A cBN sintered material comprising cBN particles and a binder phase, in which the binder phase contains AlN and AlB.sub.2, a content proportion of cBN particles is 70 to 97 vol %, cBN sintered material has a volume resistivity up to 5×10.sup.−3 Ωcm, a rate of a peak intensity derived from Al with respect to a peak intensity derived from cBN particles is less than 1.0%, cBN particles include fine particles and coarse particles, coarse particles optionally include ultra-coarse particles, with respect to the entire cBN particles, a content proportion α of fine particles is from 10 vol %, a content proportion β of coarse particles is from 30 vol %, a content proportion γ of ultra-coarse particles is 25 vol % or less, and a total of the content proportion α of fine particles and the content proportion β of coarse particles is 50 to 100 vol %.

Methods for large-scale additive manufacturing of high-strength boron nitride nanotubes (BNNT) / aluminum (Al) (e.g., reinforced Al alloy) metal matrix composites (MMCs) (BNNT/A1 MMCs), as well as the BNNT/A1 MMCs produced by the large-scale additive manufacturing methods, are provided. A combination of ultrasonication and spray drying techniques can produce good BNNT/Al alloy feedstock powders, which can be used in a cold spraying process.

A cutting element for an earth-boring drill bit may include a thermally stable cutting table comprising a polycrystalline diamond material. The polycrystalline diamond material may consist essentially of a matrix of diamond particles bonded to one another and a silicon, silicon carbide, or silicon and silicon carbide material located within interstitial spaces among interbonded diamond particles of the matrix of diamond particles. The cutting table may be at least substantially free of Group VIII metal or alloy catalyst material. The cutting element may further include a substrate and an adhesion material between and bonded to the cutting table and the substrate. The adhesion material may include diamond particles bonded to one another and to the cutting table and the substrate after formation of the preformed cutting table.

A cutting element for an earth-boring drill bit may include a thermally stable cutting table comprising a polycrystalline diamond material. The polycrystalline diamond material may consist essentially of a matrix of diamond particles bonded to one another and a silicon, silicon carbide, or silicon and silicon carbide material located within interstitial spaces among interbonded diamond particles of the matrix of diamond particles. The cutting table may be at least substantially free of Group VIII metal or alloy catalyst material. The cutting element may further include a substrate and an adhesion material between and bonded to the cutting table and the substrate. The adhesion material may include diamond particles bonded to one another and to the cutting table and the substrate after formation of the preformed cutting table.

The present disclosure provides a sintering assembly and a polycrystalline diamond compact (PDC) including a acid-labile leach-enhancing material, a PDC including cavities formed by removal of an acid-labile leach-enhancing material, and a method of forming a leached PDC using an acid-labile leach-enhancing material. The present disclosure further includes drill bits using PDCs formed suing an acid-labile leach-enhancing material.

The present disclosure provides a sintering assembly and a polycrystalline diamond compact (PDC) including a acid-labile leach-enhancing material, a PDC including cavities formed by removal of an acid-labile leach-enhancing material, and a method of forming a leached PDC using an acid-labile leach-enhancing material. The present disclosure further includes drill bits using PDCs formed suing an acid-labile leach-enhancing material.

The present disclosure provides a sintering assembly and a polycrystalline diamond compact (PDC) including a acid-labile leach-enhancing material, a PDC including cavities formed by removal of an acid-labile leach-enhancing material, and a method of forming a leached PDC using an acid-labile leach-enhancing material. The present disclosure further includes drill bits using PDCs formed suing an acid-labile leach-enhancing material.

A composite sintered material includes a plurality of diamond grains, a plurality of cubic boron nitride grains, and a remainder of a binder phase, wherein the binder phase includes cobalt, a content of the cubic boron nitride grains in the composite sintered material is more than or equal to 3 volume % and less than or equal to 40 volume %, and an average length of line segments extending across continuous cubic boron nitride grains in appropriately specified straight lines extending through the composite sintered material is less than or equal to a length three times as large as an average grain size of the cubic boron nitride grains.

A composite sintered material includes a plurality of diamond grains, a plurality of cubic boron nitride grains, and a remainder of a binder phase, wherein the binder phase includes cobalt, a content of the cubic boron nitride grains in the composite sintered material is more than or equal to 3 volume % and less than or equal to 40 volume %, and an average length of line segments extending across continuous cubic boron nitride grains in appropriately specified straight lines extending through the composite sintered material is less than or equal to a length three times as large as an average grain size of the cubic boron nitride grains.

The polycrystalline diamond compact cutter includes a diamond table and a carbide substrate. Different zones of the diamond table with relative thermal stability and toughness to each other are arranged for a particular cutting efficiency and working life. A thermally stable zone has a metal formation agent removed and forms a top outer ring. A base zone bonds to the carbide substrate on the bottom surface of the diamond table. An anchor zone sets between the thermally stable zone and the base zone, and an absorbing zone extends from the top surface to the base zone. The absorbing zone is circumscribed by the thermally stable zone and the anchor zone. The weight percentage metal content of the anchor zone is less than weight percentage metal content of the base zone. The weight percentage metal content of the base zone is less than weight percentage metal content of the absorbing zone.