Abstract: A polycrystalline element includes a table formed of polycrystalline diamond. The table includes a first surface; a second surface spaced apart from the first surface; and at least one side extending between the first surface and the second surface. The table also includes a plurality of extensions also formed of polycrystalline diamond, wherein at least one extension of the plurality of extensions extends away from at least one of the first surface and the at least one side. A radial line extends radially outward from a center axis of the first surface intersects each of a long axis of a subset of a plurality of extensions. Optionally, the polycrystalline diamond of at least one extension of the plurality of extensions is contiguous with the polycrystalline diamond of the table. The polycrystalline element may be used in downhole tools for boring and well drilling, machine tools, and bearings.

Abstract: The disclosure discloses a polycrystalline diamond composite sheet having a continuous gradient transition layer and a 3D printing preparation method thereof. The polycrystalline diamond composite sheet consists of a polycrystalline diamond layer, a continuous gradient transition layer, and a cemented carbide substrate from top to bottom, in which the continuous gradient transition layer consists of diamond and cemented carbide. Along a direction from the cemented carbide substrate to the polycrystalline diamond layer, a content of the cemented carbide in the continuous gradient transition layer decreases from 100% to 0, and a content of the diamond increases from 0 to 100%. By designing and combining the continuous gradient transition layer with 3D printing technology, the disclosure realizes a continuous change in the two materials of diamond and cemented carbide, thereby eliminating the sudden change interface of the materials inside the diamond composite sheet.

Abstract: The disclosure discloses a polycrystalline cubic boron nitride composite sheet having a continuous gradient structure and a preparation method thereof. The polycrystalline cubic boron nitride composite sheet consists of a cemented carbide substrate, a continuous gradient layer, and a CBN layer from bottom to top. The continuous gradient layer contains cemented carbide and CBN, a content of CBN increases in continuous gradient from bottom to top, while a content of the cemented carbide decreases in continuous gradient from bottom to top. A volume fraction D of CBN and a volume fraction M of cemented carbide in the continuous gradient layer both satisfy exponential gradient functions. At the same time, the disclosure uses direct ink writing 3D printing technology with slurry to realize the preparation of the polycrystalline cubic boron nitride composite sheet having the continuous gradient structure.

Abstract: A polycrystalline element includes a table formed of polycrystalline diamond. The table includes a first surface; a second surface spaced apart from the first surface; and at least one side extending between the first surface and the second surface. The table also includes a plurality of extensions also formed of polycrystalline diamond, wherein at least one extension of the plurality of extensions extends away from at least one of the first surface and the at least one side. A radial line extends radially outward from a center axis of the first surface intersects each of a long axis of a subset of a plurality of extensions. Optionally, the polycrystalline diamond of at least one extension of the plurality of extensions is contiguous with the polycrystalline diamond of the table. The polycrystalline element may be used in downhole tools for boring and well drilling, machine tools, and bearings.

Abstract: A polycrystalline element includes a table formed of polycrystalline diamond. The table includes a first surface; a second surface spaced apart from the first surface; and at least one side extending between the first surface and the second surface. The table also includes a plurality of extensions also formed of polycrystalline diamond, wherein at least one extension of the plurality of extensions extends away from at least one of the first surface and the at least one side. The at least one extension of the plurality of extensions includes a first portion that is polyhedral shaped. Optionally, the polycrystalline diamond of at least one extension of the plurality of extensions is contiguous with the polycrystalline diamond of the table. The polycrystalline element may be used in downhole tools for boring and well drilling, machine tools, and bearings.

Abstract: A polycrystalline element includes a table formed of polycrystalline diamond. The table includes a first surface; a second surface spaced apart from the first surface; and at least one side extending between the first surface and the second surface. The table also includes a plurality of extensions also formed of polycrystalline diamond, wherein at least one extension of the plurality of extensions extends away from at least one of the first surface and the at least one side. A radial line extends radially outward from a center axis of the first surface intersects each of a long axis of a subset of a plurality of extensions. Optionally, the polycrystalline diamond of at least one extension of the plurality of extensions is contiguous with the polycrystalline diamond of the table. The polycrystalline element may be used in downhole tools for boring and well drilling, machine tools, and bearings.

