Abstract: A superabrasive cutting element for use with a drill bit for drilling subterranean formations and having a superabrasive table, or cutting face, in which a conglomerate of superabrasive particles are dispersed and bonded, or sintered, and in which at least one exposed cutting region of the superabrasive table develops a rough, asperital surface for improving the cutting efficiency of the drill bit, particularly in but not limited to relatively hard, relatively nonabrasive formations. The superabrasive table may include superabasive particles of substantially differing size, quality or a combination of differing size and quality. A rotary drill bit including cutting elements embodying the present invention is also disclosed.

Abstract: This invention relates to a method of cutting, comprising the steps of: a) providing an abrasive cutting tool comprising: i) a substrate surface having a plurality of teeth extending therefrom, and ii) a single layer of abrasive grains chemically bonded to at least a portion of each tooth to define a plurality of cutting levels parallel to the substrate surface, the cutting levels comprising a first uppermost cutting level and a second uppermost cutting level, the grains having a predetermined concentration, size and toughness, b) moving the substrate surface in an intended direction of rotation, c) contacting the uppermost cutting level of at least one tooth to a workpiece at a point of contact, d) applying a constant force to the tool directed at the point of contact, wherein the constant force is sufficient to cut the workpiece, the strength of the bond is sufficient to resist peeling, the predetermined concentration, size and toughness of the plurality of grains are such that the grains of the uppe

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 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: 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 and a drill bit having such cutters for drilling subterranean formations including a superabrasive table formed on an end face of a supporting substrate, there being an interface between the table and the end face including a topographic configuration including at least one, and preferably a plurality of, annular arcuate surfaces centered about the centerline of the cutter and at least one recessed region or groove extending across a substantial portion of the end face. The topographic configuration of the end face is of an orientation and radial width sufficient to accommodate resultant loading of the cutting edge of the cutter throughout a variety of angles with vectors normal to the surface at a variety of angles such that at least one normal vector is aligned substantially parallel to the resultant loading on the cutting edge.

Abstract: An insert for a rolling cone earth-boring bit has a cylindrical base that interferingly presses into a mating hole formed in a cone of the bit. The insert has a convex end that extends from the base. A polycrystalline diamond cap is bonded to the convex end. The body is formed of at least two layers of carbide material having different mechanical properties, particularly a different modulus of elasticity. The first layer may have a metallic binder with a lesser percentage than the binder of the second layer to reduce the stress at the interface between the first layer and the diamond cap. The layers may have different average carbide grain sizes, with finer average grain sizes adjoining the diamond cap. Further, the layers may have different binders, with cobalt being the binder in the layer adjoining the diamond cap and either nickel or a nickel-cobalt alloy in another layer.

Abstract: An insert for a rolling cone earth-boring bit has a cylindrical base that interferingly presses into a mating hole formed in a cone of the bit. The insert has a convex end that extends from the base. A polycrystalline diamond cap is bonded to the convex end. The body is formed of at least two layers of carbide material having different mechanical properties, particularly a different modulus of elasticity. The first layer may have a metallic binder with a lesser percentage than the binder of the second layer to reduces the stress at the interface between the first layer and the diamond cap. The layers may have different average carbide average grain sizes, with finer average grain sizes adjoining the diamond cap. Further, the layers may have different binders, with cobalt being the binder in the layer adjoining the diamond cap and either nickel or a nickel-cobalt alloy in another layer.

Abstract: A bond for a single layer metal bond abrasive tool can be easily chemically and electrochemically stripped from the metal core of a recovered used tool to facilitate reuse of the core. Relative to conventionally bonded tools, the speed of stripping the novel bond is quick, and the stripped core has a smooth, clean surface which needs only minimal mechanical repair prior to reuse. In one aspect, the novel bond is a quaternary bond composition consisting essentially of copper, tin, titanium and silver. The powder components can be used dry or mixed with a fugitive liquid binder as a paste. The novel bond can be brazed at lower temperature than copper/tin/titanium bonds prepared otherwise. The bond composition forms a good melt at braze temperature that flows smoothly, evenly over a tool preform and provides consistent quality bonding of abrasive from tool to tool.

Abstract: A bond for a single layer metal bond abrasive tool can be easily chemically and electrochemically stripped from the metal core of a recovered used tool to facilitate reuse of the core. Relative to conventionally bonded tools, the speed of stripping the novel bond is quick, and the stripped core has a smooth, clean surface which needs only minimal mechanical repair prior to reuse. In one aspect, the novel bond consists essentially of a ternary bond composition of copper, tin and titanium, in which the copper and tin are pre-alloyed and the pre-alloy and titanium component are incorporated in the bond composition as fine particle size powders. In another aspect, the bond is a quaternary bond composition consisting essentially of copper, tin, titanium and silver. The powder components can be used dry or mixed with a fugitive liquid binder as a paste. The novel bond can be brazed at lower temperature than copper/tin/titanium bonds prepared otherwise.

Abstract: Textured indentations in the cutting surface of the core of a cutting tool are designed to accommodate a single layer of superabrasive grain. The superabrasive grain contained in these textured indentations is thereby oriented during metal bond brazing such that a cutting edge of the superabrasive grain is oriented outward from the plane of the cutting surface of the core. Enhanced bond life, cutting performance and tool life are achieved.