Abstract: Methods of forming polycrystalline diamond compacts include employing field assisted sintering techniques with high temperature and high pressure sintering techniques. For example, a particle mixture that includes diamond particles may be sintered by subjecting the particle mixture to a high temperature and high pressure sintering cycle, and pulsing direct electrical current through the particle mixture during at least a portion of the high temperature and high pressure sintering cycle. The polycrystalline diamond compacts may be used to form cutting elements for earth-boring tools. Sintering systems are configured to perform such sintering processes.

Abstract: An earth-boring drilling tool comprises a cutting element. The cutting element comprises a substrate, a diamond table, and at least one sensing element formed from a doped diamond material disposed at least partially within the diamond table. A method for determining an at-bit measurement for an earth-boring drill bit comprises receiving an electrical signal generated within a doped diamond material disposed within a diamond table of a cutting element of the earth-boring drill bit, and correlating the electrical signal with at least one parameter during a drilling operation.

Abstract: Earth-boring drill bits may include a bit body including blades extending radially over a face of the earth-boring drill bit and cutting elements attached to each blade. Only cutting elements including planar cutting faces may be attached to at least one of the blades. Only cutting elements including nonplanar cutting faces may be attached to at least another of the blades. Only cutting elements including planar cutting faces or only cutting elements including nonplanar cutting faces may be attached to each of the blades. Only cutting elements including nonplanar cutting faces may be attached to a number of the blades that may be unequal to a number of the blades to which only cutting elements comprising planar cutting faces may be attached.

Abstract: Coated diamond particles have solid diamond cores and at least one graphene layer. Methods of forming coated diamond particles include coating diamond particles with a charged species and coating the diamond particles with a graphene layer. A composition includes a substance and a plurality of coated diamond particles dispersed within the substance. An intermediate structure includes a hard polycrystalline material comprising a first plurality of diamond particles and a second plurality of diamond particles. The first plurality of diamond particles and the second plurality of diamond particles are interspersed. A method of forming a polycrystalline compact includes catalyzing the formation of inter-granular bonds between adjacent particles of a plurality of diamond particles having at least one graphene layer.

Abstract: Cutting elements include a volume of superabrasive material. The volume of superabrasive material comprises a front-cutting surface, an end-cutting surface, a cutting edge, and lateral side surfaces extending between and intersecting each of the front-cutting surface and the end-cutting surface. An earth-boring tool may comprise a bit body and at least one cutting element attached to the bit body. Methods of forming cutting elements comprise forming a volume of superabrasive material comprising forming a front-cutting surface, an end-cutting surface, a cutting edge, and lateral side surfaces extending between and intersecting each of the front-cutting surface and the end-cutting surface. Methods of forming earth-boring tools comprise forming a cutting element and attaching the cutting element to an earth-boring tool.

Abstract: Methods for forming cutting elements, methods for forming polycrystalline compacts, and related polycrystalline compacts are disclosed. Grains of a hard material are subjected to a high-pressure, high-temperature process to form a polycrystalline compact. Inclusion of at least one relatively quick spike in system pressure or temperature during an otherwise plateaued temperature or pressure stage accommodates formation of inter-granular bonds between the grains. The brevity of the peak stage may avoid undesirable grain growth. Embodiments of the methods may also include at least one of oscillating at least one system condition (e.g., pressure, temperature) and subjecting the grains to ultrasonic or mechanical vibrations.

Abstract: Methods of forming polycrystalline diamond compacts include employing field assisted sintering techniques with high temperature and high pressure sintering techniques. For example, a particle mixture that includes diamond particles may be sintered by subjecting the particle mixture to a high temperature and high pressure sintering cycle, and pulsing direct electrical current through the particle mixture during at least a portion of the high temperature and high pressure sintering cycle. The polycrystalline diamond compacts may be used to form cutting elements for earth-boring tools. Sintering systems are configured to perform such sintering processes.

Abstract: Coated diamond particles have solid diamond cores and at least one graphene layer. Methods of forming coated diamond particles include coating diamond particles with a charged species and coating the diamond particles with a graphene layer. A composition includes a substance and a plurality of coated diamond particles dispersed within the substance. An intermediate structure includes a hard polycrystalline material comprising a first plurality of diamond particles and a second plurality of diamond particles. The first plurality of diamond particles and the second plurality of diamond particles are interspersed. A method of forming a polycrystalline compact includes catalyzing the fox of inter-granular bonds between adjacent particles of a plurality of diamond particles having at least one graphene layer.

Abstract: Cutting elements for earth-boring applications may include a substrate and a polycrystalline diamond material secured to the substrate. A first region of the polycrystalline diamond material may exhibit a first volume percentage of nanoparticles bonded to diamond grains within the first region. A second region of the polycrystalline diamond material adjacent to the first region may exhibit a second, different volume percentage of nanoparticles bonded to diamond grains within the second region. Methods of making cutting elements for earth-boring applications may involve positioning a first mixture of particles having a first volume percentage of nanoparticles and a second mixture of particles having a second, different volume percentage of nanoparticles within a container.

Abstract: 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.