Abstract: The disclosure relates to a polycrystalline diamond composite sheet having a ripple-shaped gradient layer and a preparation method thereof. The polycrystalline diamond composite sheet consists of a cemented carbide substrate, a ripple-shaped gradient layer of a multi-layer structure, and a polycrystalline diamond layer from bottom to top. In the ripple-shaped gradient layer, a content of polycrystalline diamond increases from bottom to top, and a content of cemented carbide decreases from bottom to top. In the ripple-shaped gradient layer, an amplitude of a ripple-shaped structure is 0.2 to 0.6 mm, a wavelength is 1 to 2 mm, a spacing between an upper ripple and a lower ripple of a top layer is set to a gradient of (t/2 to t) mm to t mm from a peak to a trough, and spacings between an upper ripple and a lower ripple of remaining layers are all t mm, wherein t is 0.05 to 0.4.

Abstract: The disclosure provides a gradient structure cubic boron nitride composite sheet and a preparation method thereof. The gradient structure cubic boron nitride composite sheet consists of a cemented carbide substrate, a gradient transition layer, and a CBN layer from bottom to top. The gradient transition layer consists of N gradient layers, and the N is 4 to 18. From bottom to top, there are sequentially a first gradient layer, a second gradient layer, an Nth gradient layer, and so on. Any of the gradient layers consists of CBN and cemented carbide, in which the volume fraction of the cemented carbide in the Nth layer is 5 to 30% less than the volume fraction of the cemented carbide in the N?1th layer, and the volume fraction of the CBN in the Nth layer is 5 to 30% more than the volume fraction of the CBN in the N?1th layer.

Abstract: A polycrystalline diamond compact including a polycrystalline diamond layer and a cemented carbide substrate. The polycrystalline diamond layer is in the form of a cylinder including an upper surface, a bottom surface, and a side wall connecting the upper surface and the bottom surface. The cemented carbide substrate is bonded to the bottom surface of the polycrystalline diamond layer. The upper surface includes a center part and an edge part. The edge part includes a plurality of radially distributed cutting edges and cutting removal grooves. The plurality of cutting edges and cutting removal grooves are alternately distributed on the upper surface. One end of each of the plurality of cutting edges and cutting removal grooves extends to communicate with the center part, and the other end of each of the plurality of cutting edges and cutting removal grooves extends to communicate with the side wall.

Abstract: A polycrystalline element includes a table formed of polycrystalline diamond. The table includes a first surface; a second surface spaced apart from the first surface; and at least one side extending between the first surface and the second surface. The table also includes a plurality of extensions also formed of polycrystalline diamond, wherein at least one extension of the plurality of extensions extends away from at least one of the first surface and the at least one side. A radial line extends radially outward from a center axis of the first surface intersects each of a long axis of a subset of a plurality of extensions. Optionally, the polycrystalline diamond of at least one extension of the plurality of extensions is contiguous with the polycrystalline diamond of the table. The polycrystalline element may be used in downhole tools for boring and well drilling, machine tools, and bearings.

Abstract: A polycrystalline element includes a table formed of polycrystalline diamond. The table includes a first surface; a second surface spaced apart from the first surface; and at least one side extending between the first surface and the second surface. The table also includes a plurality of extensions also formed of polycrystalline diamond, wherein at least one extension of the plurality of extensions extends away from at least one of the first surface and the at least one side. The at least one extension of the plurality of extensions includes a first portion that is polyhedral shaped. Optionally, the polycrystalline diamond of at least one extension of the plurality of extensions is contiguous with the polycrystalline diamond of the table. The polycrystalline element may be used in downhole tools for boring and well drilling, machine tools, and bearings.

Abstract: A polycrystalline element includes a table formed of polycrystalline diamond. The table includes a first surface; a second surface spaced apart from the first surface; and at least one side extending between the first surface and the second surface. The table also includes a plurality of extensions also formed of polycrystalline diamond, wherein at least one extension of the plurality of extensions extends away from at least one of the first surface and the at least one side. Optionally, the polycrystalline diamond of at least one extension of the plurality of extensions is contiguous with the polycrystalline diamond of the table. The polycrystalline element may be used in downhole tools for boring and well drilling, machine tools, and bearings.

