Method of joining a polycrystalline diamond compact to a metal body and related joined structures formed thereby

Abstract

An industrial tool (100) includes a tool body (102) having a pocket (114). The pocket has an inside surface (330). The tool body further includes a polycrystalline diamond compact ("PDC") having a polycrystalline diamond table (112) and a substrate. The PDC is disposed at least partially within the pocket. The tool includes surface structures protruding from at least one or both of an outside surface of the PDC or the inside surface of the pocket. The PDC is secured to the tool body via the surface structures.

Description

[0001] METHOD OF JOINING A POLYCRYSTALLINE DIAMOND COMPACT TO A METAL BODY AND RELATED JOINED STRUCTURES FORMED THEREBY

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application Serial No. 63 / 733,032, filed December 12, 2024.

[0004] TECHNICAL FIELD

[0005] This disclosure relates generally to methods of joining poly crystalline diamond compacts, such as poly crystalline diamond compact cutting elements for earth-boring tools, to metal bodies, such as steel bodies of earth-boring tools.

[0006] BACKGROUND

[0007] Brazing is widely used to join materials by way of a filler material that melts upon heating and coats the surface of materials being joined, creating a bond upon cooling and solidification of the braze material. A suitable filler material wets the surfaces of the materials being joined and allows the materials to be joined without changing the physical properties of the materials. Braze materials generally melt at a low temperature in comparison to the melting temperature of the materials being joined. During a brazing process, heating and cooling of the materials may take place in an open atmosphere or in a controlled atmosphere furnace or vacuum furnace. Braze materials are often based on metals such as Ag, Au, Cu, Ni, Ti. Pd. Pt, Cr, and alloys thereof. Braze base materials may also include fractions of a wide variety of other elements that are added to vary the properties (e.g., melting point, strength, hardness, etc.) of the resulting alloy. Brazing can be used to join similar or dissimilar materials, e g., metals to metals, ceramics to ceramics, and metals to ceramics. The metal may be a hard metal.

[0008] Typically, in a brazing process, a filler metal or alloy is heated to a melting temperature above 425°C (800°F) and distributed between two or more close-fitting parts by direct placement of the filler material or draw n into the interface between the tw o parts by capillary action. At the liquid temperature of a braze material, the molten filler metal interacts with the surface of the base metal, cooling to form a strong, sealed joint. In a brazed joint, the joint becomes a sandwich of different layers, each metallurgically linked to the adjacent layers. Common braze joints may be less strong than the parent materials due either to the inherent lower yield strength of the braze alloy or to the low fracture toughness of intermetallic components. Alternatively, brazed joints in some types of automotive sheet metal are substantially stronger than the surrounding strength of the sheet metal.

[0009] If a silver alloy is used, the brazing can be referred to as silver brazing. These silver alloys may have many different percentages of silver and other compounds such as copper, zinc, and cadmium. Generally, silver brazing requires a gap of between approximately 50 pm to 130 pm (0.002 inch to 0.005 inch) for proper capillary action during the joining of members.

[0010] In braze welding, the use of a bronze or brass filler rod coated with flux, together with an oxyacetylene torch are typically used to join pieces of steel. Braze welding does not rely on capillary attraction. Braze welding takes place at the melting temperature of the filler (about 870°C to 980°C or about 1600°F to 1800°F for bronze alloys) which is lower than the melting point of the base material (about 1600°C or 2900°F for mild steel alloys).

[0011] Braze welding has advantages over fusion welding as it allows the joining of dissimilar metals, minimizes heat distortion, and reduces extensive preheating of the parts. A side effect of braze welding is that stored-up stresses in the parts being joined may be significantly reduced in contrast to that of fusion welding. However, braze welded joints have the disadvantages of loss of strength when subjected to high temperatures.

[0012] While given two joints with the same geometry, brazed joints are generally not as strong as welded joints, although a properly designed and executed brazed joint can be stronger than the parent metal. By careful matching of joint geometry to the forces acting on the joint and properly maintaining clearance between two mating parts being joined, the brazed joint can be a strong joint.

[0013] In the oil and gas industry, poly crystalline diamond compacts (PDCs) are widely employed as cutting elements in earth-boring tools such as rotary drill bits, as bearing elements in moving parts such as rotors and stators, or as wear-resistant inserts in downhole tools. These PDCs, which may or may not be bonded to a substrate (such as a ceramic particle / metal matrix composite material (e.g., iron- or cobalt-cemented tungsten carbide)), are typically joined to a metal (e g., steel) body of a downhole tool, such as a drill bit, a carrier body of a bearing element, a rotor, a stator, etc., by using brazing. In a non-limiting embodiment, the substrate is also referred to herein as a tungsten carbide substrate. Currently, failures are often encountered that are related to improper brazing of PDCs to a steel body. The PDCs detach inside pockets in the steel body of the tool under applied loads, start to rotate, crack, chip, etc., and cause detrimental damage to the other components of the bottom hole assembly (BHA).

[0014] Joining PDCs to a steel body is challenging. Current brazing processes are commonly carried out at temperatures around 700°C, which may cause damage to the poly crystalline diamond, and are challenging processes.

[0015] It is known that tungsten carbide surfaces of the PDC substrates do not wet properly, since only the cobalt binder phase bonds strongly with the braze material, whereas a majority of the surface area is composed of the tungsten carbide ceramic phase rather than the cobalt phase.

[0016] The brazing process on a closed steel pocket is not ideal, and impurities and residues from cleaning process cannot be fully removed prior to and during the brazing process. As a result, the braze joint of the PDC with steel is relatively weak compared with braze joints between two steel bodies, for example.

[0017] Alternative processes such as adhesive bonding do not result in proper bonding strength to resist shear forces during bearing application. Furthermore, many adhesives, due to their organic chemical nature, show a severe drop in adhesion strength above 80°C.

[0018] DISCLOSURE

[0019] According to one embodiment of the disclosure, an industrial tool includes a tool body having a pocket. The pocket has an inside surface. The tool body further includes a poly cry stall me diamond compact (“PDC’') having a poly crystalline diamond table and a substrate. The PDC is disposed at least partially within the pocket. The tool includes surface structures protruding from at least one or both of an outside surface of the PDC or the inside surface of the pocket. The PDC is secured to the tool body via the surface structures.

