or the substrate complex surface 3 and the diamond layer complex surface 4 are both formed with a plurality of first protruding structures 5 and groove structures 6, the first protruding structures 5 on the substrate complex surface 3 are matched with the groove structures 6 on the diamond layer complex surface 4, and the groove structures 6 on the substrate complex surface 3 are matched with the first protruding structures 5 on the diamond layer complex surface 4. The first protruding structures 5 are accommodated in the groove structures 6 and combined to form a first connecting structure, the first connecting structure is a two-dimensional connecting structure extending on the bonding surface of the substrate 1 and the diamond layer 2, which can increase the bonding area of the substrate 1 and the diamond layer 2, improve the interfacial bonding strength of the substrate 1 and the diamond layer 2, enhance the ability of the diamond compact to resist external impact, and reduce the residual stress between the substrate 1 and the diamond layer 2. On the basis of the first connecting structure, a plurality of substrate holes 7 are further formed on the substrate complex surface 3 of the diamond compact of the present application, the diamond layer 2 forms a plurality of second protruding structures 12 corresponding to the substrate holes 7, the second protruding structures 12 extend into the substrate holes 7, the depth of the substrate holes 7 is greater than the depth of the groove structures 6, the height of the second protruding structures 12 is greater than the height of the first protruding structures 5, the plurality of substrate holes 7 and the second protruding structures 12 combine to form a second connecting structure, the axis direction of the substrate holes 7 and the first connecting structure form an included angle, the included angle is greater than 0° and less than or equal to 90°, so as shown in FIG. 5, compared with the substrate 1 only provided with the first protruding structures 5 and / or the groove structures 6 on the substrate complex surface 3, the diamond compact of the present application extends the length of the bonding interface of the substrate 1 and the diamond layer 2 in the axial direction of the substrate 1 by additionally providing the second connecting structure formed by the cooperation of the substrate holes 7 and the second protruding structures 12, so that the bonding transition of the diamond compact is better, the bonding strength of the substrate 1 and the diamond layer 2 is higher, the stress dispersion ability is improved, the interfacial residual stress is better reduced, and the impact resistance of the diamond compact is further enhanced.Further, in some use states of the diamond compact of the present application, such as in the process of cutting rock, the thermal expansion coefficients of the substrate 1 and the diamond layer 2 are different, and under the action of thermal stress generated by friction and flushing coolant, the contraction of the substrate 1 and the diamond layer 2 is not synchronized, but due to the better impact resistance and the better ability to reduce residual stress of the diamond compact of the present application, the substrate 1 and the diamond layer 2 are less likely to separate under the action of impact load and residual stress, and the service life of the diamond compact is longer.

[0039] As a preferred embodiment, as shown in FIG. 2, a plurality of first protruding structures 5 are formed on the substrate composite surface 3 of the substrate 1, and a plurality of groove structures 6 matching the first protruding structures 5 are formed on the diamond layer composite surface 4 of the diamond layer 2, the first protruding structures 5 and the groove structures 6 cooperate to form a first connecting structure, and on the basis of the first connecting structure, a plurality of substrate holes 7 are further formed on the substrate composite surface 3 of the substrate 1, the substrate holes 7 are perpendicular to the substrate composite surface 3, so that the substrate holes 7 of this embodiment are arranged along the axial direction of the substrate 1 and are perpendicular to the first protruding structures 5 or the groove structures 6 on the substrate composite surface 3, the substrate holes 7 arranged along the axial direction of the substrate 1 can lengthen the length of the bonding interface between the substrate 1 and the diamond layer 2 in the axial direction of the substrate 1, and the first connecting structure formed along the radial direction of the substrate 1 and the second connecting structure formed along the axial direction of the substrate 1 are combined to form a three-dimensional connecting structure, so that the diamond compact of this embodiment has a higher bonding strength between the substrate 1 and the diamond layer 2, effectively reduces the interface residual stress between the substrate 1 and the diamond layer 2, improves the impact resistance of the diamond compact, and further prolongs the service life of the diamond compact.

