A polycrystalline super hard construction comprises a body of polycrystalline super hard material and a substrate bonded to the body along an interface. The substrate a first end surface forming the interface, the first end surface comprising a projection extending from the body of the substrate into the body of super hard material towards the cutting face, the body of polycrystalline material extending around the projection. The body of polycrystalline material comprises a first region more thermally stable than a second region, the first region comprising an annular portion located around the projection, the second region extending between and bonding the first region to the substrate. The first region has a thickness from the cutting face along the peripheral side edge to the interface of at least around 3 mm and a portion of the projection has a thickness measured in a plane extending along the longitudinal axis of at least around 3 mm.

Polycrystalline compacts include a polycrystalline superabrasive material comprising a first plurality of grains of superabrasive material having a first average grain size and a second plurality of grains of superabrasive material having a second average grain size smaller than the first average grain size. The first plurality of grains is dispersed within a substantially continuous matrix of the second plurality of grains. Earth-boring tools may include a body and at least one polycrystalline compact attached thereto. Methods of forming polycrystalline compacts may include coating relatively larger grains of superabrasive material with relatively smaller grains of superabrasive material, forming a green structure comprising the coated grains, and sintering the green structure. Other methods include mixing diamond grains with a catalyst and subjecting the mixture to a pressure greater than about five gigapascals (5.0 GPa) and a temperature greater than about 1,300 C. to form a polycrystalline diamond compact.

Polycrystalline compacts include a polycrystalline superabrasive material comprising a first plurality of grains of superabrasive material having a first average grain size and a second plurality of grains of superabrasive material having a second average grain size smaller than the first average grain size. The first plurality of grains is dispersed within a substantially continuous matrix of the second plurality of grains. Earth-boring tools may include a body and at least one polycrystalline compact attached thereto. Methods of forming polycrystalline compacts may include coating relatively larger grains of superabrasive material with relatively smaller grains of superabrasive material, forming a green structure comprising the coated grains, and sintering the green structure. Other methods include mixing diamond grains with a catalyst and subjecting the mixture to a pressure greater than about five gigapascals (5.0 GPa) and a temperature greater than about 1,300 C. to form a polycrystalline diamond compact.

A cutting element may include a substrate and a volume of polycrystalline diamond material affixed to the substrate at an interface. The volume of polycrystalline diamond material may include a front cutting face with at least one substantially planar portion and at least one recess. The at least one recess may extend from a plane defined by the at least one substantially planar portion a first depth into the volume of polycrystalline diamond material in an axial direction parallel to a central axis of the cutting element. The volume of polycrystalline diamond material may comprise a region including a catalyst material. At least one region substantially free of the catalyst material may extend from the at least one substantially planar portion of the front cutting face a second depth into the volume of polycrystalline diamond material in the axial direction.

The present disclosure relates to a brazed superabrasive assemblies and method of producing brazed superabrasive assemblies. The brazed superabrasive assemblies may include a plurality of braze alloy layers that are positioned opposite a stress relieving layer. The stress relieving layer may have a solidus temperature that is greater than a solidus temperature of the plurality of braze alloy layers.

In an embodiment, a polycrystalline diamond compacts (PDC) includes a substrate and a polycrystalline diamond (PCD) table bonded to the substrate. The PCD table defines an upper surface and at least one peripheral surface. The PCD table includes a plurality of bonded diamond grains. The PCD table includes a first region adjacent to the substrate that includes a metallic constituent disposed interstitially between the bonded diamond grains thereof, and a leached second region extending inwardly from the upper surface and the at least one peripheral surface that is depleted of the metallic constituent. The leached second region exhibits a leach depth profile having a maximum leach depth that is measured from the upper surface. A leach depth of the leach depth profile decreases with lateral distance from a central axis of the PCD table and toward the at least one peripheral surface.

A PCD 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 comprising a plurality of alternating strata or layers, each stratum or layer having a thickness in the range of around 5 to 300 microns. The second region comprises a plurality of strata or layers, one or more strata or layers in the second region having a thickness greater than the thicknesses of the individual strata or layers in the first region. The alternating layers or strata in the first region comprise first layers or strata alternating with second layers or strata, the first layers or strata being in a state of residual compressive stress and the second layers or strata being in a state of residual tensile stress.

Magnetic sample holders for abrasive operations include an array of magnets embedded in a matrix material. Each magnet of the array is positioned between about 0 mm and about 4 mm from at least one adjacent magnet of the array. Exposed surfaces of the magnets of the array are coplanar with a planar working surface of the matrix material. Methods of forming a polycrystalline diamond compact element include magnetically securing an alloy sample to an array of magnets embedded in a matrix. Each of the magnets of the array is within about 4 mm of at least one adjacent magnet of the array. A portion of the alloy sample is abraded away, and the alloy sample is positioned proximate to diamond grains and a substrate. The alloy sample, diamond grains, and substrate are subjected to a high pressure/high temperature process to sinter the diamond grains.

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 cutters for rotary drill bits and methods of making the same are disclosed. A polycrystalline diamond compact includes a polycrystalline diamond body having a working surface, an interface surface, and a perimeter surface. The polycrystalline diamond compact also includes a substrate bonded to the polycrystalline diamond body along the interface surface. A non-diamond volume fraction of the polycrystalline diamond body is greater at the interface surface than at the working surface.