[0020] In one embodiment, a method of bonding a PDC to a tool body is provided. The method includes forming a pocket in the tool body. The pocket has an inside surface. The method further includes forming protruding surface structures over at least one or both of an outside surface of the PDC or the inside surface of the pocket. The PDC is inserted at least partially within the pocket, and the PDC is bonded to the tool via the protruding surface structures. In one embodiment, a method of bonding a PDC to a body formed of a metal or metal alloy includes plating a bonding surface of one or both of the PDC or the body with a metal or metal alloy and brazing the PDC to the body with a braze filler metal.

[0021] BRIEF DESCRIPTION OF THE DRAWINGS

[0022] For a detailed understanding of the disclosure, reference should be made to the following detailed description, taken in conjunction with the accompanying drawings, in which like elements have generally been designated with like numerals.

[0023] FIG. 1 is a perspective view of an earth-boring rotary drill bit having PDCs attached to a body of the drill bit using methods in accordance with the present disclosure.

[0024] FIGS. 2A, 2B, and 2C are perspective views of bearing assemblies having PDCs attached to a body of the bearing assemblies using methods in accordance with the present disclosure.

[0025] FIGS. 3A, 3B, and 3C are simplified, cross-sectional views of a PDC attached within a pocket of a body using methods in accordance with the present disclosure.

[0026] FIGS. 4A and 4B are simplified, cross-sectional views of a PDC within a pocket of a body where the PDC and / or pocket includes surface structures according to embodiments of the present disclosure.

[0027] FIG. 5A, 5B, and 5C are simplified, cross-sectional views of a PDC within a pocket of a body where the PDC and / or the pocket include plating with surface structures according to embodiments of the present disclosure.

[0028] FIG. 6 is a simplified, cross-sectional view of a PDC within a pocket of a body and a surface protection ring covering a bonding interface between the PDC and pocket according to embodiments of the present disclosure.

[0029] FIG. 7 is a simplified, cross-sectional view of a PDC and a connecting element within a pocket of a body according to embodiments of the present disclosure.

[0030] FIG. 8 is a simplified, cross-sectional view of a PDC within a pocket of a body where the PDC and pocket have nonrectangular cross-sectional profiles according to embodiments of the present disclosure. MODE(S) FOR CARRYING OUT THE INVENTION

[0031] The illustrations presented herein are not actual views of any particular PDC or body, or any component thereof, but are merely idealized representations, which are employed to describe embodiments of the invention.

[0032] FIG. 1 shows a drill bit 100 incorporating a plurality of poly crystalline diamond compact (“PDC’) cutting elements attached to a bit body 102 using processes as described herein in accordance with embodiments of the present disclosure. The drill bit 100 is configured as a fixed cutter earth-boring rotary drill bit also known in the art as a “drag bit.” The bit body 102 of the drill bit 100 may be composed of a metal or metal alloy, such as steel. The drill bit 100 includes a shank 106 having a conventional male threaded pin 104 configured to API standards and adapted for connection to a component of a drill string. Blades 108 of the bit body 102 have mounted thereon a plurality’ of PDC cutting elements 110, each comprising a poly crystalline diamond table 112 formed on a hard metal substrate, such as a tungsten carbide substrate. The PDC cutting elements 110 are secured in respective cutter pockets 114 using embodiments of methods of the present disclosure, as descnbed in further detail hereinbelow. The PDC cutting elements 1 10 are positioned to cut a subterranean formation being drilled when the drill bit 100 is rotated under weighton-bit (WOB) in a bore hole. The bit body 102 may include gage trimmers 118 including the aforementioned polycrystalline diamond tables 112 configured with a flat edge aligned parallel to the rotational axis 120 of the drill bit to trim and hold the gage diameter of the bore hole, and gage pads 116 on the gage which contact the walls of the bore hole to maintain the hole diameter and stabilize the drill bit 100 in the hole.

[0033] In an alternative application, PDCs are used in bearings utilized in earth-boring tools or devices (downhole tools), such as drill strings or other applications in highly abrasive environments, e.g. stirrers or mixers in the food industry, for paint blenders, or the like. PDC bearing assemblies can be configured in various geometries, including thrust and radial bearings (male and female). For example, a male radial bearing can be positioned within a female radial bearing, with a thrust bearing positioned between the two to accommodate axial loads. FIGS. 2A, 2B, and 2C illustrate exemplary bearing components of PDC bearing assemblies. In FIG. 2A, a male radial bearing assembly 200a comprises a male radial bearing carrier body 202a with a central bore 203a along a longitudinal axis 204a of the male radial bearing carrier body 202a. A plurality' of first PDC bearing elements 210a may be affixed within male radial bearing insert pockets 214a of the male radial bearing carrier body 202a. The first PDC bearing elements 210a include first poly crystalline diamond tables 212a with first bearing surfaces 213a. The first PDC bearing elements 210a may be bonded within the male radial bearing insert pockets 214a to the male radial bearing carrier body 202a by the methods disclosed herein.

[0034] In FIG. 2B, a female radial bearing assembly 200b comprises a female radial bearing carrier body 202b with a central bore 203b along a longitudinal axis 204b of the female radial bearing carrier body 202b. Second PDC bearing elements 210b are affixed within female radial bearing insert pockets 214b on an inside surface of the female radial bearing carrier body 202b and bonded to the female radial bearing carrier body 202b as explained herein. The second PDC bearing elements 210b include second polycrystalline diamond tables 212b with second bearing surfaces 213b. The first bearing surface 213a (FIG 2A) and the second bearing surface 213b face each other and slide on each other when operated after assembly to provide a radial bearing assembly. The male radial bearing assembly 200a (FIG. 2A) and the female radial bearing assembly 200b together form a radial bearing. The bearing surfaces 213a. 213b referred to in this application are superhard bearing surfaces.