[0040] In the present application, "perpendicular" means perpendicular within an error tolerance range, and there can be perpendicular or near-perpendicular conditions, for example, the angle between the substrate hole 7 and the substrate composite surface 3 is 89°, or the angle between the substrate hole 7 and the substrate composite surface 3 is 91°, which can also be considered as perpendicular.

[0041] As a preferred embodiment, as shown in FIG. 2, a plurality of substrate holes 7 are formed on the substrate composite surface 3, the diameter of the substrate hole 7 is 0.5mm-1.5mm, and the depth of the substrate hole 7 is 1mm-3mm. Preferably, the depth of the substrate hole 7 is 2-3 times the hole diameter, and the second connecting structure of this embodiment makes the bonding area between the substrate 1 and the diamond layer 2 larger, and the structural strength of the second connecting structure of this embodiment is higher.

[0042] Further, the size of the diamond compact is usually 13, 16, 19 mm, and when the diameter of the substrate hole 7 is between 0.5-1.5 mm, the distance between adjacent substrate holes 7 is greater than or equal to the diameter of the substrate hole 7 and less than or equal to three times the diameter of the substrate hole 7, and as a preferred embodiment, the distance between adjacent substrate holes 7 is greater than or equal to twice the diameter of the substrate hole 7 and less than or equal to three times the diameter of the substrate hole 7, the size of the diamond compact, the diameter of the substrate hole 7 and the distance between the substrate holes 7 of the preferred embodiment make the number of substrate holes 7 on the substrate complex surface 3 more appropriate, the structural strength of the second connecting structure is higher, and the bonding strength and structural strength of the diamond compact of the embodiment achieve a balance, so that the service life of the diamond compact of the embodiment is longer. In addition, the total area of the substrate hole 7 does not exceed 50% of the area of the substrate complex surface 3, so as to avoid the structural strength of the substrate 1 being too low.

[0043] As a preferred embodiment, as shown in FIG. 1, FIG. 3 and FIG. 4, the substrate complex surface 3 of the substrate 1 is formed with a plurality of substrate holes 7, and the plurality of substrate holes 7 are arranged in an array to form a substrate hole array, and the array arrangement of the plurality of substrate holes 7 improves the uniformity of stress dispersion, avoids local stress damage caused by stress concentration, and further prolongs the service life of the diamond compact. As a preferred embodiment, as shown in FIG. 1, FIG. 3 and FIG. 4, the first protruding structure 5 and / or the groove structure 6 on the substrate complex surface 3 of the substrate 1 are also arranged in an array, so as to further improve the uniformity of stress dispersion, avoid local stress damage caused by stress concentration, and further prolong the service life of the diamond compact.

[0044] As a specific embodiment, as shown in FIG. 1, the substrate 1 is a cylindrical structure. On this basis, as a preferred embodiment, the substrate holes on the substrate complex surface 3 are uniformly arranged to make the stress dispersion uniform, further enhance the bonding strength, so that the diamond compact has stronger ability to resist external impact. As shown in FIG. 1, FIG. 3 and FIG. 4, the substrate 1 of the three embodiments is a cylindrical substrate, and the substrate hole array can be but is not limited to a ring array, a semicircular array, a circular array, so that the stress dispersion effect of the substrate hole array of the illustrated embodiment is better, and the ability of the diamond compact to resist external impact is improved.

[0045] As a preferred embodiment, the substrate 1 is a tungsten carbide substrate, and the diamond layer 2 is sintered from a mixed raw material composed of diamond powder and a binder. The binder of this embodiment is cobalt, the bonding transition of the diamond layer 2 and the tungsten carbide substrate of this preferred embodiment is better, the bonding strength is higher, and the ability to resist external impact is stronger.

[0046] The present application provides three preferred embodiments of the arrangement of the first protruding structure 5, the groove structure 6, the second protruding structure 12 and the substrate hole 7.

