A cubic boron nitride sintered material comprises 30% by volume or more and 99.9% by volume or less of cubic boron nitride grains and 0.1% by volume or more and 70% by volume or less of a binder phase, the cubic boron nitride grain having a carbon content of 0.08% by mass or less, the cubic boron nitride sintered material being free of free carbon.

A cubic boron nitride sintered material comprises 30% by volume or more and 99.9% by volume or less of cubic boron nitride grains and 0.1% by volume or more and 70% by volume or less of a binder phase, the cubic boron nitride grain having a carbon content of 0.08% by mass or less, the cubic boron nitride sintered material being free of free carbon.

An aluminum-based composite material includes a plurality of coarse crystalline grains (3) of pure aluminum, and a plurality of fine crystalline grains (4) each having an aluminum matrix (1), and a dispersion material (2) dispersed inside the aluminum matrix and formed by reacting a portion or all of an additive with aluminum in the aluminum matrix. The fine crystalline grains exist among the coarse crystalline grains, and the fine crystalline grains have crystalline grain diameters smaller than crystalline grain diameters of the coarse crystalline grains.

A composite sintered material includes: a plurality of diamond grains having an average grain size of less than or equal to 10 μm; a plurality of cubic boron nitride grains having an average grain size of less than or equal to 2 μm; and a plurality of aluminum oxide grains having an average grain size of less than or equal to 0.5 μm; and a remainder of a binder phase, wherein at least parts of adjacent diamond grains are bound to one another, the binder phase includes cobalt, in the composite sintered material, a content of the diamond grains is from 30 to 92 volume %, a content of the cubic boron nitride grains is from 3 to 40 volume %, a content of the aluminum oxide grains is from 2 to 15 volume %, and a content of the cobalt is from 3 to 30 volume %.

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.

Metal-nanoparticle composites, such as metal-boron nitride nanoparticle composites, and methods of manufacturing the same are provided. Ultrasonic casting techniques can be used to achieve uniform dispersion of nanoparticles, such as boron nitride nanotubes (BNNTs) in a metal matrix, such as aluminum. The BNNTs can be incorporated into the melt of the metal, and ultrasonic treatment can then be applied.

A drilling tip according to the disclosure has a tip body which is provided with a tip portion tapered toward a tip side of the tip body; and a hard layer which is formed on a surface of the tip portion of the tip body, an outermost layer of the hard layer is a cBN sintered material having 70 to 95 vol % of cBN grains, and when a cross-sectional structure of the outermost layer is observed, a binder phase having a width of 1 nm or greater and 30 nm or less and containing Al, B, and N, and in which a ratio of an O content to an Al content is 0.1 or less exists between neighboring cBN grains.

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 super hard polycrystalline construction includes a first region having a body of thermally stable polycrystalline super hard material with an exposed surface forming a working surface, and a peripheral side edge. The polycrystalline super hard material has a plurality of intergrown grains of super hard material, a second region forming a substrate to the first region, and a third region interposed between the first and second regions. The third region extends across a surface of the second region along an interface, the third region having a composite material having a first phase comprising a plurality of non-intergrown diamond grains, the majority of said diamond grains having a coating comprising nano-sized cBN particles. There is also disclosed a method of forming such a construction.

A super hard polycrystalline construction has a first region having a body of thermally stable polycrystalline super hard material with an exposed surface forming a working surface, and a peripheral side edge, a second region forming a substrate to the first region and a third region interposed between the first and second regions. The third region extends across a surface of the second region along an interface and has a composite material having a first phase comprising a plurality of non-intergrown diamond grains, the majority of the diamond grains having a coating comprising nano-sized BN particles. There is also disclosed a method of making such a construction.