A polycrystalline diamond (PCD) composite compact element has a body of polycrystalline diamond material and a cemented carbide substrate bonded to the body of polycrystalline material along an interface. The cemented carbide substrate has tungsten carbide particles bonded together by a binder material, the binder material including an alloy of Co, Ni and Cr. The tungsten carbide particles form at least 70 weight percent and at most 95 weight percent of the substrate and the binder material has between about 60 to 90 wt. % Ni, between about 10 to 40 wt. % Co, and about 0.25 to 1.0 wt % Cr.sub.3C.sub.2.

A polycrystalline diamond (PCD) composite compact element has a body of polycrystalline diamond material and a cemented carbide substrate bonded to the body of polycrystalline material along an interface. The cemented carbide substrate has tungsten carbide particles bonded together by a binder material, the binder material including an alloy of Co, Ni and Cr. The tungsten carbide particles form at least 70 weight percent and at most 95 weight percent of the substrate and the binder material has between about 60 to 90 wt. % Ni, between about 10 to 40 wt. % Co, and about 0.25 to 1.0 wt % Cr.sub.3C.sub.2.

A method for sintering includes loading a tool material into a resistance heating element within a HPHT press and heating the resistance heating element at a first axial portion to a control temperature, where a temperature difference is measured between the control temperature and a second temperature measured at a distal axial portion along the resistance heating element, wherein a difference between the control temperature and the second temperature ranges between about 5 percent to about 11 percent of the control temperature.

A tool having a cutting edge that includes a sintered body containing cubic boron nitride. The sintered body integrally and inseparably includes an inner region and a binder phase enriched layer formed on at least part of a surface of the inner region. The inner region includes: 15-90 volume % of cubic boron nitride; and 10-85 volume % of a mixture of a binder phase and impurities. The binder phase enriched layer includes: 90-100 volume % of the binder phase and impurities mixture; and 0-10 volume % of cubic boron nitride; and the binder phase contains at least one kind selected from the group consisting of: at least one element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Al, Co, Ni and Si; and a compound of the element and at least one element selected from the group consisting of C, N, O and B.

A polycrystalline cubic boron nitride, PCBN, material is provided. The material comprises between 30 and 90 weight percent cubic boron nitride (cBN) and a matrix material in which the cBN particles are dispersed. The matrix material comprises particles of an aluminium compound; the matrix material particles having a d50 when measured using a linear intercept technique of no more than 100 nm.

A cutting element has a thermally stable polycrystalline diamond layer formed on an upper side of a polycrystalline diamond layer and having a cutting face opposite the polycrystalline diamond layer, a transition layer on a side of the polycrystalline diamond layer opposite the thermally stable polycrystalline diamond layer, and a non-planar interface between the transition layer and the polycrystalline diamond layer, the non-planar interface having a perimeter exposed around a side surface of the cutting element and encircling an interior of the non-planar interface, and an uppermost portion of the perimeter being a distance from the cutting face greater than an axial distance between the cutting face and the interior.

A sheet-shaped aluminum-diamond composite containing a prescribed amount of a diamond powder wherein a first and second peak in a volumetric distribution of particle sizes occurs at 5-25 m and 55-195 m, and a ratio between an area of a volumetric distribution of particle sizes of 1-35 m and 45-205 m is from 1:9 to 4:6, the composite including an aluminum-containing metal as the balance, wherein the composite is covered, on both main surfaces, with a surface layer having prescribed film thicknesses and containing 80 vol % or more of an aluminum-containing metal, two or more Ni-containing layers are formed on at least the surface layer, the Ni-containing layers being such that a first and second layer from the surface layer side are amorphous Ni alloy layers having prescribed thicknesses, and an Au layer having a prescribed thickness is formed as an outermost layer.

Polycrystalline diamond compacts having interstitial diamonds and methods of forming polycrystalline diamond compact shaving interstitial diamonds with a quench cycle are described herein. In one embodiment, a polycrystalline diamond compact includes a substrate and a polycrystalline diamond body attached to the substrate. The polycrystalline diamond body includes a plurality of inter-bonded diamond grains that are attached to one another in an interconnected network of diamond grains and interstitial pockets between the inter-bonded diamond grains, and a plurality of interstitial diamond grains that are positioned in the interstitial pockets. Each of the plurality of interstitial diamond grains are attached to a single diamond grain of the interconnected network of diamond grains or other interstitial diamond grains.

A superhard polycrystalline construction comprises a body of polycrystalline superhard material comprising a superhard phase, and a second phase dispersed in the superhard phase, the superhard phase comprising a plurality of inter-bonded superhard grains. The second phase comprises particles or grains that do not chemically react with the superhard grains, and/or do not inter-grow, and form between around 1 to 30 volume % or wt % of the body of polycrystalline superhard material.

A cutting element comprises a supporting substrate, and a cutting table attached to an end of the supporting substrate. The cutting table comprises inter-bonded diamond particles, and a thermally stable material within interstitial spaces between the inter-bonded diamond particles. The thermally stable material comprises a carbide precipitate having the general chemical formula, A.sub.3XZ.sub.n-1, where A comprises one or more of Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Ac, Th, Pa, and U; X comprises one or more of Al, Ga, Sn, Be, Bi, Te, Sb, Se, As, Ge, Si, B, and P; Z comprises C; and n is greater than or equal to 0 and less than or equal to 0.75. A method of forming a cutting element, an earth-boring tool, a supporting substrate, and a method of forming a supporting substrate are also described.