[0047] As shown in FIG. 1, the first protruding structure 5 of the first embodiment is arranged on the substrate composite surface 3, and the groove structure 6 is arranged on the diamond layer composite surface 4, wherein a plurality of substrate holes 7 arranged in a ring array 8 are distributed outward from the center of the substrate composite surface 3 in the radial direction, so as to divide the substrate composite surface 3 into a plurality of fan-shaped regions, and at least one first protruding structure 5 is arranged in each fan-shaped region, and the number of first protruding structures 5 in each fan-shaped region is equal and the positions are basically the same. In this first embodiment, one first protruding structure 5 is arranged in each fan-shaped region, and the first protruding structure 5 is arranged along the symmetry axis of the corresponding fan-shaped region, and the length direction of the first protruding structure 5 extends along the radial direction of the substrate composite surface 3. And the plurality of substrate holes 7 arranged in the ring array 8 of this embodiment form a plurality of substrate hole columns, and two adjacent substrate hole columns separate the substrate composite surface 3 to form a fan-shaped region. In this embodiment, the included angle between each substrate hole column is the same, and the included angle between each substrate hole column can be set to but not limited to 45°, 60°, 90°, 120°.

[0048] As shown in FIG. 3, the substrate holes 7 of the second embodiment are arranged in an array to form two semicircular arrays 9, which are symmetrically arranged on the substrate composite surface 3 with the diameter of the substrate composite surface 3 as the symmetry axis. The first protruding structure 5 is arranged in multiple groups, each group has a plurality of first protruding structures 5, and the first protruding structures 5 in adjacent two groups are arranged at intervals, and the interval between the two adjacent first protruding structures 5 in each group is equal. Here, "equal" means equal within an error allowable range.

[0049] As shown in FIG. 4, the substrate composite surface 3 of the third embodiment is formed with a plurality of annular grooves 10, which are distributed outward from the center of the substrate composite surface 3 in the radial direction, and the distance between the two adjacent annular grooves 10 is equal, and the annular surface 11 is formed between the two adjacent annular grooves 10, and a plurality of substrate holes 7 are uniformly distributed around the annular surface 11.

[0050] The results of the wear resistance and impact resistance tests of the diamond composite pieces of the first to third embodiments and the corresponding reference teeth in the indoor test are shown in Table 1.

[0051] Table 1

[0052] As can be seen from the results of Table 1, the above-mentioned embodiments one to three of the present application form a plurality of base holes 7 on the base complex surface 3, and fill the base holes 7 with diamond powder, and compared with the benchmark tooth without the base holes 7, the abrasion resistance and impact resistance of the embodiments one to three of the present application have obviously better effects. And the above-mentioned embodiments one to three are preferred embodiments of the present application, the first protruding structure 5, the groove structure 6, the second protruding structure 12 and the base hole 7 are arranged relatively uniformly, so that the stress dispersion is relatively uniform, and stress concentration is not easy to appear, so that local damage is not easy to appear, and then the service life of the above-mentioned embodiments one to three is longer.