[0035] In FIG. 2C, a thrust bearing assembly 200c comprises a first thrust bearing carrier body 202c. First thrust bearing PDC elements 210c are affixed within first thrust bearing insert pockets 214c on the first thrust bearing carrier body 202c and bonded to the first thrust bearing carrier body 202c as explained herein. The first thrust bearing PDC elements 210c include poly crystalline diamond tables 212c with thrust bearing surfaces 213c. A thrust bearing is completed by a second thrust bearing assembly (not shown), which is similar to the first thrust bearing assembly 200c. The second thrust bearing assembly comprises a second thrust bearing carrier body and second thrust bearing PDC elements affixed within second thrust bearing insert pockets on the second thrust bearing carrier body and bonded to the second thrust bearing carrier body as explained herein. The second thrust bearing PDC elements include polycrystalline diamond tables with thrust bearing surfaces. The first thrust bearing surface 213c and the second thrust bearing surface (not shown) face each other and slide on each other when assembled to provide a thrust bearing assembly. The first thrust bearing assembly 200c and the second thrust bearing assembly (not shown) together form a thrust bearing. A PDC element in this application may also be referred to as PDC insert. The radial bearing and the thrust bearing may be used in a rotary steering assembly in a downhole string or a bottom hole assembly (BHA) in a drilling operation to allow relative rotation between a drive shaft and a non-rotating or slowly rotating sleeve.

[0036] As mentioned above, a PDC cutting element 110 may typically be bonded within the cutter pocket 114 of the bit body 102 via brazing (see FIG. 1). Also as mentioned above, PDC bearing elements 210a, 210b, 210c may typically be bonded within a radial or thrust bearing insert pocket 214a, 214b, 214c of a male or female radial bearing carrier body 202a, 202b, or a thrust bearing carrier body 202c (FIGS. 2A-2C). Each PDC cutting element 110 or PDC bearing elements 210a, 210b, 210c comprises a poly cry stalline diamond table 112, 212a, 212b, 212c on a tungsten carbide substrate. For example, a filler metal or metal alloy is heated to a melting temperature (e.g., above 425°C) and is distributed at an interface between the cutter pocket 114 or the radial or thrust bearing insert pocket 214a, 214b, 214c and the tungsten carbide substrate of the PDC cutting element 110 or the PDC bearing elements 210a, 210b, 210c by direct placement of the braze filler metal or by drawing the braze filler metal into the interface by capillary’ action. As mentioned above Joining the PDC cutting element 110 or the PDC bearing elements 210a, 210b, 210c to the cutter pocket 114 or the radial or thrust bearing insert pocket 214a, 214b, 214c via brazing may result in PDC cutting elements 110 that are not bonded to the cutter pockets 114 or the radial or thrust bearing insert pocket 214a, 214b, 214c with sufficient strength. This can result in the rotation of the PDC cutting element 110 or the PDC bearing elements 210a, 210b, 210c within the cutter pocket 1 14 or the radial or thrust bearing insert pocket 214a, 214b, 214c and / or the PDC cutting element 110 or the PDC bearing elements 210a, 210b, 210c falling out of the cutter pocket 114 or the radial or thrust bearing insert pocket 214a, 214b, 214c. This may result in inefficient operation of the drill bit 100 and / or damage to the drill bit 100 or in inefficient operation of the male radial bearing assembly 200a and female radial bearing assembly’ 200b or the thrust bearing assembly 200c.

[0037] FIG. 3 A shows a simplified, cross-sectional view of a PDC 310 within a pocket 314 in a tool body 302. according to embodiments of the present disclosure. The PDC 310 may be similar to either the PDC cutting elements 110 described above with reference to FIG. 1 or the PDC bearing elements 210a, 210b, 210c described above with reference to FIGS. 2A-2C. The tool body 302 may be similar to the bit body 102 or the carrier bodies 202a, 202b. 202c described above. In FIG. 3A, a plating 326 is formed onto the tungsten carbide substrate 322 of the PDC 310. The plating 326 may be formed onto the tungsten carbide substrate 322 via any suitable process such as electroplating. The plating 326 may be formed onto the whole surface of the tungsten carbide substrate 322 or only on a portion of the tungsten carbide substrate 322. The plating 326 may be a conductive metal or metal alloy and may include such metals as, but not limited to, titanium, nickel, cobalt, iron, silver, or copper. In some embodiments, the plating 326 may be formed via an electroless plating process via a physical vapor deposition process (PVD) (such as sputtering process). The plating 326 may have a thickness of, for example, from about 5 to 30 microns. In some embodiments, the plating 326 may have a thickness of about 10 to 20 microns.

[0038] The plating 326 on the tungsten carbide substrate 322 of the PDC 310 functionalizes an outside surface 336 of the tungsten carbide substrate 322 and may provide a better interface for the braze filler metal 324 to bond the PDC 310 into the pocket 314 of the tool body 302, relative to the tungsten carbide material of the substrate 322. For example, the plating 326 may improve wettability of the tungsten carbide substrate 322 of the PDC 310. The PDC 310 may be bonded into the pocket 314 by plating the outer surface of at least a portion of the tungsten carbide substrate 322 and then bonding the PDC 310 into the pocket 314 via brazing. To ensure proper bonding, the plating 326 on the tungsten carbide substrate 322 may be formed on at least a portion of the outside surface 336 of the substrate 322 that is supposed to be wetted by the braze filler metal 324. This may include a portion or all of a lateral outside surface 335 of the outside surface 336 of the tungsten carbide substrate 322 and a portion or all of a bottom outside surface 337 of the outside surface 336 of the tungsten carbide substrate 322 being plated with the plating 326. The braze filler metal 324 joins the PDC 310 to the pocket 314 via the plating 326 and by directly contacting the pocket 314. The polycrystalline diamond table 312 comprises a lateral outside surface 315 and an upper outside surface. The upper outside surface is the bearing surface 313 of the PDC 310 or the PDC table 312. The plating 326 on the outside surface 336 of the tungsten carbide substrate 322 ends below the interface 317 between the lateral outside surface 315 of the polycrystalline diamond table 312 and the outside surface 326 of the tungsten carbide substrate 322. In an alternative embodiment, the plating 326 reaches up to the interface 317 betw een the lateral outside surface 315 of the polycrystalline diamond table 312 and the outside surface 326 of the tungsten carbide substrate 322. In this disclosure, the upper end 319 of the PDC 310 is the end with the PDC table 312 and the lower end or bottom end 320 of the PDC 310 is formed by the tungsten carbide substrate 322 and is opposite the bearing surface 313.

