Methods of laser cutting polycrystalline diamond tables and polycrystalline diamond compacts are disclosed. Laser cutting of the polycrystalline diamond table provides an alternative to electrical-discharge machining (“EDM”), grinding with a diamond wheel, or lapping with a diamond wheel. Grinding or lapping with a diamond wheel is relatively slow and expensive, as diamond is used to remove a diamond material. EDM cutting of the polycrystalline diamond table is sometimes impractical or even impossible, particularly when the cobalt or other infiltrant or catalyst concentration within the polycrystalline diamond table is very low (e.g., in the case of a leached polycrystalline diamond table). As such, laser cutting provides a valuable alternative machining method that may be employed in various processes such as laser scribing, laser ablation, and laser lapping.

A cutting bit includes a body, a plurality of blades, and at least one ultrahard insert cast directly into at least one of the plurality of blades. The ultrahard insert is positioned with a rear face directly contacting the blade.

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.

Polycrystalline diamond may include a working surface and a peripheral surface extending around an outer periphery of the working surface. The polycrystalline diamond includes a first volume including an interstitial material and a second volume having a leached region that includes boron and titanium. A method of fabricating a polycrystalline diamond element may include positioning a first volume of diamond particles adjacent to a substrate, the first volume of diamond particles including a material that includes a group 13 element, and positioning a second volume of diamond particles adjacent to the first volume of diamond particles such that the first volume of diamond particles is disposed between the second volume of diamond particles and the substrate, the second volume of diamond particles having a lower concentration of material including the group 13 element than the first volume of diamond particles.

A cutter element includes a base portion having a central axis, a first end, and a second end. In addition, the cutter element includes a cutting layer fixably mounted to the first end of the base portion. The cutting layer includes a cutting face distal. The cutting face includes a planar central region centered relative to the central axis and disposed in a plane oriented perpendicular to the central axis. The cutting face also includes a plurality of circumferentially-spaced cutting regions disposed about the planar central region. Each cutting region extends from the planar central region to the radially outer surface of the cutting layer. Each cutting region slopes axially toward the base portion moving radially outward from the planar central region to the radially outer surface of the cutting layer. Further, the cutting face includes a plurality of circumferentially-spaced relief regions disposed about the planar central region. Each relief region extends from the planar central region to the radially outer surface. Each relief region slopes axially toward the base portion moving radially outward from the planar central region to the radially outer surface of the cutting layer. The plurality of cutting regions and the plurality of relief regions are circumferentially arranged in an alternating manner such that one relief region is circumferentially disposed two circumferentially adjacent cutting regions of the plurality of cutting regions.

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.

Methods of laser cutting polycrystalline diamond tables and polycrystalline diamond compacts are disclosed. Laser cutting of the polycrystalline diamond table provides an alternative to electrical-discharge machining (EDM), grinding with a diamond wheel, or lapping with a diamond wheel. Grinding or lapping with a diamond wheel is relatively slow and expensive, as diamond is used to remove a diamond material. EDM cutting of the polycrystalline diamond table is sometimes impractical or even impossible, particularly when the cobalt or other infiltrant or catalyst concentration within the polycrystalline diamond table is very low (e.g., in the case of a leached polycrystalline diamond table). As such, laser cutting provides a valuable alternative machining method that may be employed in various processes such as laser scribing, laser ablation, and laser lapping.

Cutting elements for earth-boring tools may include a polycrystalline, superabrasive material secured to an end of a substrate. The polycrystalline, superabrasive material may include a first transition surface and a second transition surface. A waveform may extend around a circumference of the second transition surface, a surface of the waveform tapered toward from the substrate and extending radially from the second transition surface toward the central axis. The surface of the waveform may extend from the second transition surface to a planar surface of the polycrystalline located at a same distance from the substrate as troughs of the waveform surface, the planar surface oriented perpendicular, and located proximate, to the central axis.

Polycrystalline diamond includes a working surface and a peripheral surface extending around an outer periphery of the working surface. The polycrystalline diamond includes a first volume including an interstitial material and a second volume having a leached region that includes boron and titanium. A method of fabricating a polycrystalline diamond element includes positioning a first volume of diamond particles adjacent to a substrate, the first volume of diamond particles including a material that includes a group 13 element, and positioning a second volume of diamond particles adjacent to the first volume of diamond particles such that the first volume of diamond particles is disposed between the second volume of diamond particles and the substrate, the second volume of diamond particles having a lower concentration of material including the group 13 element than the first volume of diamond particles. Various other articles, assemblies, and methods are also disclosed.

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.