[0053] As shown in Figure 4, the application provides a preferred diamond compact, which comprises a substrate 1 and a diamond layer 2, the substrate 1 and the diamond layer 2 are both cylindrical bodies with a diameter of 16 mm, the substrate 1 is a tungsten carbide hard alloy substrate, the diamond layer 2 is arranged on one side of the substrate 1, the opposite side surfaces of the substrate 1 and the diamond layer 2 are substrate composite surfaces 3 and diamond layer composite surfaces 4 respectively, a plurality of annular grooves 10 are formed on the substrate composite surfaces 3, the plurality of annular grooves 10 are distributed outwardly along the radial direction of the substrate composite surfaces 3 from the center position of the substrate composite surfaces 3, the distance between adjacent two annular grooves 10 is equal, the diamond layer composite surfaces 4 of the diamond layer 2 form annular protrusions corresponding to the annular grooves 10, annular surfaces 11 are formed between adjacent two annular grooves 10, a plurality of uniformly arranged substrate holes 7 are formed around the annular surfaces 11, the diameter of the substrate holes 7 is 1 mm, the depth of the substrate holes 7 is 3 mm, and the distance between adjacent two substrate holes 7 is 2-3 mm. The substrate 1 of the preferred embodiment is a tungsten carbide hard alloy substrate, the combination of the tungsten carbide hard alloy substrate and the diamond layer 2 has better transition and higher strength, and the ability to resist external impact is stronger. The annular grooves 10 formed on the substrate composite surfaces 3 of the substrate 1 of the preferred embodiment are combined with the annular protrusions formed on the diamond layer composite surfaces of the diamond layer 2, which increases the bonding area of the substrate 1 and the diamond layer 2, further enhances the bonding strength, and improves the ability of the diamond compact to resist external impact. On the basis of the first connecting structure formed by the combination of the annular grooves 10 and the annular protrusions, the preferred embodiment further forms a plurality of substrate holes 7 on the substrate composite surfaces 3 of the substrate 1, and the plurality of substrate holes 7 form a second connecting structure, which can also increase the bonding area of the substrate 1 and the diamond layer 2, thereby further enhancing the bonding strength and improving the ability of the diamond compact to resist external impact. Moreover, the second connecting structure and the first connecting structure form a certain angle, and in this embodiment, the substrate holes 7 are perpendicular to the first connecting structure, so compared with only arranging the first connecting structure, the embodiment of the application further adds a plurality of substrate holes 7 perpendicular to the first connecting structure and a plurality of second protruding structures 12 corresponding to the plurality of substrate holes 7, and the depth of the substrate holes 7 is greater than the depth of the annular grooves 10, and the height of the second protruding structures 12 is greater than the height of the annular protrusions, thereby prolonging the length of the bonding interface of the substrate 1 and the diamond layer 2 in the axial direction of the diamond compact, so that the first connecting structure and the second connecting structure combine to form a three-dimensional connecting structure, which enhances the ability of the diamond compact to reduce interface residual stress, improves the bonding strength of the substrate composite surfaces 3 and the diamond layer composite surfaces 4, reduces the wear rate, and further improves the ability of the diamond compact to resist external impact. In addition, the distribution of the substrate holes 7 and the annular grooves 10 of the embodiment is relatively uniform, and when the diamond compact is subjected to external impact, stress concentration to a local part to cause local fracture to affect the strength of the overall structure is less likely to occur, thereby prolonging the service life of the diamond compact.In the process of cutting rock, the thermal stress generated by the frictional heat of the cutting teeth and the cooling effect of the flushing liquid cause the contraction of the matrix 1 and the diamond layer 2 to be out of synchronization. However, the diamond layer composite sheet of the preferred embodiment can dissipate more interface residual stress, and the bonding strength of the diamond layer composite sheet of the preferred embodiment is higher and the wear resistance is better, so that the diamond layer 2 is not easy to be peeled off under the action of impact load and residual stress, thereby prolonging the service life of the diamond composite sheet.

[0054] In another aspect, the present application provides a processing method of the diamond composite sheet, which comprises the following steps:

[0055] A) processing a plurality of matrix holes 7 on one side surface of the matrix 1, and processing the first protruding structure 5 and / or the groove structure 6.

[0056] B) filling the mixed raw materials for forming the diamond layer 2 on the above-mentioned side surface and then sintering.