[0039] FIG. 3B shows a simplified, cross-sectional view of a PDC 310 within a pocket 314 in a tool body 302, according to embodiments of the present disclosure. The PDC 310 may be similar to either the PDC cutting elements 110 described above with reference to FIG. 1 or the PDC bearing elements 210a, 210b, 210c described above with reference to FIGS. 2A-2C. The tool body 302 may be similar to the bit body 102 or the earner bodies 202a, 202b, 202c described above. As shown in FIG. 3B, a plating 328 may be formed on an inside surface 330 of the pocket 314. Similar to the plating 326, the plating 328 may further strengthen the bond formed by the braze filler metal 324 at the interface between the PDC 310 and the pocket 314. The braze filler metal 324 joins the PDC 310 to the pocket 314 via the plating 328 and by directly contacting an outside surface 336 of the substrate 322 of the PDC 310. To ensure proper bonding, the plating 328 on the inside surface 330 of the pocket 314 in the tool body 302 may be formed on the inside surface 330 of the pocket 314 that is supposed to be wetted by the braze filler metal 324. For example, a portion or all of a lateral inside surface 331 of the pocket 314 and a portion or all of a bottom inside surface 333 of the pocket 314 is plated.

[0040] The plating 328 may be similar to plating 326 in that it may be formed by an electroplating process, an electroless plating process, or PVD. The plating 328 may similarly be formed from a conductive metal or metal alloy such as, but not limited to. nickel, cobalt, iron, or copper. The plating 328 may have a thickness of, for example from about 5 to 30 microns. In some embodiments, the plating 328 may have a thickness of about 10 to 20 microns. In some embodiments the plating 326 and 328 may be different and may be selected based on material properties of the substrate 322 and the material of the tool body 302.

[0041] In some embodiments, both the plating 326 on the outside surface 336 of the PDC 310 and the plating 328 on the inside surface 330 of the pocket 314 may be used simultaneously. FIG. 3C shows a simplified, cross-sectional view of a PDC 310 within a pocket 314 in a tool body 302. according to additional embodiments of the present disclosure. The PDC 310 may be similar to either the PDC cutting elements 1 10 described above with reference to FIG. 1 or the PDC bearing elements 210a, 210b, 210c described above with reference to FIGS. 2A-2C. The tool body 302 may be similar to the bit body 102 or the carrier bodies 202a. 202b, 202c described above. In FIG. 3C, the plating 326 (e.g., a first plating) is formed on the outside surface 336 of the PDC 310 and the plating 328 (e.g.. a second plating) is formed on the inside surface 330 of the pocket 314 prior to joining the PDC 310 to the pocket 314 via brazing with a braze filler metal 324. With the plating 326, 328 on the PDC 310 and within the pocket 314, respectively, the strength of a bonding interface between the PDC 310 and the pocket 314 may be enhanced. The brazing may be performed by heating the tool body 302 and the PDC 310 up to the melting temperature of the braze filler metal 324.

[0042] FIG. 4A shows a simplified, cross-sectional view of a PDC 410 within a pocket 414 in the tool body 402 according to embodiments of the present disclosure. The PDC 410 may be similar to either the PDC cutting elements 110 described above with reference to FIG. 1 or the PDC bearing elements 210a. 210b, 210c described above with reference to FIGS. 2A-2C. The tool body 402 may be similar to the bit body 102 or the earner bodies 202a, 202b, 202c described above. As shown in FIG. 4 A, the PDC 410 may be joined to the tool body 402 within the pocket 414 by way of surface structures 434 formed on the outside surface 436 of the PDC 410. The surface structures 434 formed on the outside surface 436 of the PDC 410 protrude from the outside surface 436. The surface structures 434 protrude, at least partially, in a direction normal to the outside surface 436 of the PDC 410. A gap 439 may exist between the outside surface 436 of the PDC 410 and an inside surface 430 of the pocket 414. The gap 439 may have a width of about 0.02 mm to 0. 1 mm, about 0.05 m to 0. 1 mm, about 0.1 mm to 0.2 mm. or about 0. 1 mm to 0.5 mm. For example, the surface structures 434 may be formed directly on the outside surfaces 436 of the tungsten carbide substrate 422. For example, the surface structures 434 may be formed on a portion or all of a lateral outside surface 435 of the substrate 422 and a portion or all of a bottom outside surface 437 of the substrate 422. The PDC 410 may then be inserted into the pocket 414 under pressure and, optionally, elevated temperature to form a bonded interface between the PDC 410 and the pocket 414 by creating a bond between the surface structures 434 and the inside surface 430 of the pocket 414.

[0043] FIG. 4B shows a simplified, cross-sectional view of a PDC 410 within a pocket 414 of a tool body 402. according to embodiments of the present disclosure. As shown in FIG. 4B, the PDC 410 may be joined to the tool body 402 within the pocket 414 by way of surface structures formed on the outside surface 436 of the PDC 410 and on inside surfaces 430 of the pocket 414. For example, first surface structures 432 may be formed directly on the inside surfaces 430 of the pocket 414, and second surface structures 434 may be formed directly on the outside surfaces 436 of the tungsten carbide substrate 422 of the PDC 410. The first surface structures 432 formed on the inside surface 430 of the pocket 414 protrude from the inside surface 430. The first surface structures 432 protrude, at least partially, in a direction normal to the inside surface 430 of the pocket 414. The second surface structures 434 formed on the outside surface 436 of the PDC 410 protrude from the outside surface 436. The second surface structures 434 protrude, at least partially, in a direction normal to the outside surface 436 of the PDC 410. The first surface structures 432 and the second surface structures 434 are, at least partially, parallel to each other. For example, the first surface structures 432 may be formed on a portion or all of a lateral inside surface 431 of the pocket 414 and a portion or all of a bottom inside surface 433 of the pocket 414. Second surface structures 434 may be formed on a portion or all of a lateral outside surface 435 of the substrate 422 and a portion or all of a bottom outside surface 437 of the substrate 422. In one embodiment, the gap 439 between the lateral surfaces 435, 431 may be the same as the gap between the bottom surfaces 437, 433. In one more embodiment the gap between the lateral surfaces 435, 431 is different than the gap between the bottom surfaces 437, 433. The PDC 410 may then be inserted into the pocket 414 under pressure and, optionally, elevated temperature to form a bonded interface between the PDC 410 and the pocket 414.

