Abstract: A cutting element for an earth boring bit, wherein the PDC layer of the cutting element has a flat on a periphery thereof terminating longitudinally at en edge spaced from of the cutting face of the PDC layer. A chamfer adjacent the cutting face desirably has a length that exceeds its depth. Embodiments include a chamfer along the entire circumference of the cutting element, multiple step-wise, radially adjacent chamfers, and multiple circumferentially spaced portions of the uppermost radius of the PDC layer of the cutting element that each includes a chamfer with an associated flat. An embodiment including a flat terminating at a radial edge with the cutting face of a PDC layer is also disclosed, as are drill bits incorporating embodiments of the cutting elements of the invention and a method of forming the cutting elements.

Abstract: An abrasive-impregnated cutting structure for use in drilling a subterranean formation is disclosed. The abrasive-impregnated cutting structure may comprise a plurality of abrasive particles dispersed within a substantially continuous matrix, wherein the abrasive-impregnated cutting structure exhibits an anisotropic wear resistance. One or more of the amount, average size, composition, properties, shape, quality, strength, and concentration of the abrasive particles may vary within the abrasive-impregnated cutting structure. Anisotropic wear resistance may relate to a selected direction, such as, for example, one or more of an expected direction of engagement of the abrasive-impregnated cutting structure with the subterranean formation and an anticipated wear direction. Anisotropic wear resistance of an abrasive-impregnated cutting structure may be configured for forming or retaining a formation-engaging leading edge thereof.

Abstract: A drill bit or milling tool includes a bit body on which a plurality of cutting elements are disposed. At least some of the plurality of cutting elements include a diamond table and a superabrasive material non-reactive with iron-based materials disposed over at least a portion of an exterior surface of the diamond table. The diamond table is suitable for drilling through a subterranean formation and the non-reactive superabrasive material is suitable for drilling through a casing or casing-associated component comprising an iron-based material and disposed within the subterranean formation. The diamond table may comprise a PDC and the non-reactive superabrasive material may comprise cubic boron nitride.

Abstract: An earth-boring bit has a mechanical face seal assembly with PCD faces. The bit has a bearing shaft with a cone rotatably mounted on the bearing shaft. The seal locates between the bearing shaft and the cone for sealing lubricant therein. The seal includes at least one rigid seal ring having a cemented carbide body and an annular PCD face located on it. The mating face may also be of a PCD material. The cemented carbide body contains a binder that migrates into the PCD face while the PCD face is being formed. A binder-free region is leached on the surface of the PCD face.

Abstract: A cutting element for a rotary drill bit that has a superabrasive member joined to a substrate at a three-dimensional interface is disclosed. The interface of the cutting element preferably incorporates a first ring pattern comprising a plurality of circumferentially arranged raised sections which are separated by a plurality of radially extending grooves. Also, the interface configuration may include at least a second ring pattern comprising a plurality of circumferentially arranged raised sections which are separated by a plurality of radially extending grooves. Radially adjacent ring patterns may substantially circumferentially overlap with one another. An interface of a cutting element including at least one ring pattern having an odd number of sections is also disclosed. Further, rotary drill bits including at least one such cutting element are disclosed.

Abstract: An earth-boring bit has a seal assembly with a seal face having a DLC coating. The seal assembly locates between a bearing pin and a cone of the bit. The seal assembly has at least one rigid ring that rotates against a mating surface. The DLC coating is diamond-like carbon that may be coated by different processes onto either the ring, the mating surface, or both.

Abstract: A superabrasive cutting element including a diamond or other superabrasive material table having a peripheral cutting edge defined by at least two adjacent chamfers having an arcuate surface substantially tangent to each of the at least two chamfers interposed therebetween. Methods of producing such superabrasive cutting elements and drill bits equipped with such superabrasive cutting elements are also disclosed.

Abstract: A cutting element for a drill bit used in drilling subterranean formations is formed with an internal chamber or passage for the flow of drilling fluid therethrough. The cutting element includes a substrate having at least one internal passage, and prior to attaching a superabrasive table thereto, the at least one internal passage is filled with a removable, substantially incompressible filler material. Attachment or bonding of the superabrasive table to the substrate under high temperature and high pressure is accomplished without significant distortion of the shape and size of the internal passage. The filler material may be a crystalline salt such as sodium chloride or halite, which is removable by dissolution in water, or may be boron nitride or a volcanic material such as Pyrofolyte material which is mechanically removable.

Abstract: A superabrasive cutting element including a diamond or other superabrasive material table having a peripheral cutting edge defined by at least two adjacent chamfers having an arcuate surface substantially tangent to each of the at least two chamfers interposed therebetween. Methods of producing such superabrasive cutting elements and drill bits equipped with such superabrasive cutting elements are also disclosed.

