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.

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 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.

Grains of superabrasive material may be infiltrated with a molten metal alloy at a relatively low temperature, and the molten metal alloy may be solidified within interstitial spaces between the grains of superabrasive material to form a solid metal alloy having the grains of superabrasive material embedded therein. The solid metal alloy with the grains of superabrasive material embedded therein may be subjected to a high pressure and high temperature process to form a polycrystalline superabrasive material. A polycrystalline superabrasive material also may be formed by depositing material on surfaces of grains of superabrasive material in a chemical vapor infiltration process to form a porous body, which then may be subjected to a high pressure and high temperature process. Polycrystalline compacts and cutting elements including such compacts may be formed using such methods.

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. A resulting polycrystalline compact may include a high density of inter-granularly bonded hard material with a minimized amount of catalyst material, and may provide improved thermal stability, wear resistance, toughness, and behavior during use of a cutting element incorporating the polycrystalline compact.

Superabrasive tools and methods for the making thereof are disclosed and described. In one aspect, superabrasive particles are chemically bonded to a matrix support material according to a predetermined pattern by a braze alloy. The brazing alloy may be provided as a powder, thin sheet, or sheet of amorphous alloy. A template having a plurality of apertures arranged in a predetermined pattern may be used to place the superabrasive particles on a given substrate or matrix support material.

Grains of superabrasive material may be infiltrated with a molten metal alloy at a relatively low temperature, and the molten metal alloy may be solidified within interstitial spaces between the grains of superabrasive material to form a solid metal alloy having the grains of superabrasive material embedded therein. The solid metal alloy with the grains of superabrasive material embedded therein may be subjected to a high pressure and high temperature process to form a polycrystalline superabrasive material. A polycrystalline superabrasive material also may be formed by depositing material on surfaces of grains of superabrasive material in a chemical vapor infiltration process to form a porous body, which then may be subjected to a high pressure and high temperature process. Polycrystalline compacts and cutting elements including such compacts may be formed using such methods.

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. A resulting polycrystalline compact may include a high density of inter-granularly bonded hard material with a minimized amount of catalyst material, and may provide improved thermal stability, wear resistance, toughness, and behavior during use of a cutting element incorporating the polycrystalline compact.

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.