[0044] In some embodiments, the first surface structures 432 and the second surface structures 434 may be formed on the surfaces to be bonded (e.g., the inside surfaces 430 of the pocket 414 and the outside surfaces 436 of the tungsten carbide substrate 422 of the PDC 410) using the processes disclosed in any of the following: U.S. Patent Application Publication No. 2024 / 0191383 Al, published June 13, 2024, and titled “Device and Method for the User-Friendly and Reliable Galvanic Growth of a Plurality of Nanow ires." U.S. Patent Application Publication No. 2024 / 0141542 Al, published May 2, 2024, and titled “Growth of Nanowires,” U.S. Patent Application Publication No. 2024 / 0141531 Al, published May 2, 2024, and titled “Galvanic Growth of Nanowires on a Substrate,” U.S. Patent Application Publication No. 2024 / 0344223 Al, published October 17, 2024, and titled “Growth of Nanowires,” and U.S. Patent Application Publication No. 2024 / 0304581 Al , published September 12, 2024, and titled “Coating of Nanowires,” the disclosures of which are incorporated herein in their entireties by this reference.

[0045] After forming the first surface structures 432 and the second surface structures 434 on the surfaces to be bonded, the elements to be bonded (e.g.. the PDC 410 and the tool body 402) are brought into contact with one another. A pressure may be applied on the PDC 410, on the tool body 402, or on both, to compress the first surface structures 432 and the second surface structures 434 on the opposing surfaces to be bonded together. For example, a pressure of from 5 MPa to 30 MPa may be applied between the elements to be bonded. Optionally, ultrasonic vibrations may also be applied to the elements to be bonded while the first surface structures 432 and the second surface structures 434 are in contact with one another, again, with or without applied pressure. The bonding process may be carried out at room temperature, or it may be carried out at elevated temperatures. For example, the bonding process may be carried out at an elevated temperature between 30°C and 500°C, more particularly between 100°C and 350°C, or even more particularly between 150°C and 250°C.

[0046] In some embodiments, the first surface structures 432 and the second surface structures 434 are formed as wires. The first surface structures 432 may extend from the inside surfaces 430 of the pocket 414, while the second surface structures 434 extend from the outside surfaces 436 of the tungsten carbide substrate 422. The wires may be termed micro wires. In some embodiments, the wires may have a length of about 10 microns to about 100 microns and a width of about 1 micron to about 20 microns. In some embodiments the wires may have a length of about 5 microns to 50 microns and a width of 1 micron to 10 microns. In some embodiments, the wires may be termed nanowires and may have a length of about 500 nm to about 1 micron and a width of about 100 nm to 500 nm. The density of wires on the inside surface 430 and / or outside surface 436 may be about 50 wires per 20 square microns, or 2500 wires per 400 square microns.

[0047] In some embodiments, the wires of the first surface structures 432 and / or the second surface structures 434 may comprise branched endings and / or structures formed at ends thereof such as loop-, hook-, or disc-like structures, scales, or other shaped-structures. In some examples, the first surface structures 432 and the second surface structures 434 may interact during bonding and form a connection between the respective structures. In some embodiments, bond strength may be improved by thermally driven sintering-like processes conducted at relatively low temperatures (e.g., about 200°C to 400° or about 200°C to 700°C). In some embodiments the first surface structures 432 may be welded to the second surface structures 434 by entangling the surface structures 432, 434 by physically bringing the surface structures 432, 434 together and applying pressure. In some embodiments, this happens without warming up the surface structures. The surface structures 432 and / or 434 protrude from the outside surface 436 of the substrate 422 and / or the inside surface 430 of the pocket 414. The surface structures 432 and 434 are applied to surfaces 430 and / or 436 created by a distinct manufacturing process. The surface structures 432, 434 are different from a surface roughness. A process to apply the surface structures 432, 434 may include placing on the surface 436 and / or 430 a matrix (e.g. PTFT foil) with openings and depositing material through the openings on the surface 436 and / or 430 by using a depositing method such as for example electrochemical galvanization. The surface structures 432, 434 may be made from copper, gold, nickel, silver, zinc, or other suitable materials. The surface structures 432, 434 have a distinct shape as mentioned earlier. The surface structures may protrude from the surface 436 and / or 430 by about 2.5 microns to 100 microns, about 5 microns to 100 microns, or about 10 microns to 50 microns.

[0048] In FIG. 4A, the second surface structures 434 are formed on the outside surface 436 of the substrate 422 of the PDC 410 while in FIG. 4B, second surface structures 434 are formed on the outside surface 436 of the substrate 422 and first surface structures 432 are formed on the inside surface 430 of the pocket 414. In some embodiments, the first surface structures 432 are formed on the inside surface 430 of the pocket 414 without the second surface structures 434 formed on the outside surface 436 of the substrate 422.

[0049] FIG. 5 A shows a simplified, cross-sectional view of a PDC 510 within a pocket 514 in a tool body 502. according to embodiments of the present disclosure. The PDC 510 may be similar to either the PDC cutting elements 110 described above with reference to FIG. 1 or the PDC bearing elements 210a, 210b, 210c described above with reference to FIGS. 2A-2C. The tool body 502 may be similar to the bit body 102 or the carrier bodies 202a, 202b. 202c described above. As shown in FIG. 5A, a second plating 527 may be formed on the outside surface 536 of the tungsten carbide substrate 522 as described above with reference to FIG. 3A. The second plating 527 may also be referred to herein as a second structure plating. Second plating surface structures 538 may be formed on the second plating 527. The first surface structures 532 may be formed directly on the inside surface 530 of the pocket 514. When the PDC 510 is inserted into the pocket 514, the second plating surface structures 538 and the first surface structures 532 may form a bonded interface between the PDC 510 and the pocket 514 of the tool body 502.

[0050] FIG. 5B shows a simplified, cross-sectional view of a PDC 510 within a pocket 514 of a tool body 502. according to embodiments of the present disclosure. The PDC 510 may be similar to either the PDC cutting elements 110 described above with reference to FIG. 1 or the PDC bearing elements 210a, 210b, 210c described above with reference to FIGS. 2A-2C. The tool body 502 may be similar to the bit body 102 or the earner bodies 202a, 202b, 202c described above. As shown in FIG. 5B, a first plating 529 may be formed on the inside surfaces 530 of the pocket 514 as described above with reference to FIG. 3B. The first plating 529 may also be referred to herein as first structure plating. First plating surface structures 540 may be formed on the first plating 529. The second surface structures 534 are formed directly on the outside surface 536 of the substrate 522 of the PDC 510. When the PDC 510 is inserted into the pocket 514, the first plating surface structures 540 and the second surface structures 534 may form a bonded interface between the PDC 510 and the pocket 514 of the tool body 502.

