An earth-boring tool having at least one cutting element with a multi-friction cutting face provides for the steering of formation cuttings as the cuttings slide across the cutting face. The multi-friction cutting element includes a diamond table bonded to a substrate of superabrasive material. The diamond table has a cutting face formed thereon with a cutting edge extending along a periphery of the cutting face. The cutting face has a first area having an average surface finish roughness less than an average surface finish roughness of a second area of the cutting face, the two areas separated by a boundary having a proximal end proximate a tool crown and a distal end remote from the tool crown.

Embodiments disclosed herein are directed to a superabrasive compact including one or more superabrasive cutting portions or segments, rotary drill bits including one or more superabrasive compacts, and related methods (e.g., methods of fabricating and/or operating the superabrasive compacts). For example, the superabrasive compact may include polycrystalline diamond that may form at least a portion of a working surface of the superabrasive compact.

A downhole cutting apparatus includes a cutter block. The cutter block includes a formation facing surface with cutting elements coupled thereto. The cutting elements are arranged such that at least one cutting element has a different exposure relative to the formation facing surface than at least one other cutting element. In some embodiments, a row of cutting elements may have a gradually changing exposure. The exposure may change such that cutting elements nearer the gauge of the cutter block have less exposure than cutting elements farther from the gauge of the cutter block. In additional embodiments, an underreamer may include multiple cutter blocks. The cutter blocks may each have a different configuration in a backreaming portion, gauge portion, underreaming portion, any part thereof, or in a combination of the foregoing.

A drill bit for cutting formation comprises a bit body, a plurality of cutters, and a plurality of blades with pockets to accommodate the cutters, respectively. Each of the plurality of cutters has a substrate, an ultra-hard layer, an inclined surface on the top of the ultra-hard layer, wherein the inclined surface slants downward from a cutting edge to a trailing edge. The cutter can improve cutting efficiency and service life.

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.

Embodiments of the invention relate to polycrystalline diamond compacts (“PDCs”) including a polycrystalline diamond (“PCD”) table having a structure for enhancing at least one of abrasion resistance, thermal stability, or impact resistance. In an embodiment, a PDC includes a PCD table. The PCD table includes a lower region including a plurality of diamond grains exhibiting a lower average grain size and at least an upper region adjacent to the lower region and including a plurality of diamond grains exhibiting an upper average grain size. The lower average grain size may be at least two times greater than that of the upper average grain size. The PDC includes a substrate having an interfacial surface that is bonded to the lower region of the PCD table. Other embodiments are directed methods of forming PDCs, and various applications for such PDCs in rotary drill bits, bearing apparatuses, and wire-drawing dies.

A cutting element includes a body, a non-planar cutting face formed on a first end of the body, and an edge formed around a perimeter of the cutting face. The cutting face includes a central raised portion, and the edge has an edge angle defined between the cutting face and a side surface of the body. The edge angle varies around the perimeter of the cutting face and includes an acute edge angle defined by a portion of the cutting face extending downwardly from the edge to a depth from the cutting angle. The portion of the edge defining the acute edge angle may be directly adjacent: a side surface of the cutting element; a bevel of the cutting element; or a flat region at the perimeter of the cutting element or bevel.

Cutting elements for earth-boring tools may include a cutting edge located proximate to a periphery of the cutting element. The cutting edge may be positioned and configured to contact an earth formation during an earth-boring operation. The cutting edge may include a first portion having a first radius of curvature and a second portion having a second, larger radius of curvature. The second portion may be circumferentially offset from the first portion.

The disclosure relates to a polycrystalline diamond compact including a cemented carbide substrate and a diamond layer, with the diamond layer disposed at the top face of cemented carbide substrate, there are at least two continuous varying cambered convex ridges at the end face of the diamond layer, each cambered convex ridge extending from the edge of the end face to the center of end face, with the width of each continuous varying cambered convex ridge increasing gradually from the edge of the end face to the center of the end face. Both ploughing effect and the fracture drilling property of the PDC cutting face with each continuous varying cambered convex ridge are improved, the cutting resistance during drilling is reduced and thus the rate of penetration of the PDC bit is increased. A drilling bit with the polycrystalline diamond compact disposed at the end thereof is provided in the disclosure.

A cutting element for downhole drilling and related earth-boring tool for downhole drilling. The cutting element may include a substrate and a polycrystalline diamond material affixed to the substrate at an interface. The polycrystalline diamond material may include a raised cutting surface having at least two cutting edges, and first transition surfaces between the at least two cutting edges of the raised cutting surface and a side surface of the cutting element. The first transition surfaces may include multiple planar surfaces.