[0057] As a specific embodiment, the mixed raw materials in step B of the method for processing the diamond compact include a binder and diamond powder, the binder can be but is not limited to cobalt, nickel, iron binder, and the mixing mass ratio of the binder and the diamond powder can be determined by the user according to the actual situation. In some specific embodiments, before the mixed raw materials are filled on the side surface of the substrate 1, the substrate 1 is placed in a container with a preset shape, so that the diamond layer 2 formed after sintering of the mixed raw materials is in a preset shape. When the side surface of the substrate 1 forms the groove structure 6, a part of the mixed raw materials filled on the side surface can fall into the groove structure 6, so that the mixed raw materials falling into the groove structure 6 form the first protruding structure 5 after sintering, which can increase the bonding area of the substrate 1 and the diamond layer 2, thereby improving the interfacial bonding strength between the substrate 1 and the diamond layer 2 and the ability of the diamond compact to resist external impact. When the side surface of the substrate 1 forms the first protruding structure 5, the mixed raw materials not falling into the substrate hole 7 form the main part of the diamond layer 2 and the groove structure 6 corresponding to the first protruding structure 5 after sintering. In addition, after the mixed raw materials are filled on the side surface of the substrate 1 on which the substrate hole 7 is processed, the mixed raw materials can fall into the substrate hole 7, and the diamond powder at the substrate hole 7 can extend into the substrate hole 7 and compact the substrate hole 7 after sintering, thereby forming the second protruding structure 12, which can contact the hole wall of the substrate hole 7, thereby increasing the contact area between the substrate 1 and the diamond layer 2 and improving the interfacial bonding strength between the substrate 1 and the diamond layer 2 and the ability of the diamond compact to resist external impact. In addition, since the depth of the substrate hole 7 is greater than the depth of the groove structure 6 and the height of the first protruding structure 5, the second connecting structure formed by a plurality of substrate holes 7 can extend the length of the bonding interface between the substrate 1 and the diamond layer 2 in the axial direction of the substrate 1, thereby improving the transition between the substrate 1 and the diamond layer 2 and further improving the interfacial bonding strength between the substrate 1 and the diamond layer 2 and the ability of the diamond compact to resist external impact. In other specific embodiments, after the substrate 1 is processed with a plurality of substrate holes 7 and the first protruding structure 5 and / or the groove structure 6, the substrate 1 is placed in a container filled with mixed raw materials, and the mixed raw materials and the substrate 1 are pressed to synthesize the diamond compact under high temperature and high pressure conditions.

[0058] As a preferred embodiment, the particle size of the diamond powder is 10-100 microns, and the diamond powder with the preferred particle size range is easy to fall into the matrix holes 7 when the mixed raw materials are filled into the side surface, and the diamond powder with the preferred particle size range has a faster sintering speed when sintering, and because more diamond powder falls into the matrix holes 7, the sintered diamond powder can be more effectively extended into the matrix holes 7, and the second protruding structure 12 formed by sintering can be more fully compacted, increasing the contact area between the second protruding structure 12 and the matrix holes 7, thereby further increasing the contact area between the matrix 1 and the diamond layer 2.

[0059] The present application provides a preferred processing method of a diamond composite sheet, which comprises the following steps:

[0060] A) A picosecond green laser is used to emit laser with a laser power of between 80-120 J, and the single-point continuous light-emitting time is 20-30 seconds, and a plurality of matrix holes 7 with a spacing of 2mm*3mm are formed on the matrix composite surface 3 of a tungsten carbide matrix with a diameter of 16mm, and the plurality of matrix holes 7 are arranged in an array to form a matrix hole array, and the diameter of the matrix hole 7 is controlled to be between 0.5mm-1.5mm, and the depth of the matrix hole 7 is controlled to be between 1-3mm.

[0061] B) The mixed raw materials for forming the diamond layer 2 are first filled into the matrix holes 7, and then the matrix 1 is placed on a micro-vibration device to vibrate, so that the mixed raw materials in the matrix holes 7 fall into the matrix holes 7, and then the mixed raw materials are filled onto the matrix composite surface 3 and shaken evenly by the micro-vibration device, wherein the mixed raw materials include diamond powder and a binder, the binder is cobalt, and the particle size of the diamond powder is controlled to be between 10-100 microns.

[0062] C) The temperature is controlled to be between 1300-1500℃, and the pressure is controlled to be between 5.5-8Gpa, so that the mixed raw materials are sintered to form the diamond layer 2.

[0063] In step A of the preferred processing method of the diamond composite sheet, a plurality of matrix holes 7 with a diameter of 0.5mm-1.5mm are processed on a tungsten carbide matrix with a diameter of 16mm with a spacing of 2mm-3mm, and the number of matrix holes 7 on the matrix composite surface 3 of this embodiment is more appropriate, which can greatly improve the interfacial bonding strength between the matrix 1 and the diamond layer 2 while meeting the structural strength of the matrix 1 itself, and the matrix 1 is made of tungsten carbide, so that the transition between the matrix 1 and the diamond layer 2 is better.

