Polycrystalline ultra-hard constructions comprise a polycrystalline ultra-hard material body and two or more support members attached to the body by braze material. The support members include a backside support member and a side support member. The side support member is a one- or two-piece construction, and is positioned circumferentially around and extends axially along the body or both the body and the backside support member such that a working surface of the body remains exposed. The support members can be configured to provide a mechanical attachment or interlocking attachment with the body or another support member. The braze materials used in the construction can be different and selected to enhance the attachment and/or reduce the creation of thermal stress within the construction during assembly. The support members can be selected having different thermal expansion characteristics that also operate to reduce the thermal stress during construction assembly.

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.

A cutting element for a drill bit includes a body having a face at an end thereof. The face includes a ramp, a first side region, a second side region, and a ridge thereon. The ramp has a curved edge along a periphery of the face, a first side, and a second side. The first side and the second side extend from opposite ends of the curved edge and converge at a location along the face. The ridge extends along the face from a chamfer along a peripheral edge of the face to the location. The ridge is positioned between the first side region and the second side region. The first side region extends between the periphery, the ridge, and the first side. The second side region extends between the periphery, the ridge, and the second side. The ramp extends from the first side region to the second side region.

A cutting tool is a cutting tool comprising a substrate and a coating film disposed on the substrate, in which the coating film includes a first layer, the first layer is composed of an alternate layer where a first unit layer and a second unit layer are alternately stacked, the first unit layer is composed of Ti.sub.1-a-bAl.sub.aCe.sub.bN, a is between greater than or equal to 0.350 and equal to or less than 0.650, b is between greater than or equal to 0.001 and equal to or less than 0.100, the second unit layer is composed of Ti.sub.cSi.sub.1-cN, and c is between greater than or equal to 0.20 and equal to or less than 0.99.

A polycrystalline diamond compact (PDC), which is attached or bonded to a substrate to form a cutter for a drill bit, is comprised of sintered polycrystalline diamond interspersed with a seed material which has a hexagonal close packed (HCP) crystalline structure. A region of the sintered polycrystalline diamond structure, near one or more of its working surfaces, which has been seeded with an HCP seed material prior to sintering, is leached to remove catalyst. Selectively seeding portions or regions of a sintered polycrystalline diamond structure permits differing leach rates to form leached regions with differing distances or depths and geometries.

Systems and methods are disclosed for a rotating superhard cutting element. The rotating cutting element includes a substrate comprising a rotating portion and a stable portion. The stable portion has a cavity and is configured to be fixed to a blade of a drill bit. The rotating cutting element further includes a retainer that rotatably secures the rotating portion of the substrate in the cavity of the stable portion of the substrate, and a cutting layer on the rotating portion of the substrate. The cutting layer has a plurality of cutting surfaces. One of the plurality of cutting surfaces has a property different from another one of the plurality of cutting surfaces. The cutting layer is configured to rotate with respect to the stable portion of the substrate and use one of the plurality of cutting surfaces based on a characteristic of a formation to be cut.

A cutting element for a drill bit is advanceable into a subterranean formation to form a wellbore. The cutting element includes an element body having a face at an end thereof, and a ridge. The element body has a face at an end thereof. The face has a ramp and a pair of side regions thereon. The ramp has a curved edge along a periphery of the face and two sides. Each of the two sides extends from opposite ends of the curved edge and converges at a location along the face. The face has a chamfer along a peripheral edge thereof. The ridge is between the chamfer and the location. Each of the pair of side regions is positioned on opposite sides of the ridge and extends between the periphery, the ridge, and one of the two sides of the ramp whereby the chamfer engages a wall of the wellbore and extrudate is drawn along the pair of side regions.

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.

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.

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.