[0051] FIG. 5C shows a simplified, cross-sectional view of a PDC 510 within a pocket 514 of a tool body 502, according to embodiments of the present disclosure. The PDC 510 may be similar to either the PDC cutting elements 110 described above with reference to FIG. 1 or the PDC bearing elements 210a, 210b, 210c described above with reference to FIGS. 2A-2C. The tool body 502 may be similar to the bit body 102 or the earner bodies 202a, 202b, 202c described above. As shown in FIG. 5C, both the second plating 527 and the first plating 529 may be formed on the outside surfaces 536 of the tungsten carbide substrate 522 and on the inside surfaces 530 of the pocket 514, respectively. The second plating surface structures 538 may be formed on the second plating 527, and the first plating surface structures 540 may be formed on the first plating 529. When the PDC 510 is inserted into the pocket 514, the second plating surface structures 538 and the first plating surface structures 540 may form a bonded interface between the PDC 510 and the pocket 514 of the tool body 502. The first plating 529 functionalizes the inside surface 530 of the pocket 514 and the second plating 527 functionalizes the outside surface 536 of the tungsten carbide substrate 522. Functionalizing the surfaces 530, 536 facilitates depositing the material of the surface structures 538, 540 and ensures proper bonding of the surface structures 538. 540 to the surfaces the surface structures 538, 540 are built on.

[0052] The platings 527 and 529 used in combination with surface structures can be the same or can be different to the plating 326 and 328 used in combination with a braze filler metal 324 (FIGS. 3A-3C). In some embodiments, the platings 527 and 529 may differ in material and thickness from the material and the thickness of the plating 326 and 328. FIG. 6 shows a simplified, cross-sectional view of a PDC 610 within a pocket 614 in a tool body 602. according to embodiments of the present disclosure. The PDC 610 may be similar to either the PDC cutting elements 110 described above with reference to FIG. 1 or the PDC bearing elements 210a, 210b, 210c described above with reference to FIGS. 2A-2C. The tool body 602 may be similar to the bit body 102 or the carrier bodies 202a, 202b. 202c described above. In some embodiments, the bonded interface formed between the PDC 610 and the pocket 614 with the surface structures, such as those described above with reference to FIGS. 4A-5C, may be protected from an external environment via a surface protection ring 642. The surface protection ring 642 may be formed to contact the outside surface 636 of the PDC 610 and a top edge 644 of the pocket 614 to cover the bonded interface between the PDC 610 and the pocket 614.

[0053] For example, the surface protection ring 642 may protect the first surface structures 632 and the second surface structures 634 from corrosive environments in a wellbore. The first and second surface structures 632, 634 may include large surface areas due to the micrometer or even nanometer dimensions of the surface structures 632. 634. The large surface areas provide a large attack area to corrosive substances (e.g., H2S) that may be present in wellbore fluids that are used in hydrocarbon drilling operations. Temperatures in a wellbore are typically between 50°C and 250°C, which promotes corrosive processes. The surface protection ring 642 protects surface structures 632 and 634 from contact with wellbore fluids (e.g., from fluid ingress). The surface protection ring 642 seals the upper end (close to an interface between the substrate 622 and the poly crystalline diamond table 612) of a gap 639 defined by the distance between the inside surface 630 of the pocket 614 and the outside surface 636 of the PDC 610.

[0054] The surface protection ring 642 may be formed from any suitable material to provide resistance to wear caused by the environment of use of the PDC 610. For example, the surface protection ring 642 may be formed from a metallic material (such as a brazing material (e.g., a silver brazing)), an epoxy, a polymeric material, a rubber or synthetic rubber material, an elastomer, a thermoplastic, or the like.

[0055] The surface protection ring 642 may be vulcanized to the outside surface 636 of the PDC 610 and to the top edge 644 or a top surface 641 of the tool body 602. In some embodiments, the surface protection ring 642 may be brazed to the outside surface 636 of the PDC 610 and the top edge 644 or the top surface 641 of the tool body 602. In some embodiments, the surface protection ring 642 may be glued to the outside surface 636 of the PDC 610 and the top edge 644 or the top surface 641 of the tool body 602. In some embodiments, the surface protection ring 642 may be formed during a sintering or welding process that bonds the first and second surface structures 632, 634 to each other, such as forming the protection ring while applying temperature and pressure in the sintering or welding process. The surface protection ring 642 may extend around the complete circumference of the PDC 610 (e.g., may extend 360° around the circumference of the PDC 610). In some embodiments, the surface protection ring 642 runs at least around a portion of the circumference of the PDC 610, (e.g., at least 355°, or at least 300°).

[0056] FIG. 7 shows a simplified, cross-sectional view of a PDC 710 within a pocket 714 of a tool body 702, according to embodiments of the present disclosure. The PDC 710 may be similar to either the PDC cutting elements 110 described above with reference to FIG. 1 or the PDC bearing elements 210a, 210b, 210c described above with reference to FIGS. 2A-2C. The tool body 702 may be similar to the bit body 102 or the carrier bodies 202a, 202b, 202c described above. In some embodiments, to reduce the need for relatively tight tolerances and precise fits when joining elements together via the surface structures, one or more connecting elements 746 may be provided between the pocket 714 and the PDC 710. The connecting element 746 may be provided with first element surface structures 749 and second element surface structures 748 on respective opposing sides of the connecting element 746. The connecting element 746 may be a film, a sheet, or a tape, or any other shape with two opposing surfaces. The connecting element 746 may be formed from plastics, ceramics, silicon, aluminum oxide, glass, steel, non-ferrous metal, or composite materials. The connecting element 746 may be electrically conductive or non- conductive. The connecting element 746 may possess high heat conductivity or low heat conductivity. The connecting element 746 includes a first element side 743 facing the inside surface 730 of the pocket 714, and a second element side 745 facing the outside surface 736 of the substrate 722. The first element side 743 is concentric with the second element side 745 in a lateral portion of the connecting element 746, and the first element side 743 is parallel with the second element side 745 in a bottom portion of the connecting element 746.