[0064] In step B of the preferred method for processing the diamond compact, the diamond powder falling on the substrate composite surface, especially the diamond powder falling near the substrate hole 7, is further dropped into the substrate hole 7 by the vibration of the micro-vibrator and the control of the particle size of the diamond powder between 10-100 microns, thereby increasing the amount of diamond powder in the substrate hole 7, and after sintering in step C, the second protruding structure 12 formed by sintering can fully fill the substrate hole 7, and the contact area between the second protruding structure 12 and the substrate hole 7 is larger.

[0065] In step C of the preferred method for processing the diamond compact, the mixed raw materials in the substrate hole 7 are sintered at a temperature of 1300-1500°C and a pressure of 5.5-8 Gpa to form the diamond layer 2, and the array of several second protruding structures 12 are formed on the diamond layer composite surface 4 of the diamond layer 2, and the array of several second protruding structures 12 are implanted into the substrate 1. On the one hand, the second protruding structure 12 implanted into the substrate 1 can contact the well wall of the substrate hole 7, increasing the contact area between the substrate 1 and the diamond layer 2, and on the other hand, due to the depth of the substrate hole 7 being greater than the depth of the groove structure 6, the height of the second protruding structure 12 is greater than the height of the first protruding structure 5, thereby extending the length of the bonding interface between the substrate 1 and the diamond layer 2 in the axial direction of the diamond layer through the second protruding structure 12 and the substrate hole 7, effectively improving the interface bonding strength between the substrate 1 and the diamond layer 2, reducing the interface residual stress between the substrate 1 and the diamond layer 2, and enhancing the ability of the diamond compact to resist external impact.

[0066] From the above description, it can be seen that the present application has the following advantages: first, on the basis of forming the groove structure 6 and / or the first protrusion structure 5 along the radial direction of the substrate 1 on the substrate composite surface 3, the present application further forms a plurality of substrate holes 7 along the axial direction of the substrate 1 on the substrate composite surface 3. In addition to being able to increase the contact area between the substrate 1 and the diamond layer 2 as the groove structure 6 and the first protrusion structure 5, the substrate holes 7 can also prolong the length of the bonding interface between the substrate 1 and the diamond layer 2 in the axial direction of the diamond composite sheet, effectively improve the interfacial bonding strength between the substrate 1 and the diamond layer 2, reduce the interfacial residual stress between the substrate 1 and the diamond layer 2, and enhance the ability of the diamond composite sheet to resist external impact; second, the diameter of the substrate holes 7 is controlled to be between 0.5mm and 1.5mm, and the hole spacing of the substrate holes 7 is controlled to be between two and three times the diameter of the substrate holes 7. Under the condition of meeting the structural strength of the substrate 1 itself, the number of substrate holes 7 on the substrate composite surface 3 is ensured, thereby ensuring the structural strength of the second connecting structure and the interfacial bonding strength between the substrate 1 and the diamond layer 2; third, the array of a plurality of substrate holes effectively improves the uniformity of pressure dispersion and avoids pressure concentration, thereby further improving the service life of the diamond composite sheet; fourth, the substrate is made of a silicon carbide hard alloy substrate, and the silicon carbide hard alloy substrate has good transition in combination with the diamond layer; and fifth, the processing method of the diamond composite sheet of the present application uses a micro-vibrator to vibrate the diamond powder near the substrate holes 7, so that the diamond powder falls into the substrate holes 7, and the diamond powder with a particle size of 10-100 microns is used, which facilitates the diamond powder to fall into the substrate holes 7, so that the second protrusion structure 12 fully contacts the substrate holes 7 after sintering, and the base area of the substrate 1 and the diamond layer 2 is further improved.

