Embodiments relate to polycrystalline diamond compacts (PDCs) that are less susceptible to liquid metal embrittlement damage due to the use of at least one transition layer between a polycrystalline diamond (PCD) layer and a substrate. In an embodiment, a PDC includes a PCD layer, a cemented carbide substrate, and at least one transition layer bonded to the substrate and the PCD layer. The at least one transition layer is formulated with a coefficient of thermal expansion (CTE) that is less than a CTE of the substrate and greater than a CTE of the PCD layer. At least a portion of the PCD layer includes diamond grains defining interstitial regions and a metal-solvent catalyst occupying at least a portion of the interstitial regions. The diamond grains and the catalyst collectively exhibit a coercivity of about 115 Oersteds or more and a specific magnetic saturation of about 15 Gauss.Math.cm.sup.3/grams or less.

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 single crystal diamond having a half width of an x-ray diffraction rocking curve of 20 seconds or less, a half width of a peak at a Raman shift of 1332 cm.sup.?1 to 1333 cm.sup.?1 (inclusive) in a Raman spectroscopic spectrum of 2.0 cm.sup.?1 or less, an etch pit density of 10,000/cm.sup.2 or less, a content of nitrogen based on number of atoms of 0.0001-0.1 ppm (inclusive), and a content of .sup.13C based on number of atoms of 0.01-1.0% (inclusive).

Embodiments relate to polycrystalline diamond compacts (PDCs) including a polycrystalline diamond (PCD) table having a diamond grain size distribution selected for improving performance and/or leachability. In an embodiment, a PDC includes a PCD table bonded to a substrate. The PCD table includes a plurality of diamond grains exhibiting diamond-to-diamond bonding therebetween. Other embodiments are directed to methods of forming PDCs, and various applications for such PDCs in rotary drill bits, bearing apparatuses, and wire-drawing dies.

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.

This disclosure relates to weldments useful as heat transfer tubes in refinery processes dealing with gas phase hydrocarbon process streams at high temperatures. This disclosure also relates to tubes that are useful in refinery processes dealing with gas phase hydrocarbon process streams at high temperatures. The weldments include a tubular member and at least one mixing element. The tubular member comprises an aluminum-containing alloy. The mixing element comprises an aluminum-containing alloy. The mixing element's aluminum-containing alloy can be the same as or different from the tubular member's aluminum-containing alloy. Other aspects of the disclosure relate to refinery processes dealing with gas phase hydrocarbon process streams at high temperatures which include such weldments.