Abstract: A PCD structure comprises a first region and a second region adjacent the first region, the second region being bonded to the first region by intergrowth of diamond grains; the first region comprising a plurality of alternating strata or layers, each stratum or layer having a thickness in the range of around 5 to 300 microns. The second region comprises a plurality of strata or layers, one or more strata or layers in the second region having a thickness greater than the thicknesses of the individual strata or layers in the first region. The alternating layers or strata in the first region comprise first layers or strata alternating with second layers or strata, the first layers or strata being in a state of residual compressive stress and the second layers or strata being in a state of residual tensile stress.

Abstract: A polycrystalline superhard construction comprises a body of polycrystalline superhard material, and a substrate of hard material bonded thereto along an interface. The body of polycrystalline superhard material comprises a first region abutting the substrate along the interface and a second region bonded to the first region. The second region defines a rake face, a cutting edge, a chamfer and at least a part of a flank face, the cutting edge being defined by an edge of the flank face joined to the chamfer, the chamfer extending between the cutting edge and the rake face. The height of the chamfer in a plane parallel to the plane through which the longitudinal axis of the polycrystalline superhard construction extends is less than the thickness of the second region. The first region comprises a material having coarser grains than the second region. There is also disclosed a method of making the same.

Abstract: A PCD structure comprises a first region and a second region adjacent the first region, the second region being bonded to the first region by intergrowth of diamond grains; the first region comprising a plurality of alternating strata or layers, each stratum or layer having a thickness in the range of around 5 to 300 microns. The second region comprises a plurality of strata or layers, one or more strata or layers in the second region having a thickness greater than the thicknesses of the individual strata or layers in the first region. The alternating layers or strata in the first region comprise first layers or strata alternating with second layers or strata, the first layers or strata being in a state of residual compressive stress and the second layers or strata being in a state of residual tensile stress.

Abstract: A polycrystalline superhard construction comprises a body of polycrystalline superhard material, and a substrate of hard material bonded thereto along an interface. The body of polycrystalline superhard material comprises a first region abutting the substrate along the interface and a second region bonded to the first region. The second region defines a rake face, a cutting edge, a chamfer and at least a part of a flank face, the cutting edge being defined by an edge of the flank face joined to the chamfer, the chamfer extending between the cutting edge and the rake face. The height of the chamfer in a plane parallel to the plane through which the longitudinal axis of the polycrystalline superhard construction extends is less than the thickness of the second region. The first region comprises a material having coarser grains than the second region. There is also disclosed a method of making the same.

Abstract: A tip for a degradation tool, the tip comprising a PCD structure (20) joined to a cemented carbide substrate (30); the PCD structure comprising a plurality of strata (24, 25) arranged so that adjacent strata have alternating compressive and tensile stress states, adjacent strata comprising different PCD grades and being directly bonded to each other by inter-growth of diamond grains; each stratum having a mean thickness of at most 500 microns; the PCD structure defining a working end including a rounded conical apex (22) having a radius of curvature of 1.3 mm to 4 mm.

Abstract: A pick tool for degrading asphalt or rock, comprising a PCD element; the PCD element comprising a PCD structure (20) bonded to a cemented carbide support body (30) at an interface; the PCD structure comprising a first region (24) and a second region (25) adjacent the first region, the second region bonded to the first region by intergrowth of diamond grains; the first region (24) comprising a plurality of alternating strata (24c, 24t), each stratum having a thickness in the range of about 30 to 300 microns; the second region comprising a plurality of strata (25a, 25b), one or more strata in the second region (25a) having a thickness greater than the thicknesses of the individual strata in the first region (24c, 24t), wherein the alternating strata in the first region (24) comprise first strata alternating with second strata, the first strata being in a state of residual compressive stress and the second strata being in a state of residual tensile stress.

Abstract: A tip for a degradation tool, the tip comprising a PCD structure (20) joined to a cemented carbide substrate (30); the PCD structure comprising a plurality of strata (24, 25) arranged so that adjacent strata have alternating compressive and tensile stress states, adjacent strata comprising different PCD grades and being directly bonded to each other by inter-growth of diamond grains; each stratum having a mean thickness of at most 500 microns; the PCD structure defining a working end including a rounded conical apex (22) having a radius of curvature of 1.3 mm to 4 mm.

