Abstract: A cutting tool comprising a base material and a coating disposed on the base material, wherein the coating comprises a hard particle layer; the hard particle layer is formed from a plurality of hard particles including titanium, silicon, carbon, and nitrogen; in the hard particles, a concentration of the silicon periodically changes along a first direction set in the hard particles; and an orientation of the hard particle layer is a (311) orientation.

Abstract: A cubic boron nitride sintered material comprises cubic boron nitride particles and a bonding material, wherein the bonding material comprises at least one first metallic element selected from the group consisting of titanium, zirconium, vanadium, niobium, hafnium, tantalum, chromium, rhenium, molybdenum, and tungsten; cobalt; and aluminum; the cubic boron nitride sintered material has a first interface region sandwiched between an interface between the cubic boron nitride particles and the bonding material, and a first virtual line passing through a point 10 nm apart from the interface to the bonding material side; and when an element that is present at the highest concentration among the first metallic elements in the first interface region is defined as a first element, an atomic concentration of the first element in the first interface region is higher than an atomic concentration of the first element in the bonding material excluding the first interface region.

Abstract: A cemented carbide including tungsten carbide grains and a binder phase, in which a total content of the tungsten carbide grains and the binder phase in the cemented carbide is no less than 80 vol %, a content of the binder phase in the cemented carbide is no less than 0.1 vol % and no more than 20 vol %, in a histogram showing distribution of orientation differences between adjacent pairs each consisting of two of the tungsten carbide grains adjacent to each other in the cemented carbide, a first peak is present in a class of the orientation differences of no less than 29.5° and less than 30.5°.

Abstract: A composite sintered material includes: a plurality of diamond grains having an average grain size of less than or equal to 10 ?m; a plurality of cubic boron nitride grains having an average grain size of less than or equal to 2 ?m; and a plurality of aluminum oxide grains having an average grain size of less than or equal to 0.5 ?m; 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 %.

Abstract: A cemented carbide composed of a first hard phase, a second hard phase and a binder phase, in which the first hard phase is composed of tungsten carbide particles, the second hard phase is composed of at least one first compound selected from the group consisting of TiNbC, TiNbN and TiNbCN, the second hard phase has an average particle diameter of no more than 0.1 ?m, the second hard phase has a dispersity of no more than 0.7, the second hard phase has a content of no less than 0.1 vol % and no more than 15 vol %, the binder phase contains at least one first element selected from the group consisting of iron, cobalt and nickel, and the binder phase has a content of no less than 0.1 vol % and no more than 20 vol %.

Abstract: A cubic boron nitride sintered material includes: more than or equal to 80 volume % and less than or equal to 96 volume % of cubic boron nitride grains; and a binder, wherein the binder includes tungsten carbide, cobalt, and an aluminum compound, and Ha/Hb?0.40 is satisfied, where Hb represents a hardness of the cubic boron nitride sintered material and Ha represents a hardness of the cubic boron nitride sintered material after performing acid treatment onto the cubic boron nitride sintered material to substantially remove the binder in the cubic boron nitride sintered material.

Abstract: A cutting tool includes a substrate and a coating film, wherein the coating film has a first layer formed from a plurality of hard grains, the hard grains are made of TiSiCN having a cubic crystal structure, the hard grains have a lamellar structure in which a layer having a relatively high silicon concentration and a layer having a relatively low silicon concentration are alternately stacked, and a maximum value of percentage of number ASi of silicon atoms to a sum of the number ASi of silicon atoms and number ATi of titanium atoms in a grain boundary region between the hard grains, {ASi/(ASi+ATi)}×100, is larger than an average value of percentage of number BSi of silicon atoms to a sum of the number BSi of silicon atoms and number BTi of titanium atoms in the first layer, {BSi/(BSi+BTi)}×100.

Abstract: 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.

Abstract: A cubic boron nitride sintered material comprises cubic boron nitride particles and a bonding material, wherein the bonding material comprises at least one first metallic element selected from the group consisting of titanium, zirconium, vanadium, niobium, hafnium, tantalum, chromium, rhenium, molybdenum, and tungsten; cobalt; and aluminum; the cubic boron nitride sintered material has a first interface region sandwiched between an interface between the cubic boron nitride particles and the bonding material, and a first virtual line passing through a point 10 nm apart from the interface to the bonding material side; and when an element that is present at the highest concentration among the first metallic elements in the first interface region is defined as a first element, an atomic concentration of the first element in the first interface region is higher than an atomic concentration of the first element in the bonding material excluding the first interface region.

Abstract: The cubic boron nitride sintered material is a cubic boron nitride sintered material comprising: cubic boron nitride particles in an amount of 70 vol % or more and less than 100 vol %, and a bonding material, wherein the bonding material includes an aluminum compound, and includes cobalt as a constituent element; the cubic boron nitride sintered material has a first region in which a space between adjacent cubic boron nitride particles is 0.1 nm or more and 10 nm or less; and when the first region is analyzed by using an energy dispersive X-ray analyzer equipped with a transmission electron microscope, the atom % of aluminum in the first region is 0.1 or more.

Abstract: A cemented carbide composed of a first hard phase, a second hard phase and a binder phase, in which the first hard phase is composed of tungsten carbide particles, the second hard phase is composed of at least one first compound selected from the group consisting of TiNbC, TiNbN and TiNbCN, the second hard phase has an average particle diameter of no more than 0.1 ?m, the second hard phase has a dispersity of no more than 0.7, the second hard phase has a content of no less than 0.1 vol % and no more than 15 vol %, the binder phase contains at least one first element selected from the group consisting of iron, cobalt and nickel, and the binder phase has a content of no less than 0.1 vol % and no more than 20 vol %.

