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 method of forming a super hard polycrystalline construction comprises forming a liquid suspension of a first mass of nano-ceramic particles and a mass of particles or grains of super hard material having an average particle or grain size of 1 or more microns, dispersing the particles or grains in the liquid suspension to form a substantially homogeneous suspension, drying the suspension to form an admix of the nano-ceramic and super hard grains or particles, and forming a pre-sinter assembly comprising the admix. The pre-sinter assembly is then sintered to form a body of polycrystalline super hard material comprising a first fraction of super hard grains and a second fraction, the nano-ceramic particles forming the second fraction.

The super hard grains are spaced along at least a portion of the peripheral surface by one or more nano-ceramic grains, the super hard grains having a greater average grain size than that of the grains in the second fraction which have an average size of less than around 999 nm.

A method of forming a super hard polycrystalline construction comprises forming a liquid suspension of nano-sized super hard particles and particles of super hard material having an average particle or grain size of 1 or more microns, dispersing the particles in the liquid suspension to form a substantially homogeneous suspension which is then dried and sintered to form a body of polycrystalline super hard material comprising a first and second fractions of super hard grains, the nano-sized particles forming the second fraction. The super hard grains in the first fraction are bonded along at least a portion of the peripheral surface(s) thereof to at least a portion of a plurality of nano-sized grains in the second fraction, the grains in the first fraction having a greater average grain size than that of the grains in the second fraction which is less than 999 nm, the average grain size of the first fraction being around 1 micron or more

A method of making a polycrystalline cubic boron nitride (PCBN), material is provided. The matrix precursor powder comprises an aluminium compound. The method comprises mixing matrix precursor powder comprising particles having an average particle size no greater than 250 nm, with between 30 and 40 volume percent of cubic boron nitride (cBN) particles having an average particle size of at least 4 μm, and then spark plasma sintering the mixed particles. The spark plasma sintering occurs at a pressure of at least 500 MPa, a temperature of no less than 1050° C. and no more than 1500° C. and a time of no less than 1 minute and no more than 3 minutes.

A polycrystalline diamond 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 comprises a plurality of alternating strata or layers, each or one or more strata or layers in the first region having a thickness in the range of around 5 to 300 microns. The polycrystalline diamond (PCD) structure has a diamond content of at most about 95 percent of the volume of the PCD material, a binder content of at least about 5 percent of the volume of the PCD material, and one or more of the layers or strata in the first region comprise and/or the second region comprises diamond grains having a mean diamond grain contiguity of greater than about 60 percent and a standard deviation of less than about 2.2 percent. There is also disclosed a method of making such a polycrystalline diamond structure.

Polycrystalline diamond may include a working surface and a peripheral surface extending around an outer periphery of the working surface. The polycrystalline diamond includes a first volume including an interstitial material and a second volume having a leached region that includes boron and titanium. A method of fabricating a polycrystalline diamond element may include positioning a first volume of diamond particles adjacent to a substrate, the first volume of diamond particles including a material that includes a group 13 element, and positioning a second volume of diamond particles adjacent to the first volume of diamond particles such that the first volume of diamond particles is disposed between the second volume of diamond particles and the substrate, the second volume of diamond particles having a lower concentration of material including the group 13 element than the first volume of diamond particles.

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

Polycrystalline diamond includes a working surface and a peripheral surface extending around an outer periphery of the working surface. The polycrystalline diamond includes a first volume including an interstitial material and a second volume having a leached region that includes boron and titanium. A method of fabricating a polycrystalline diamond element includes positioning a first volume of diamond particles adjacent to a substrate, the first volume of diamond particles including a material that includes a group 13 element, and positioning a second volume of diamond particles adjacent to the first volume of diamond particles such that the first volume of diamond particles is disposed between the second volume of diamond particles and the substrate, the second volume of diamond particles having a lower concentration of material including the group 13 element than the first volume of diamond particles. Various other articles, assemblies, and methods are also disclosed.

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 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.