Abstract: Cutting elements include a volume of superabrasive material. The volume of superabrasive material comprises a front-cutting surface, an end-cutting surface, a cutting edge, and lateral side surfaces extending between and intersecting each of the front-cutting surface and the end-cutting surface. An earth-boring tool may comprise a bit body and at least one cutting element attached to the bit body. Methods of forming cutting elements comprise forming a volume of superabrasive material comprising forming a front-cutting surface, an end-cutting surface, a cutting edge, and lateral side surfaces extending between and intersecting each of the front-cutting surface and the end-cutting surface. Methods of forming earth-boring tools comprise forming a cutting element and attaching the cutting element to an earth-boring tool.

Abstract: Methods for forming cutting elements, methods for forming polycrystalline compacts, and related polycrystalline compacts are disclosed. Grains of a hard material are subjected to a high-pressure, high-temperature process to form a polycrystalline compact. Inclusion of at least one relatively quick spike in system pressure or temperature during an otherwise plateaued temperature or pressure stage accommodates formation of inter-granular bonds between the grains. The brevity of the peak stage may avoid undesirable grain growth. Embodiments of the methods may also include at least one of oscillating at least one system condition (e.g., pressure, temperature) and subjecting the grains to ultrasonic or mechanical vibrations.

Abstract: 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.

Abstract: Cutting elements comprise a multi-portion polycrystalline material. At least one portion of the multi-portion polycrystalline material comprises a higher volume of nanoparticles than at least another portion. Earth-boring tools comprise a body and at least one cutting element attached to the body. The at least one cutting element comprises a hard polycrystalline material. The hard polycrystalline material comprises a first portion comprising a first volume of nanoparticles. A second portion of the hard polycrystalline material comprises a second volume of nanoparticles. The first volume of nanoparticles differs from the second volume of nanoparticles. Methods of forming cutting elements for earth-boring tools comprise forming a volume of superabrasive material, including forming a first portion of the superabrasive material comprising a first volume of nanoparticles.

Abstract: A cutting element for an earth-boring drill bit may include a thermally stable cutting table comprising a polycrystalline diamond material. The polycrystalline diamond material may consist essentially of a matrix of diamond particles bonded to one another and a silicon, silicon carbide, or silicon and silicon carbide material located within interstitial spaces among interbonded diamond particles of the matrix of diamond particles. The cutting table may be at least substantially free of Group VIII metal or alloy catalyst material. The cutting element may further include a substrate and an adhesion material between and bonded to the cutting table and the substrate. The adhesion material may include diamond particles bonded to one another and to the cutting table and the substrate after formation of the preformed cutting table.

Abstract: Cutting elements for earth-boring tools may include a polycrystalline table attached to a portion of a first substrate on which the polycrystalline table was formed. The portion of the first substrate may exhibit a thickness less than a thickness of the first substrate before a remainder of the first substrate was removed to form the portion of the first substrate. Another substrate may be attached to the portion of the first substrate, the portion of the first substrate being interposed between the polycrystalline table and the other substrate. Earth-boring tools may include such cutting elements secured to bodies of the earth-boring tools. Bearings for earth-boring tools may include a polycrystalline table attached to a portion of a first substrate on which the polycrystalline table was formed, the polycrystalline table defining a contact surface.

Abstract: Earth-boring drill bits may include a bit body including blades extending radially over a face of the earth-boring drill bit and cutting elements attached to each blade. Only cutting elements including planar cutting faces may be attached to at least one of the blades. Only cutting elements including nonplanar cutting faces may be attached to at least another of the blades. Only cutting elements including planar cutting faces or only cutting elements including nonplanar cutting faces may be attached to each of the blades. Only cutting elements including nonplanar cutting faces may be attached to a number of the blades that may be unequal to a number of the blades to which only cutting elements comprising planar cutting faces may be attached.

Abstract: A cutting element comprises a supporting substrate, and a polycrystalline compact attached to an end of the supporting substrate. The polycrystalline compact comprises a region adjacent the end of the supporting substrate, and another region at least substantially laterally circumscribing the region and having lesser permeability than the region. A method of forming a cutting element, and an earth-boring tool are also described.

Abstract: Methods of forming inserts for earth-boring tools include providing a material in a pattern adjacent a strip, arranging a plurality of superabrasive particles proximate the pattern, and securing at least some of the plurality of superabrasive particles to the strip. The material is configured to attract or secure the plurality of superabrasive particles. Some methods may include imparting like charges to each of a plurality of superabrasive particles, placing the plurality of superabrasive particles over a strip, and securing the superabrasive particles to the strip. In some methods, a first plurality of superabrasive particles may be placed in an array between a first strip and a second strip. A second plurality of superabrasive particles may be placed in an array between the second strip and a third strip. Methods of forming earth-boring rotary drill bits include forming an insert and securing the insert to a body of the bit.

Abstract: Cutting elements for use with earth-boring tools include a cutting table having at least two sections where a boundary between the at least two sections is at least partially defined by a discontinuity formed in the cutting table. Earth-boring tools including a tool body and a plurality of cutting elements carried by the tool body. The cutting elements include a cutting table secured to a substrate. The cutting table includes a plurality of adjacent sections, each having a discrete cutting edge where at least one section is configured to be selectively detached from the substrate in order to substantially expose a cutting edge of an adjacent section. Methods for fabricating cutting elements for use with an earth-boring tool including forming a cutting table comprising a plurality of adjacent sections.