[0057] In FIG. 7, the pocket 714 is shown with the first plating 729 and the PDC 710 is shown with the second plating 727. A bonded interface between the PDC 710 and the connecting element 746 may be formed via the second plating surface structures 738 and the second element surface structures 748 formed on the second element side 745. A bonded interface between the connecting element 746 and the pocket 714 may also be formed via the first plating surface structures 740 and the first element surface structures 749 formed on the first element side 743. In this manner, the PDC 710 may be bonded into the pocket 714. One or more of the connecting elements 746 may also be used without the second plating 727 and / or the first plating 729.

[0058] The connecting element 746 may be similar to a connecting element as described in U.S. Patent Application Publication No. 2024 / 0306311 Al. published September 12, 2024, and titled “Connection of Two Components With One Connecting Element,’’ the disclosure of which is hereby incorporated herein in its entirety by this reference. The single connecting element may comprise KLETTWELDING tape available from NanoWired GmbH of Gemsheim, Germany.

[0059] The bonding methods described herein are not limited to the shapes of the PDC elements and the pockets shown in FIGS. 3A-7. FIG. 8 shows a simplified, cross-sectional view of a PDC 810 within a pocket 814 of a tool body 802, according to embodiments of the present disclosure. The PDC 810 may be similar to either the PDC cutting elements 110 described above with reference to FIG. 1 or the PDC bearing elements 210a, 210b, 210c described above with reference to FIGS. 2A-2C. The tool body 802 may be similar to the bit body 102 or the carrier bodies 202a, 202b, 202c described above. As shown in FIG. 8, a PDC 810 may comprise a poly crystalline diamond table 812 and a tungsten carbide substrate 822 similar to the PDCs described above. The lateral outside surface 835 of the outside surface 836 of the PDC 810 may comprise an angled surface such that a cross- sectional profile of the tungsten carbide substrate 822 of the PDC 810 is not rectangular. For example, the lateral outside surface 835 of the outside surface 836 may be formed at an angle 850 relative to a bottom outside surface 837 of the tungsten carbide substrate 822 that is greater than 90 degrees such that the tungsten carbide substrate 822 has a frustoconical shape and a trapezoidal cross-sectional profile.

[0060] The pocket 814 may be formed to have a profile substantially matching that of the PDC 810. For example, a lateral inside surface 831 of the pocket 814 may be formed at an angle 852 relative to a bottom inside surface 833 of the pocket 814. The angle 852 may be greater than 90 degrees. In some embodiments, the angle 852 may be about the same as the angle 850. In some embodiments, the angle 852 may be greater than the angle 850. With lateral outside surface 835 of the tungsten carbide substrate 822 formed at the angle 850 relative to the bottom outside surface 837. and with the lateral inside surface 831 of the pocket 814 formed at the angle 852 relative to the bottom inside surface 833, damage to the first surface structures 832 of the pocket 814 and second surface structures 834 of the PDC 810 may be prevented during insertion of the PDC 810 into the pocket 814. This helps to ensure that the first surface structures 832 and the second surface structures 834 form a strong bonding interface upon application of pressure and optionally temperature to create the bond between the PDC 810 and the pocket 814.

[0061] In some embodiments, angles 850, 852 may be from about 91 degrees and 150 degrees. In some embodiments, angles 850, 852 may be from about 91 degrees and 120 degrees. In some embodiments, the angles 850, 852 may be from about 91 degrees and 100 degrees. With the angle 850 between the lateral outside surface 835 and the bottom outside surface 837, and with the angle 852 between the lateral inside surface 831 and bottom inside surface 833, joining the PDC 810 and the pocket 814 is facilitated.

[0062] Not all of the lateral outside surface 835 of the tungsten carbide substrate 822 is required to have an angle larger than 90 degrees relative to the bottom outside surface 837. There can be a perpendicular portion 854 of the lateral outside surface 835 of the tungsten carbide substrate 822 that has an angle relative to the bottom outside surface 837 of 90 degrees and an angled portion 855 oriented at the angle 850 greater than 90 degrees. The perpendicular portion 854 may vertically extend along a portion of the tungsten carbide substrate 822 between the poly crystalline diamond table 812 and the angled portion 855. The angled portion 855 vertically extends below the perpendicular portion 854 and up to a bottom end 820 of the PDC 810. In some embodiments, instead of a frustoconical shape, which leads to a circular cross-section of the tungsten carbide substrate 822 perpendicular to a longitudinal axis 856 of the PDC 810, a portion of the tungsten carbide substrate 822 may have an angled cross-section in a plane perpendicular to the longitudinal axis 856 such that the tungsten carbide substrate 822 is in the form of a truncated pyramid.

[0063] In some embodiments, there is a lateral gap 858 with a lateral gap size between the lateral outside surface 835 and the lateral inside surface 831 and there is a bottom gap 860 with a bottom gap size between the bottom outside surface 837 and the bottom inside surface 833. The gap size of the lateral gap 858 and the bottom gap 860 may be the same or different. In some embodiments, the gap size of the lateral gap 858 is larger than the bottom gap 860. In some embodiments, the gap size of the lateral gap 858 size is smaller than the bottom gap 860. Depending on the needs of the surface structures and / or the braze filler material in the lateral and bottom gaps 858, 860 and the optional plating on both or only one of the inside surface of the pocket and the outside surface of the substrate, (see FIGS. 3A-7) the gap size of the lateral gap 858 and the gap size of the bottom gap 860 may be in the range of 5 microns to 300 microns. While the lateral gap 858 and bottom gap 860 are described with reference to FIG. 8, similar gaps may be provided in the embodiments shown in FIGS. 3A-7.

[0064] Other shapes of profiles may be used for the PDC 810 and the pocket 814 in addition to those shown in FIG. 8. For example, instead of the angle 850 between the lateral outside surface 835 and the bottom outside surface 837 of the PDC 810, the PDC 810 may have a rounded cross-sectional profile, such as a semi-ovular or semi- spherical shaped profile. The pocket 814 may be formed with a corresponding cross- sectional profile to the PDC 810. The bonding interface between the PDC 810 and the pocket 814 may further utilize plating attached to one or both of the outside surface 836 of the PDC 810 and / or the inside surface 830 of the pocket 814 as described above. The bonding interface may also utilize a connecting element as described above with reference to FIG. 7.

