Abstract: A method of producing a free standing PCD comprises forming a mass of combined diamond particles and precursor compound(s) for the metals of the metallic network by suspending the diamond particles in a liquid, and crystallising and /or precip -itating the precursor compounds in the liquid. The mass is then removed from suspension by sedimentation and/or evaporation to form a dry powder of combined diamond particles and precursor compound(s). The powder is subjected to a heat treatment to disso -ciate and reduce the precursor compound(s) to form metal particles smaller in size than the diamond particles to provide a homogen -eous mass. This is then consolidated using isostatic compaction to form a homogeneous cohesive green body of a pre-selected size and 3-dimensional shape.

Abstract: A free standing PCD body comprises a PCD material formed of combination of intergrown diamond grains forming a diamond network and an interpenetrating metallic network, the PCD body not being attached to a second body or substrate formed of a different material. The diamond network is formed of diamond grains having a plurality of grain sizes, and comprises a grain size distribution having an average diamond grain size, wherein the largest component of the diamond grain size distribution is no greater than three times the average diamond grain size. The PCD material forming the free standing PCD body is homogeneous, such that the PCD body is spatially constant and invariant with respect to diamond network to metallic network volume ratio. The homogeneity is measured at a scale greater than ten times the average grain size and spans the dimension of the PCD body. The PCD material is also macroscopically residual stress free at said scale.

Abstract: The invention relates to a PCD composite compact element comprising a PCD structure integrally bonded at an interface to a cemented carbide substrate; the PCD structure comprising coherently bonded diamond grains having a mean size no greater than 15 microns; the cemented carbide substrate comprising carbide particles dispersed in a metallic binder, the carbide particles comprising a carbide compound of a metal; wherein the ratio of the amount of metallic binder to the amount of the metal at points in the substrate deviates from a mean value by at most 20 percent of the mean value.

Abstract: The invention relates to a PCD composite compact element comprising a PCD structure integrally bonded at an interface to a cemented carbide substrate; the PCD structure comprising coherently bonded diamond grains having a mean size no greater than 15 microns; the cemented carbide substrate comprising carbide particles dispersed in a metallic binder, the carbide particles comprising a carbide compound of a metal; wherein the ratio of the amount of metallic binder to the amount of the metal at points in the substrate deviates from a mean value by at most 20 percent of the mean value.

Abstract: A free standing PCD body comprises a PCD material formed of combination of intergrown diamond grains forming a diamond network and an interpenetrating metallic network, the PCD body not being attached to a second body or substrate formed of a different material. The diamond network is formed of diamond grains having a plurality of grain sizes, and comprises a grain size distribution having an average diamond grain size, wherein the largest component of the diamond grain size distribution is no greater than three times the average diamond grain size. The PCD material forming the free standing PCD body is homogeneous, such that the PCD body is spatially constant and invariant with respect to diamond network to metallic network volume ratio. The homogeneity is measured at a scale greater than ten times the average grain size and spans the dimension of the PCD body. The PCD material is also macroscopically residual stress free at said scale.

Abstract: A method of producing a free standing PCD comprises forming a mass of combined diamond particles and precursor compound(s) for the metals of the metallic network by suspending the diamond particles in a liquid, and crystallising and/or precipitating the precursor compounds in the liquid. The mass is then removed from suspension by sedimentation and/or evaporation to form a dry powder of combined diamond particles and precursor compound(s). The powder is subjected to a heat treatment to dissociate and reduce the precursor compound(s) to form metal particles smaller in size than the diamond particles to provide a homogeneous mass. This is then consolidated using isostatic compaction to form a homogeneous cohesive green body of a pre-selected size and 3-dimensional shape.

Abstract: Polycrystalline diamond abrasive elements made by incorporating low levels of at least one metal boride, the metal being selected from magnesium, calcium, aluminum, strontium, yttrium, zirconium, hafnium and chromium, and the rare earth metals, particularly cerium and lanthanum. The benefits of adding boron to polycrystalline diamond abrasive compacts are exploited together with simultaneously minimizing or eliminating the detrimental effects of the presence of oxygen.

