A transition metal catalyst free polycrystalline diamond compact having enhanced thermal stability is disclosed herein. The diamond compact may be attached to a hard metal substrate. The polycrystalline diamond body includes a plurality of diamond grains bonded to adjacent diamond grains by diamond-to-diamond bonds. Sintering of the PCD and the formation of diamond-to-diamond bonding is achieved by transforming graphene treated diamond crystals that are blended with non-metal additives at high pressure and high temperature into a diamond compact that is free of transition metal catalysts. Non-metal additives include vitreous and other non-equilibrium forms of carbon as well as Sr-, K- and Ca-containing carbon sources.

Roller cutters comprise a diamond-bonded body joined to an infiltration substrate. An extension is joined to the substrate and includes first section having a diameter sized the same as the substrate, and an integral second section having a diameter smaller than the substrate. The extension is joined to the substrate during an HPHT process. The first section has a thickness greater than that of the infiltration substrate. The second section has an axial length greater than the combined thickness of the substrate and the first section. The extension has a strength and/or toughness greater than the substrate as a result of its material composition, e.g., the amount of binder phase material and/or the size of hard phase material. The roller cutter is rotatably disposed within a pocket internal cavity, wherein the pocket is attached to a drill bit.

Methods for forming cutting elements comprising polycrystalline materials, methods for forming polycrystalline compacts for cutting elements of a drilling tool, methods for forming polycrystalline diamond compacts, and resulting polycrystalline compacts and cutting elements are disclosed. Grains of a hard material are introduced to a press and subjected to a high-pressure, high-temperature (HPHT) process to sinter the grains. The system conditions (i.e., temperature and pressure) are then adjusted past a phase or state change point, after which, at least one of the system conditions is held during an anneal stage before the system conditions are adjusted to final levels. The resulting compacts and cutting elements may therefore include inter-granularly bonded hard material grains with a more stable microstructure (e.g., less stressed microstructure) than a polycrystalline compact and cutting element formed without an anneal stage during the HPHT process.

Polycrystalline diamond constructions are formed from a mixture of diamond grains including a first volume of fine-sized diamond grains, and a second volume of coarse-sized diamond grains. The fine-sized diamond grains are partially graphitized, and the coarse-sized diamond grains are not graphitized. The mixture of diamond grains is subjected to high pressure/high temperature sintering process conditions in the presence of a sintering aid thereby forming polycrystalline diamond. Contact areas between coarse-sized diamond grains in the polycrystalline diamond construction are substantially free of graphite.

A superabrasive compact and a method of making the superabrasive compact are disclosed. A method of making a superabrasive compact comprises steps of providing a plurality of superabrasive particles having a particle size distribution with a first ratio (d50)/(d50 principle particles) ranging from about 0.86 to about 0.92; providing a support to the plurality of superabrasive particles; and subjecting the support and the plurality of superabrasive particles to conditions of an elevated temperature and pressure suitable for producing the polycrystalline superabrasive compact.

A polycrystalline superhard construction comprises a body of polycrystalline superhard material, and a substrate of hard material bonded thereto along an interface. The body of polycrystalline superhard material comprises a first region abutting the substrate along the interface and a second region bonded to the first region. The second region defines a rake face, a cutting edge, a chamfer and at least a part of a flank face, the cutting edge being defined by an edge of the flank face joined to the chamfer, the chamfer extending between the cutting edge and the rake face. The height of the chamfer in a plane parallel to the plane through which the longitudinal axis of the polycrystalline superhard construction extends is less than the thickness of the second region. The first region comprises a material having coarser grains than the second region. There is also disclosed a method of making the same.

The present disclosure relates to cutting elements incorporating polycrystalline diamond bodies used for subterranean drilling applications, and more particularly, to polycrystalline diamond bodies having a high diamond content which are configured to provide improved properties of thermal stability and wear resistance, while maintaining a desired degree of impact resistance, when compared to prior polycrystalline diamond bodies. In various embodiments disclosed herein, a cutting element with high diamond content includes a modified PCD structure and/or a modified interface (between the PCD body and a substrate), to provide superior performance.

An assembly for High Pressure High Temperature (HPHT) synthesis of a superhard material. The assembly comprises a container comprising a first metal. A closure also comprising the first metal is sealed to the container using a sealant material. The sealant material comprises a second metal, the seal comprising a composition of the first and second metals formable below the melting point of the second metal. The container contains superhard material.

A polycrystalline compact includes diamond, cubic boron nitride, and at least one hard material, which may be aluminum nitride, gallium nitride, silicon nitride, titanium nitride, silicon carbide, titanium carbide, titanium boride, titanium diboride, and/or aluminum boride. The diamond, the cubic boron nitride, and the hard material are intermixed and interbonded to form a polycrystalline material. An earth-boring tool includes a bit body and a polycrystalline diamond compact secured to the bit body. Methods of fabricating polycrystalline compacts include forming a mixture comprising diamond, non-cubic boron nitride, and a metal or semimetal; encapsulating the mixture in a container; and subjecting the encapsulated mixture to high-pressure and high-temperature conditions to form a polycrystalline material.

Embodiments relate to polycrystalline diamond compacts (PDCs) and methods of manufacturing such PDCs in which an at least partially leached polycrystalline diamond (PCD) table is infiltrated with a low viscosity cobalt-based alloy infiltrant. In an embodiment, a method includes forming a PCD table in the presence of a metal-solvent catalyst in a first high-pressure/high-temperature (HPHT) process. The method includes at least partially leaching the PCD table to remove at least a portion of the metal-solvent catalyst therefrom to form an at least partially leached PCD table. The method includes subjecting the at least partially leached PCD table and a substrate to a second HPHT process effective to at least partially infiltrate the at least partially leached PCD table with a cobalt-based alloy infiltrant having a composition at or near a eutectic composition of the cobalt-based alloy infiltrant.