Abstract: A PCD structure comprises a first region (24) and a second region (25) adjacent the first region, the second region being bonded to the first region by intergrowth of diamond grains; the first region comprising a plurality of alternating strata or layers (24c, 24t), each stratum or layer having a thickness in the range of around 5 to 300 microns. The second region (25) comprises a plurality of strata or layers, one or more strata or layers in the second region having a thickness greater than the thicknesses of the individual strata or layers in the first region (24). The alternating layers or strata in the first region comprise first layers or strata alternating with second layers or strata, the first layers or strata being in a state of residual compressive stress and the second layers or strata being in a state of residual tensile stress.

Abstract: A pick tool for degrading asphalt or rock, comprising a PCD element; the PCD element comprising a PCD structure (20) bonded to a cemented carbide support body (30) at an interface; the PCD structure comprising a first region (24) and a second region (25) adjacent the first region, the second region bonded to the first region by intergrowth of diamond grains; the first region (24) comprising a plurality of alternating strata (24c, 24t), each stratum having a thickness in the range of about 30 to 300 microns; the second region comprising a plurality of strata (25a, 25b), one or more strata in the second region (25a) having a thickness greater than the thicknesses of the individual strata in the first region (24c, 24t), wherein the alternating strata in the first region (24) comprise first strata alternating with second strata, the first strata being in a state of residual compressive stress and the second strata being in a state of residual tensile stress.

Abstract: A polycrystalline diamond (PCD) material 10 comprising at least 88 volume percent and at most 99 volume percent diamond grains 12, the mean diamond grain contiguity being greater than 60.5 percent. The PCD material 10 is particularly but not exclusively for use in boring into the earth.

Abstract: A polycrystalline diamond (PCD) material 10 comprising at least 88 volume percent and at most 99 volume percent diamond grains 12, the mean diamond grain contiguity being greater than 60.5 percent. The PCD material 10 is particularly but not exclusively for use in boring into the earth.

Abstract: A polycrystalline superhard construction comprises a body of polycrystalline superhard material, and a substrate of hard material bonded thereto along an interface. The body of polycrystalline superhard material comprises a first region abutting the substrate along the interface and a second region bonded to the first region. The second region defines a rake face, a cutting edge, a chamfer and at least a part of a flank face, the cutting edge being defined by an edge of the flank face joined to the chamfer, the chamfer extending between the cutting edge and the rake face. The height of the chamfer in a plane parallel to the plane through which the longitudinal axis of the polycrystalline superhard construction extends is less than the thickness of the second region. The first region comprises a material having coarser grains than the second region. There is also disclosed a method of making the same.

Abstract: A method of producing a boron suboxide composite material having improved fracture toughness.

Abstract: A boron suboxide composite material having improved fracture toughness consists of particulate or granular boron suboxide distributed in a binder phase, such as AlxByOz, for example.

Abstract: A boron suboxide composite material having improved fracture toughness consists of particulate or granular boron suboxide distributed in a binder phrase, such as AlxByOz, for example.

Abstract: A polycrystalline diamond (PCD) material 10 comprising at least 88 volume percent and at most 99 volume percent diamond grains 12, the mean diamond grain contiguity being greater than 60.5 percent. The PCD material 10 is particularly but not exclusively for use in boring into the earth.

Abstract: The invention is for an ultrahard composite material comprising a diamond phase and a binder phase, the binder phase comprising a ternary carbide of the general formula Mx M?y C wherein; M is at least one metal selected from the group consisting of the transition metals and the rare earth metals, M? is a metal selected from the group consisting of the main group metals or metalloid elements and the transition metals Zn and Cd, x is from 2.5 to 5.0, y is from 0.5 to 3.0 and z is from 0.1 to 1. The invention extends to a diamond abrasive compact comprising such an ultrahard composite material and to a tool comprising such a diamond abrasive compact.

Abstract: A boron suboxide composite material having improved fracture toughness consists of particulate or granular boron suboxide distributed in a binder phrase, such as AlxByOz, for example.