Abstract: A cutter element for rock removal comprises a free standing PCD body (801, 1801) comprising one or more physical volumes (1702, 1703), the PCD material being invariant in terms of the diamond and metal network compositional ratio and metal elemental composition such that each physical volume does not differ to any other physical volume with respect to diamond and metal network compositional ratio and metal elemental composition. The PCD body has a functional working volume (803) forming in use the region which comes into contact with the rock. A functional support volume (804) extant in use and having a proximal free surface extends from the functional working volume.

Abstract: The invention relates to a PCD composite compact element comprising a PCD structure integrally bonded at an interface to a cemented carbide substrate; the PCD structure comprising coherently bonded diamond grains having a mean size no greater than 15 microns; the cemented carbide substrate comprising carbide particles dispersed in a metallic binder, the carbide particles comprising a carbide compound of a metal; wherein the ratio of the amount of metallic binder to the amount of the metal at points in the substrate deviates from a mean value by at most 20 percent of the mean value.

Abstract: A cutter element for rock removal comprises a free standing PCD body (801, 1801) comprising two or more physical volumes (1702, 1703) within the boundary of the PCD body, wherein adjacent physical volumes differ in one or more of diamond and metal network compositional ratio, metal elemental composition and diamond grain size distribution, a functional working volume (803) distal to the PCD body, the functional working volume forming in use a region which comes into contact with the rock. A functional support volume (804) extant in use and having a proximal free surface extends from the functional working volume. The PCD body has a shape having an aspect ratio such that the ratio of the length (ae) of the longest edge of the circumscribing rectangular parallelepiped of the overall PCD body to the largest width (ad) of the smallest rectangular face from which the functional working volume extends of the circumscribing rectangular parallelepiped, is greater than or equal to 1.

Abstract: A method of manufacturing polycrystalline abrasive elements consisting of micron, sub-micron or nano-sized ultrahard abrasives dispersed in micron, sub-micron or nano-sized matrix materials. A plurality of ultrahard abrasive particles having vitreophilic surfaces are coated with a matrix precursor material in a refined colloidal process and then treated to render them suitable for sintering. The matrix precursor material can be converted to an oxide, nitride, carbide, oxynitride, oxycarbide, or carbonitride, or an elemental form thereof. The coated ultrahard abrasive particles are consolidated and sintered at a pressure and temperature at which they are crystallographically or thermodynamically stable.

Abstract: A superhard structure comprises a body of polycrystalline superhard material comprising a first region and a second region, the second region being adjacent an exposed surface of the superhard structure, the second region comprising a diamond material or cubic boron nitride, the density of the second region being greater than 3.4×103 kilograms per cubic metre when the second region comprises diamond material. The material(s) forming the first and second regions have a difference in coefficient of thermal expansion, the first and second regions being arranged such that this difference induces compression in the second region adjacent the exposed surface. The first/a further region has the highest coefficient of thermal expansion of the polycrystalline body and is separated from a peripheral free surface of the body of polycrystalline superhard material by the second region or one or more further regions formed of a material or materials of a lower coefficient of thermal expansion.

Abstract: A free standing PCD body comprises a PCD material formed of combination of intergrown diamond grains forming a diamond network and an interpenetrating metallic network, the PCD body not being attached to a second body or substrate formed of a different material. The diamond network is formed of diamond grains having a plurality of grain sizes, and comprises a grain size distribution having an average diamond grain size, wherein the largest component of the diamond grain size distribution is no greater than three times the average diamond grain size. The PCD material forming the free standing PCD body is homogeneous, such that the PCD body is spatially constant and invariant with respect to diamond network to metallic network volume ratio. The homogeneity is measured at a scale greater than ten times the average grain size and spans the dimension of the PCD body. The PCD material is also macroscopically residual stress free at said scale.