[0067] In addition, it should be noted that the preferred embodiments of the present application are described in detail above in combination with the drawings, but it should be noted that the present application is not limited to the specific details in the above embodiments, and various simple modifications can be made to the technical solutions of the present application within the technical concept of the present application, and these simple modifications all belong to the protection scope of the present application. In particular, as long as there is no structural conflict, each technical feature mentioned in each embodiment can be combined in any way.

Claims

1. A polycrystalline diamond compact comprising, The substrate (1) and the diamond layer (2) are provided on one side of the substrate (1), the surface of the substrate (1) and the diamond layer (2) opposite to each other are the substrate complex surface (3) and the diamond layer complex surface (4) respectively, the substrate complex surface (3) and the diamond layer complex surface (4) are matched by a plurality of first protruding structures (5) and a plurality of groove structures (6) matched with each other, the first protruding structure (5) and the groove structure (6) are formed on at least one of the substrate complex surface (3) and the diamond layer complex surface (4) respectively, the substrate complex surface (3) is further provided with a plurality of substrate holes (7), the diamond layer (2) is provided with a second protruding structure (12) matched with the substrate hole (7), the depth of the substrate hole (7) is greater than the depth of the groove structure (6), the diameter of the substrate hole (7) is 0.5-1.5mm, the depth is 1-3mm, the distance between two adjacent substrate holes (7) is greater than or equal to twice the diameter of the substrate hole (7) and less than or equal to three times the diameter of the substrate hole (7).

2. The diamond compact of claim 1, wherein, The substrate hole (7) is perpendicular to the substrate complex surface (3).

3. The diamond compact of claim 1, wherein, The plurality of substrate holes (7) are arranged in an array to form a substrate hole array.

4. The diamond compact of claim 3, wherein, The substrate (1) is a cylindrical structure.

5. The diamond compact of claim 4, wherein, The substrate hole array is a ring array (8).

6. The diamond compact of claim 5, wherein, The first protruding structure (5) is arranged on the substrate complex surface (3), and the groove structure (6) is arranged on the diamond layer complex surface (4).

7. The diamond compact of claim 6, wherein, The plurality of substrate holes (7) arranged in the ring array (8) are distributed outward from the center position of the substrate complex surface (3) in the radial direction to divide the substrate complex surface (3) into a plurality of fan-shaped regions, at least one first protruding structure (5) is arranged in each fan-shaped region, and the length direction of the first protruding structure (5) extends along the radial direction of the substrate complex surface (3).

8. The diamond compact of claim 4, wherein, The substrate hole array is a semicircular array (9).

9. The diamond compact of claim 8, wherein, The plurality of substrate holes (7) are arranged in an array to form two semicircular arrays (9), and the two semicircular arrays (9) are symmetrically arranged with the diameter of the substrate complex surface (3) as the axis of symmetry.

10. The diamond compact of claim 9, wherein, Each group of the first protruding structures (5) is arranged with a plurality of first protruding structures (5), and the first protruding structures (5) in adjacent two groups are arranged at intervals, and the distance between two adjacent first protruding structures (5) in each group is equal.

11. The diamond compact of any of claims 5-10, wherein, The groove structure (6) is a ring groove, a plurality of ring grooves are distributed outward from the center position of the substrate complex surface (3) in the radial direction, an annular surface (11) is formed between two adjacent ring grooves, a plurality of substrate holes (7) are arranged in the annular surface (11) and distributed around the ring groove.

12. A method of machining a diamond compact for machining a diamond compact according to any one of claims 1 to 11, characterized in that, The method comprises the following steps: A) processing a plurality of substrate holes (7) and processing the first protruding structure (5) and / or groove structure (6) on one side of the substrate (1); B) filling mixed raw materials for forming a diamond layer (2) on the side and then sintering.

13. The method of claim 12, wherein, The step of filling the mixed raw material for forming the diamond layer (2) into the side surface includes a step of filling the mixed raw material into the base hole (7) and a step of filling the mixed raw material into the side surface.

14. The method of claim 12, wherein, The mixed raw material contains a binder and diamond powder.

15. The method of claim 14, wherein, The diamond powder has a particle size of 10-100 μm.

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