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.

A method for treating a polycrystalline diamond material includes subjecting the polycrystalline diamond material to a leaching process and to a thermal decomposition process.

Polycrystalline diamond compacts (PDCs) include a polycrystalline diamond (PCD) table in which cobalt is alloyed with phosphorous to improve the thermal stability of the PCD table. For example, a PDC includes a substrate and a PCD table including an upper surface spaced from an interfacial surface that is bonded to the substrate. The PCD table includes a plurality of diamond grains defining a plurality of interstitial regions. The PCD table further includes an alloy comprising at least one Group VIII metal and phosphorous. The alloy is disposed in at least a portion of the plurality of interstitial regions.

A polycrystalline diamond structure comprises a first region and a second region adjacent the first region, the second region being bonded to the first region by intergrowth of diamond grains. The first region comprises a plurality of alternating strata or layers, each or one or more strata or layers in the first region having a thickness in the range of around 5 to 300 microns. The polycrystalline diamond (PCD) structure has a diamond content of at most about 95 percent of the volume of the PCD material, a binder content of at least about 5 percent of the volume of the PCD material, and one or more of the layers or strata in the first region comprise and/or the second region comprises diamond grains having a mean diamond grain contiguity of greater than about 60 percent and a standard deviation of less than about 2.2 percent. There is also disclosed a method of making such a polycrystalline diamond structure.

A method of producing a component of a composite of diamond and a binder, wherein a Hot Isostatic gas Pressure process (HIP) is used, includes the step of enclosing a de-bound green body having compacted diamond particles in an infiltrant. The method includes the further steps of enclosing the de-bound green body and the infiltrant in a Zr-capsule that has Zirconium as a main constituent and sealing the Zr-capsule, and applying a predetermined pressure-temperature cycle on the unit formed by the de-bound green body, infiltrant and capsule in which the infiltrant infiltrates the de-bound green body and the de-bound green body is further densified in the sense that the volume thereof is decreased.

A method of providing well-shaped diamond grains of at most about 100 microns in size. The method includes providing a synthesis assembly comprising a source of carbon material, a plurality of seed grains on which diamond material can crystallize, and solvent-catalyst material for promoting the crystallization of the diamond grains, and subjecting the synthesis assembly to a condition for growing the diamond grains. The synthesis condition is maintained long enough for at least about half of the carbon material to be converted into the diamond grains.

A method of forming polycrystalline diamond includes encapsulating diamond particles, carbon monoxide, and carbon dioxide in a container. The encapsulated diamond particles, carbon monoxide, and carbon dioxide are subjected to a pressure of at least 4.5 GPa and a temperature of at least 1,400 C. to form inter-granular bonds between the diamond particles. A cutting element includes polycrystalline diamond material comprising inter-bonded grains of diamond. The polycrystalline diamond material is substantially free of graphitic carbon and metallic compounds. The polycrystalline diamond material exhibits a density of at least about 3.49 g/cm.sup.3 and a modulus of at least about 1,000 GPa. An earth-boring tool may include such a cutting element secured to a body.

A capsule assembly for an ultra-high pressure furnace, comprising a containment tube having an interior side surface and defining a central longitudinal axis; a chamber suitable for accommodating a reaction assembly, a proximate and a distal end heater assembly, and a side heater assembly. When assembled, the chamber is contained within the containment tube and arranged longitudinally between the proximate and distal end heater assemblies. The side heater assembly is disposed adjacent the interior side surface and electrically connects the end heater assemblies with each other. Each end heater assembly has a respective peripheral side disposed adjacent the interior side surface Heat is produced in the chamber in response to an electric current flowing through the end and side heater assemblies. At least a proximate side heater barrier spaces apart the side heater assembly from at least the proximate end heater assembly, adjacent its peripheral side, operative to prevent a portion of the side heater assembly from intruding between the peripheral side of the proximate end heater assembly and the containment tube and short-circuiting at least part of the proximate end heater assembly, when the end heater assemblies move towards each other in response to a force applied by the ultra-high pressure furnace onto the capsule assembly along the central longitudinal axis.

A capsule assembly for an ultra-high pressure furnace, comprising a containment tube defining a central longitudinal axis, a chamber suitable for accommodating a reaction assembly, a proximate and a distal end heater assembly, and a side heater assembly. When assembled, the chamber and the side heater assembly are contained within the containment tube and arranged longitudinally between the proximate and distal end heater assemblies. Each end heater assembly comprises a respective conduction volume forming a respective electrical path through the end heat assembly. The side heater assembly electrically connects the respective conducting volumes to each other, and heat is produced in the chamber in response to an electric current flowing through the side heater assembly and the conducting volumes. At least the proximate end heater assembly comprises a first insulation component including an outer insulation volume. The conducting volume of at least the proximate end heater assembly includes an inner conducting volume, and the inner conducting volume is laterally spaced apart from the containment tube by the outer insulation volume.

A method of growing carbonaceous particles comprises depositing carbon from a carbon source, onto a particle nucleus, the particle nucleus being a carbon-containing material, an inorganic material, or a combination comprising at least one of the foregoing, and the carbon source comprising a saturated or unsaturated compound of C.sub.20 or less, the carbonaceous particles having a uniform particle size and particle size distribution. The method is useful for preparing polycrystalline diamond compacts (PDCs) by a high-pressure, high-temperature (HPHT) process.