[0065] In some embodiments, various features described above may be combined in any suitable combination. For example, surface structures may be provided on one or both of a PDC and pocket. Additionally, a braze filler metal may be applied to the surface structures. The braze filler metal may fill a volume between the surface structures and further strengthens the bonding between the PDC and the body. In a joint formed by a combination of surface structures and a braze filler metal, a smaller density of surface structures (e.g. micro- or nanowires) per surface may be used to leave more space between surface structures for the braze filler metal. A braze filler metal melting at low temperatures, such as a copper brazing, may run into the spaces between the surface structures when applied in molten condition.

[0066] As described hereinabove, existing weak braze joints may be strengthened by providing a plating on one or both of the joining surfaces, such as on an outside surface of the PDC and / or an inside surface of the pocket prior to brazing the PDC into the pocket. Furthermore, a joint between the elements may utilize surface structures directly on the surfaces to be joined or on the plating provided on one or both of the surfaces to be joined. In some embodiments, a tungsten carbide substrate that is bonded to a PDC is plated with nickel and then surface structures are formed on the nickel plating. In some embodiments, the surface structures are directly formed on the surface of the tungsten carbide substrate, since this process can also be applied to ceramics and cermet composites. The bond strength formed between the PDC and the body may be sufficient to withstand shear forces applied to the PDC during downhole operations even at elevated temperatures. The surface structures may be formed from an electrically conductive material. The surface structures may support heat transport from the PDC to the tool body.

[0067] Using a low temperature process joining bodies comprising surface structure with and without metal plating enables a strong metal -to-metal joint to be formed.

[0068] Although embodiments of methods of bonding PDCs to bodies of industrial tools are described above with reference to earth-boring tools, embodiments of the present disclosure may be used to join any ty pe of PDC to any type of metal body of any industrial tool, such as PDC bearings to metal bodies in rotor and stator bearing units (male, female, thrust, etc.), alternator bearings, etc.

[0069] The embodiments of the disclosure described above and illustrated in the accompanying drawings do not limit the scope of the disclosure, which is encompassed by the scope of the appended claims and their legal equivalents. Any equivalent embodiments are within the scope of this disclosure. Indeed, various modifications of the disclosure, in addition to those shown and described herein, such as alternate useful combinations of the elements described, will become apparent to those skilled in the art from the description. Such modifications and embodiments also fall within the scope of the appended claims and equivalents.

Claims

CLAIMSWhat is claimed is:

1. An industrial tool comprising: a tool body comprising a pocket, the pocket having an inside surface: a poly crystalline diamond compact (“PDC”) comprising a poly crystalline diamond table and a substrate, the PDC disposed at least partially within the pocket; and surface structures protruding from at least one or both of an outside surface of the PDC or the inside surface of the pocket, wherein the PDC is secured to the tool body via the surface structures.

2. The industrial tool of claim 1, wherein the surface structures comprise wires.

3. The industrial tool of claim 1, wherein the surface structures comprise first surface structures protruding from the inside surface of the pocket and second surface structures protruding from the outside surface of the PDC, and wherein the PDC is secured to the tool body via the first surface structures and the second surface structures.

4. The industrial tool of claim 3, wherein the first surface structures are sintered with or welded to the second surface structures.

5. The industrial tool of claim 3, further comprising a connecting element between the first surface structures and the second surface structures, the connecting element comprising third surface structures and fourth surface structures, wherein the PDC is secured to the tool body via the first surface structures, the second surface structures, the third surface structures, and the fourth surface structures.

6. The industrial tool of claim 1 , further comprising a plating on one or both of the inside surface of the pocket or the outside surface of the PDC, the surface structures protruding from the plating.

7. The industrial tool of claim 1, wherein the PDC and the tool body form part of an axial bearing or a radial bearing in a downhole tool.

8. The industrial tool of claim 1, wherein the inside surface of the pocket is separated from the outside surface of the PDC by a gap, wherein the surface structures are in the gap, and wherein a protection ring seals the gap from fluid ingress.

9. The industrial tool of claim 1 , further comprising a brazing material disposed between the surface structures.

10. The industrial tool of claim 1, wherein at least a portion of the substrate has a trapezoidal cross-sectional profile.

11. A method of bonding a PDC to a tool body, the method comprising: forming a pocket in the tool body, the pocket having an inside surface; forming protruding surface structures on at least one or both of an outside surface of thePDC or the inside surface of the pocket; inserting the PDC at least partially within the pocket; and bonding the PDC to the tool body via the protruding surface structures.

12. The method of claim 11, further comprising plating one or both of the outside surface of the PDC or the inside surface of the pocket and then forming the protruding surface structures on the plating.

13. The method of claim 11, further comprising applying vibrations to the PDC and the tool body during bonding.

14. The method of claim 11, wherein forming the protruding surface structures comprises forming first protruding surface structures on the inside surface of the pocket and forming second protruding surface structures on the outside surface of the PDC, and wherein bonding the PDC to the tool body comprises bonding the PDC to the tool body via the first protruding surface structures and the second protruding surface structures.

15. The method of claim 14, further comprising sintering or welding the first protruding surface structures to the second protruding surface structures.

16. The method of claim 14, further comprising plating the outside surface of the PDC prior to forming the second protruding surface structures on the outside surface of the PDC.

17. The method of claim 1 1 , wherein the protruding surface structures are in a gap between the inside surface of the pocket and the outside surface of the PDC, and wherein the method further comprises sealing the protruding surface structures from fluid ingress by forming a protection ring to seal the gap.

18. A method of bonding a PDC to a tool body, the method comprising: forming a pocket in the tool body, the pocket having an inside surface; plating one or both of an outer surface of the PDC or the inside surface of the pocket; and brazing the PDC to the tool body with a braze filler metal.

19. The method of claim 18, wherein plating comprises plating the one or both of the outer surface of the PDC or the inside surface of the pocket via an electroplating process.

20. The method of claim 18, wherein plating comprises plating the one or both of the outer surface of the PDC or the inside surface of the pocket with a metal or a metal alloy comprising at least one element selected from among cobalt, nickel, iron, titanium and copper.

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