Abstract: An abrasive compact comprises an ultrahard polycrystalline composite material comprised of ultrahard abrasive particles having a multimodal size distribution and a binder phase. The ultrahard polycrystalline composite material defines a plurality of interstices, the binder phase being distributed in the interstices to form greater than an optimal threshold of binder pools per square micron.

Abstract: A method of manufacturing polycrystalline abrasive elements consisting of micron, sub-micron or nano-sized ultrahard abrasives dispersed in micron, sub-micron or nano-sized matrix materials. A plurality of ultrahard abrasive particles having vitreophilic surfaces are coated with a matrix precursor material and then treated to render them suitable for sintering. The matrix precursor material can be converted to an oxide, nitride, carbide, oxynitride, oxycarbide, or carbonitride, or an elemental form thereof. The coated ultrahard abrasive particles are consolidated and sintered at a pressure and temperature at which they are crystallographically or thermodynamically stable.

Abstract: The invention relates to method of depositing refractory metal carbide onto part of a surface of a body comprising diamond, the method including adhering directly onto part of the surface a refractory precursor material comprising a compound including oxygen and at least one metal selected from the group consisting of Ti, V, Cr, Zr, Nb, Mo, Hf, Ta and W; the refractory precursor material being reducible in the presence of carbon on the application of heat to form at least one compound comprising metal carbide or mixed metal carbide; and reducing the refractory precursor material by the application of heat. The invention further relates to a body comprising diamond, part of the surface of the body having directly adhered thereto a metal carbide and part of the surface of the body having directly adhered thereto a metallic material and the content of diamond being greater than 80 volume percent of a volume of the body.

Abstract: The invention relates to a PCD composite compact element comprising a PCD structure integrally bonded at an interface to a cemented carbide substrate; the PCD structure comprising coherently bonded diamond grains having a mean size no greater than 15 microns; the cemented carbide substrate comprising carbide particles dispersed in a metallic binder, the carbide particles comprising a carbide compound of a metal; wherein the ratio of the amount of metallic binder to the amount of the metal at points in the substrate deviates from a mean value by at most 20 percent of the mean value.

Abstract: A superhard structure comprises a body of polycrystalline superhard material comprising a first region and a second region. The second region is adjacent an exposed surface of the superhard structure and comprises a diamond material or cubic boron nitride with a density greater than 3.4×103 kilograms per cubic meter when the second region comprises diamond material. The material(s) forming the first and second regions have a difference in coefficient of thermal expansion, the first and second regions being arranged such that this difference induces compression in the second region adjacent the exposed surface. The first/a further region has the highest coefficient of thermal expansion of the polycrystalline body and is separated in part from a peripheral free surface of the body by the second region or one or more further regions formed of a material(s) of a lower coefficient of thermal expansion. The regions comprise a plurality of grains of polycrystalline superhard material.

Abstract: A cutter element for rock removal comprises a free standing PCD body (801, 1801) comprising two or more physical volumes (1702, 1703) within the boundary of the PCD body, wherein adjacent physical volumes differ in one or more of diamond and metal network compositional ratio, metal elemental composition and diamond grain size distribution, a functional working volume (803) distal to the PCD body, the functional working volume forming in use a region which comes into contact with the rock. A functional support volume (804) extant in use and having a proximal free surface extends from the functional working volume. The PCD body has a shape having an aspect ratio such that the ratio of the length (ae) of the longest edge of the circumscribing rectangular parallelepiped of the overall PCD body to the largest width (ad) of the smallest rectangular face from which the functional working volume extends of the circumscribing rectangular parallelepiped, is greater than or equal to 1.

Abstract: A cutter element for rock removal comprises a free standing PCD body (801, 1801) comprising one or more physical volumes (1702, 1703), the PCD material being invariant in terms of the diamond and metal network compositional ratio and metal elemental composition such that each physical volume does not differ to any other physical volume with respect to diamond and metal network compositional ratio and metal elemental composition. The PCD body has a functional working volume (803) forming in use the region which comes into contact with the rock. A functional support volume (804) extant in use and having a proximal free surface extends from the functional working volume.