Abstract: A polycrystalline diamond compact including a cemented carbide substrate and a polycrystalline diamond layer bonded to the cemented carbide substrate. The polycrystalline diamond layer is nonplanar and includes a central part and a peripheral part surrounding the central part. The central part includes a protruding surface relative to the peripheral part. The protruding surface is spherical or planar. The peripheral part includes a plurality of radially-disposed ridges.

Abstract: A polycrystalline diamond compact including a polycrystalline diamond layer and a cemented carbide substrate. The polycrystalline diamond layer is in the form of a cylinder including an upper surface, a bottom surface, and a side wall connecting the upper surface and the bottom surface. The cemented carbide substrate is bonded to the bottom surface of the polycrystalline diamond layer. The upper surface includes a center part and an edge part. The edge part includes a plurality of radially distributed cutting edges and cutting removal grooves. The plurality of cutting edges and cutting removal grooves are alternately distributed on the upper surface. One end of each of the plurality of cutting edges and cutting removal grooves extends to communicate with the center part, and the other end of each of the plurality of cutting edges and cutting removal grooves extends to communicate with the side wall.

Abstract: A polycrystalline element includes a table formed of polycrystalline diamond. The table includes a first surface; a second surface spaced apart from the first surface; and at least one side extending between the first surface and the second surface. The table also includes a plurality of extensions also formed of polycrystalline diamond, wherein at least one extension of the plurality of extensions extends away from at least one of the first surface and the at least one side. Optionally, the polycrystalline diamond of at least one extension of the plurality of extensions is contiguous with the polycrystalline diamond of the table. The polycrystalline element may be used in downhole tools for boring and well drilling, machine tools, and bearings.

Abstract: A polycrystalline diamond compact including a cemented carbide substrate and a polycrystalline diamond layer bonded to the cemented carbide substrate. The cemented carbide substrate is cylindrical and includes a circumferential wall. The polycrystalline diamond layer includes a central part including between 8 and 15 wt. % of cobalt and an outer part including between 0.5 and 2 wt. % of cobalt. The outer part is a columnar ring belt and includes a chamfer. The outer part includes an upper surface, a side surface connected to the circumferential wall of the cemented carbide substrate, and a chamfer surface connecting the upper surface and the side surface. The chamfer includes a first terminal connected to the upper surface of the outer part and a second terminal connected to the side surface of the outer part.

Abstract: A method for making a polycrystalline diamond compact. The method includes: 1) preparing a workblank of a polycrystalline diamond compact; and 2) thermally- or cold-etching the curved surface of the workblank of the polycrystalline diamond compact using laser. The thermally- or cold-etching the curved surface of the workblank of the polycrystalline diamond compact includes: employing a laser generator to produce a laser beam, expanding the laser beam, focusing the laser beam, to yield an energy concentration area on the surface of the workblank of the polycrystalline diamond compact, and etching the curved surface using the energy concentration area.

Abstract: A polycrystalline diamond compact including a cemented carbide substrate and a polycrystalline diamond layer disposed on the cemented carbide substrate. The polycrystalline diamond layer is nonplanar and includes a first curved surface, a second curved surface, and a side surface directly connected to the cemented carbide substrate. The first curved surface is connected to the second curved surface. The joint of the first curved surface and the second curved surface protrudes to form a first cutting edge. The joints of the first curved surface and the second curved surface and the side surface protrudes to form a plurality of second cutting edges.

Abstract: A polycrystalline diamond compact including a cemented carbide substrate and a polycrystalline diamond layer bonded to the cemented carbide substrate. The polycrystalline diamond layer is nonplanar and includes a central part and a peripheral part surrounding the central part. The central part includes a protruding surface relative to the peripheral part. The protruding surface is spherical or planar. The peripheral part includes a plurality of radially-disposed ridges.

Abstract: A polycrystalline diamond compact including a cemented carbide substrate and a polycrystalline diamond layer bonded to the cemented carbide substrate. The cemented carbide substrate is cylindrical and includes a circumferential wall. The polycrystalline diamond layer includes a central part including between 8 and 15 wt. % of cobalt and an outer part including between 0.5 and 2 wt. % of cobalt. The outer part is a columnar ring belt and includes a chamfer. The outer part includes an upper surface, a side surface connected to the circumferential wall of the cemented carbide substrate, and a chamfer surface connecting the upper surface and the side surface. The chamfer includes a first terminal connected to the upper surface of the outer part and a second terminal connected to the side surface of the outer part.