Abstract: 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 % Cr3C2.

Abstract: A polycrystalline super hard construction has a body of polycrystalline diamond material with a working surface, a first region substantially free of a solvent/catalysing material extending a depth from the working surface into the body of PCD material, and a second region remote from the working surface that includes solvent/catalysing material. The first and second regions are joined along a boundary. A chamfer extends between the working surface and a peripheral side surface of the body of PCD material. The distance from the midpoint of the chamfer to the boundary of the first and second regions along a plane substantially perpendicular to the plane in which the chamfer extends is at least X divided by two, where X is 0.8 times the thickness of the body of PCD material.

Abstract: 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 % Cr3C2.