Abstract: The residual stresses that are experienced in polycrystalline diamond cutters, which lead to cutter failure, can be effectively modified by selectively thinning the carbide substrate subsequent to high temperature, high pressure (sinter) processing, by selectively varying the material constituents of the carbide substrate, by subjecting the PDC cutter to an annealing process during sintering, by subjecting the formed PDC cutter to a post-process stress relief anneal, or a combination of those means.

Abstract: A superabrasive cutting element including a diamond or other superabrasive material table having a peripheral cutting edge defined by at least two adjacent chamfers having an arcuate surface substantially tangent to each of the at least two chamfers interposed therebetween. Methods of producing such superabrasive cutting elements and drill bits equipped with such superabrasive cutting elements are also disclosed.

Abstract: A cutting element for a drill bit used in drilling subterranean formations is formed with an internal chamber or passage for the flow of drilling fluid therethrough. The cutting element includes a substrate having at least one internal passage, and prior to attaching a superabrasive table thereto, the at least one internal passage is filled with a removable, substantially incompressible filler material. Attachment or bonding of the superabrasive table to the substrate under high temperature and high pressure is accomplished without significant distortion of the shape and size of the internal passage. The filler material may be a crystalline salt such as sodium chloride or halite, which is removable by dissolution in water, or may be boron nitride or a volcanic material such as Pyrofolyte material which is mechanically removable.

Abstract: A cutter for a drill bit has a superabrasive member joined to a substrate at a three-dimensional interface. The three-dimensional interface comprises a protrusive pattern of interconnected elements comprising projections of the superabrasive member into the substrate and vice versa. The protrusive pattern comprises at least one generally annular member intersected by a series of generally radially extending members for distributing stresses along the interface, enhancing compressive strength, and enabling optimization of the magnitudes and locations of beneficial residual stresses in the superabrasive member and in the vicinity of the substrate.

Abstract: An earth-boring bit has a seal assembly with a seal face having a DLC coating. The seal assembly locates between a bearing pin and a cone of the bit. The seal assembly has at least one rigid ring that rotates against a mating surface. The DLC coating is diamond-like carbon that may be coated by different processes onto either the ring, the mating surface, or both.

Abstract: An earth-boring bit has a mechanical face seal assembly with PCD faces. The bit has a bearing shaft with a cone rotatably mounted on the bearing shaft. The seal locates between the bearing shaft and the cone for sealing lubricant therein. The seal includes at least one rigid seal ring having a carbide body and an annular PCD face located on it. The mating face may also be of a PCD material.

Abstract: The cutting element including a cutting element for a drill bit used in drilling subterranean formations is formed with an internal chamber or passage for the flow of drilling fluid therethrough. A substrate having at least one internal passage, and prior to attaching a superabrasive table thereto, the at least one internal passage is filled with a removable substantially incompressible filler material. Attachment or bonding of the superabrasive table to the substrate under high temperature and high pressure is accomplished without significant distortion of the shape and size of the internal passage. The filler material may be a crystalline salt such as sodium chloride or halite, which is removable by dissolution in water, or may be boron nitride or a volcanic material such as Pyrofolyte material which is mechanically removable.

Abstract: A cutter for a drill bit has a superabrasive member joined to a substrate at a three-dimensional interface. The three-dimensional interface comprises a protrusive pattern of interconnected elements comprising projections of the superabrasive member into the substrate and vice versa. The protrusive pattern comprises at least one generally annular member intersected by a series of generally radially extending members for distributing stresses along the interface, enhancing compressive strength, and enabling optimization of the magnitudes and locations of beneficial residual stresses in the superabrasive member and in the vicinity of the substrate.

Abstract: A cutter for a drill bit has a superabrasive member joined to a substrate at a three-dimensional interface. The three-dimensional interface comprises a protrusive pattern of interconnected elements comprising projections of the superabrasive member into the substrate and vice versa. The protrusive pattern comprises at least one generally annular member intersected by a series of generally radially extending members for distributing stresses along the interface, enhancing compressive strength, and enabling optimization of the magnitudes and locations of beneficial residual stresses in the superabrasive member and in the vicinity of the substrate.

Abstract: An earth-boring bit has a mechanical face seal assembly with PCD faces. The bit has a bearing shaft with a cone rotatably mounted on the bearing shaft. The seal locates between the bearing shaft and the cone for sealing lubricant therein. The seal includes at least one rigid seal ring having a carbide body and an annular PCD face located on it. The mating face may also be of a PCD material.

Abstract: The residual stresses that are experienced in polycrystalline diamond cutters, which lead to cutter failure, can be effectively modified by selectively thinning the carbide substrate subsequent to high temperature, high pressure (sinter) processing, by selectively varying the material constituents of the carbide substrate, by subjecting the PDC cutter to an annealing process during sintering, by subjecting the formed PDC cutter to a post-process stress relief anneal, or a combination of those means.