A cutting tool which may be used in machining various material may include a body and one or more cutting elements associated therewith. In one example, the cutting element(s) may comprise a superhard table, such as a polycrystalline diamond table. In some embodiments, the polycrystalline diamond table may have a diamond density of approximately 95 percent volume or greater. In some embodiments, the thickness of the superhard table may be approximately 0.15 inch. In some embodiments, the superhard table may include a chip breaking feature or structure. Methods of shaping, finishing or otherwise machining materials are also provided, including the machining of materials comprising titanium.

An embodiment of a PCD insert comprises an embodiment of a PCD element joined to a cemented carbide substrate at an interface. The PCD element has internal diamond surfaces defining interstices between them. The PCD element comprises a masked or passivated region and an unmasked or unpassivated region, the unmasked or unpassivated region defining a boundary with the substrate, the boundary being the interface. At least some of the internal diamond surfaces of the masked or passivated region contact a mask or passivation medium, and some or all of the interstices of the masked or passivated region and of the unmasked or unpassivated region are at least partially filled with an infiltrant material.

An embodiment of a PCD insert comprises an embodiment of a PCD element joined to a cemented carbide substrate at an interface. The PCD element has internal diamond surfaces defining interstices between them. The PCD element comprises a masked or passivated region and an unmasked or unpassivated region, the unmasked or unpassivated region defining a boundary with the substrate, the boundary being the interface. At least some of the internal diamond surfaces of the masked or passivated region contact a mask or passivation medium, and some or all of the interstices of the masked or passivated region and of the unmasked or unpassivated region are at least partially filled with an infiltrant material.

An embodiment of a PCD insert comprises an embodiment of a PCD element joined to a cemented carbide substrate at an interface. The PCD element has internal diamond surfaces defining interstices between them. The PCD element comprises a masked or passivated region and an unmasked or unpassivated region, the unmasked or unpassivated region defining a boundary with the substrate, the boundary being the interface. At least some of the internal diamond surfaces of the masked or passivated region contact a mask or passivation medium, and some or all of the interstices of the masked or passivated region and of the unmasked or unpassivated region are at least partially filled with an infiltrant material.

A method of forming a cutting element for an earth-boring tool may include directing at least one energy beam at a surface of a volume of polycrystalline superabrasive material including interstitial material disposed in regions between inter-bonded grains of polycrystalline superabrasive material. The method includes ablating the interstitial material with the at least one energy beam such that at least a portion of the interstitial material is removed from a first region of the volume of polycrystalline superabrasive material without any substantial degradation of the inter-bonded grains of superabrasive material or of bonds thereof in the first region.

A method of forming a cutting element for an earth-boring tool may include directing at least one energy beam at a surface of a volume of polycrystalline superabrasive material including interstitial material disposed in regions between inter-bonded grains of polycrystalline superabrasive material. The method includes ablating the interstitial material with the at least one energy beam such that at least a portion of the interstitial material is removed from a first region of the volume of polycrystalline superabrasive material without any substantial degradation of the inter-bonded grains of superabrasive material or of bonds thereof in the first region.

The cubic boron nitride sintered material is a cubic boron nitride sintered material comprising: cubic boron nitride particles in an amount of 70 vol % or more and less than 100 vol %, and a bonding material, wherein the bonding material includes an aluminum compound, and includes cobalt as a constituent element; the cubic boron nitride sintered material has a first region in which a space between adjacent cubic boron nitride particles is 0.1 nm or more and 10 nm or less; and when the first region is analyzed by using an energy dispersive X-ray analyzer equipped with a transmission electron microscope, the atom % of aluminum in the first region is 0.1 or more.

Methods for forming a polycrystalline diamond compact (PDC) drill bit from catalyst-free synthesized polycrystalline diamonds are described. The polycrystalline diamonds are deposited within a mold. In some cases, a matrix body material is deposited within the mold, and an infiltration process is performed to bond the polycrystalline diamonds to the matrix body material to form the PDC drill bit. In some cases, a drill bit body is formed within the mold, and forming the drill bit body within the mold includes depositing a layer of matrix body material particles within the mold, depositing an adhesive ink within the mold, and curing the adhesive ink. In some cases, a sintering process is performed after forming the drill bit body to remove at least a portion of the adhesive ink and increase a density of the drill bit body to form the PDC drill bit.

A superhard polycrystalline construction comprises a body of polycrystalline superhard material comprising a superhard phase, and a non-superhard phase dispersed in the superhard phase, the superhard phase comprising a plurality of inter-bonded superhard grains. The non-superhard phase comprises particles or grains that do not chemically react with the superhard grains and form less than around 10 volume % of the body of polycrystalline superhard material. There is also disclosed a method of forming such a superhard polycrystalline construction.

A superhard polycrystalline construction comprises a body of polycrystalline superhard material comprising a superhard phase, and a non-superhard phase dispersed in the superhard phase, the superhard phase comprising a plurality of inter-bonded superhard grains. The non-superhard phase comprises particles or grains that do not chemically react with the superhard grains and form less than around 10 volume % of the body of polycrystalline superhard material. There is also disclosed a method of forming such a superhard polycrystalline construction.