Abstract: A cutting tool includes a substrate and a coating film, wherein the coating film has a first layer formed from a plurality of hard grains, the hard grains are made of TiSiCN having a cubic crystal structure, the hard grains have a lamellar structure in which a layer having a relatively high silicon concentration and a layer having a relatively low silicon concentration are alternately stacked, and a maximum value of percentage of number ASi of silicon atoms to a sum of the number ASi of silicon atoms and number ATi of titanium atoms in a grain boundary region between the hard grains, {ASi/(ASi+ATi)}×100, is larger than an average value of percentage of number BSi of silicon atoms to a sum of the number BSi of silicon atoms and number BTi of titanium atoms in the first layer, {BSi/(BSi+BTi)}×100.

Abstract: A cemented carbide including tungsten carbide grains and a binder phase, in which a total content of the tungsten carbide grains and the binder phase in the cemented carbide is no less than 80 vol %, a content of the binder phase in the cemented carbide is no less than 0.1 vol % and no more than 20 vol %, in a histogram showing distribution of orientation differences between adjacent pairs each consisting of two of the tungsten carbide grains adjacent to each other in the cemented carbide, a first peak is present in a class of the orientation differences of no less than 29.5° and less than 30.5°.

Abstract: A cubic boron nitride sintered material includes cubic boron nitride and a binder. The binder includes a first material and a second material. The first material is one or two or more first chemical species each including at least one first metallic element selected from the group consisting of tungsten, cobalt, and aluminum. Each of the first chemical species is a metal, an alloy, an intermetallic compound, a compound, or a solid solution. The second material is one or two or more second chemical species each including at least one second metallic element selected from the group consisting of titanium, zirconium, hafnium, vanadium, niobium, tantalum, and chromium. Each of the second chemical species is a solid solution derived from at least one selected from the group consisting of nitride, carbide, and carbonitride. In each of the second chemical species, 0.1 atom % to 10 atom % of aluminum is dissolved.

Abstract: The cubic boron nitride sintered material is a cubic boron nitride sintered material comprising: cubic boron nitride particles in an amount of 70 vol % or more and less than 100 vol %, and a bonding material, wherein the bonding material includes an aluminum compound, and includes cobalt as a constituent element; the cubic boron nitride sintered material has a first region in which a space between adjacent cubic boron nitride particles is 0.1 nm or more and 10 nm or less; and when the first region is analyzed by using an energy dispersive X-ray analyzer equipped with a transmission electron microscope, the atom % of aluminum in the first region is 0.1 or more.

Abstract: A composite sintered material includes a plurality of diamond grains, a plurality of cubic boron nitride grains, and a remainder of a binder phase, wherein the binder phase includes cobalt, a content of the cubic boron nitride grains in the composite sintered material is more than or equal to 3 volume % and less than or equal to 40 volume %, and an average length of line segments extending across continuous cubic boron nitride grains in appropriately specified straight lines extending through the composite sintered material is less than or equal to a length three times as large as an average grain size of the cubic boron nitride grains.

Abstract: A cubic boron nitride sintered material includes: more than or equal to 20 volume % and less than 80 volume % of cubic boron nitride grains; and more than 20 volume % and less than or equal to 80 volume % of a binder phase, and when a carbon content is measured from a cubic boron nitride grain into the binder phase in a direction perpendicular to an interface between the cubic boron nitride grain and the binder phase using TEM-EDX, a first region having a carbon content larger than an average value of a carbon content of the binder phase exists, the interface exists in the first region, and a length of the first region is more than or equal to 0.1 nm and less than or equal to 10 nm.

Abstract: A cubic boron nitride sintered material includes: more than or equal to 50 volume % and less than 80 volume % of cubic boron nitride grains; and more than 20 volume % and less than or equal to 50 volume % of a binder phase, and when an oxygen content is measured in a direction perpendicular to an interface between cubic boron nitride grains using TEM-EDX, a first region having an oxygen content larger than an average value of an oxygen content of a cubic boron nitride grain exists, the interface exists in the first region, and a length of the first region along the direction perpendicular to the interface is more than or equal to 0.1 nm and less than or equal to 10 nm.

Abstract: A cubic boron nitride sintered material includes: more than or equal to 80 volume % and less than or equal to 96 volume % of cubic boron nitride grains; and a binder, wherein the binder includes tungsten carbide, cobalt, and an aluminum compound, and Ha/Hb?0.40 is satisfied, where Hb represents a hardness of the cubic boron nitride sintered material and Ha represents a hardness of the cubic boron nitride sintered material after performing acid treatment onto the cubic boron nitride sintered material to substantially remove the binder in the cubic boron nitride sintered material.

Abstract: A cubic boron nitride sintered material includes: 20 to 80 volume % of cBN grains; and 20 to 80 volume % of a binder phase, wherein the binder phase includes first binder grains and second binder grains, in each of the first binder grains, a ratio of the number of atoms of the first metal element to a total of the number of atoms of the titanium and the number of atoms of the first metal element is more than or equal to 0.01% and less than 10%, in each of the second binder grains, this ratio is more than or equal to 10% and less than or equal to 80%, and in an X-ray diffraction spectrum of the cubic boron nitride sintered material, one or both of conditions 1 and 2 are satisfied.