Abstract: A cutting tool includes a substrate and a hard layer, wherein the hard layer includes a first unit layer and a second unit layer being alternately layered in the hard layer, a thickness of the first unit layer is 2 to 100 nm, a thickness of the second unit layer is 2 to 100 nm, the first unit layer is composed of TiaAlbBcN, the second unit layer is composed TidAleBfN, an atomic ratio a satisfy 0.25?a<0.45, an atomic ratio b satisfy 0.55?b<0.75, an atomic ratio c satisfy 0<c?0.1, a total of the atomic ratios a, b and c is 1, an atomic ratio d satisfy 0.35?d<0.55, an atomic ratio e satisfy 0.45?e<0.65, an atomic ratio f satisfy 0<f?0.1, a total of the atomic ratios d, e and f is 1, the atomic ratios a and d satisfy 0.05?d?a?0.2, and the atomic ratios b and e satisfy 0.05?b?e?0.2.

Abstract: A cutting tool including a base material and a hard layer provided on the base material, in which the hard layer is composed of a compound represented by TiaAlbBcN, an atomic ratio a is 0.25 or more and less than 0.55, an atomic ratio b of is 0.45 or more and less than 0.75, an atomic ratio c of is more than 0 and 0.1 or less, a sum of the atomic ratio a, the atomic ratio b and the atomic ratio c is 1, a ratio I(200)/I(002) of an intensity I(200) of an X-ray diffraction peak of a (200) plane to an intensity I(002) of an X-ray diffraction peak of a (002) plane in the hard layer is 2 to 10, and a full width at half maximum of the X-ray diffraction peak of the (002) plane is 2 degrees to 8 degrees.

Abstract: A cemented carbide includes first hard phase grains, second hard phase grains, third hard phase grains, and a metal binder phase, wherein the cemented carbide has a total of 70 unit regions, the number of unit regions each having a percentage of less than 0.43% or more than 2.43% is ?10 among the total of 70 unit regions, the percentage being a percentage of the total number of the second and the third hard phase grains in each unit region with respect to the total number of the second and the third hard phase grains in the total of 70 unit regions, and in a total of 10 unit regions existing in a fourth row in a longitudinal direction, a percentage of the number of the third hard phase grains with respect to the total number of the second and the third hard phase grains is 5% to 15%.

Abstract: Cemented carbide contains first hard-phase particles containing WC, second hard-phase particles which contain carbonitride containing at least Ti and Nb, and a metallic binder phase containing an iron-group element. The second hard-phase particle includes a granular core portion. The core portion contains composite carbonitride expressed as Ti1-X-YNbXWYC1-ZNZ, where X is not smaller than 0.1 and not greater than 0.2, Y is not smaller than 0 and not greater than 0.05, and Z is not smaller than 0.3 and not greater than 0.6. The cemented carbide has an absolute value of a difference not greater than 10, between a ratio (%) of an area occupied by the second hard-phase particles at a surface thereof and a ratio (%) of an area occupied by the second hard-phase particles in a region extending from the surface by 0.5 mm in a direction of depth.

Abstract: A cemented carbide includes first hard phase grains, second hard phase grains, third hard phase grains, and a metal binder phase, wherein the cemented carbide has a total of 70 unit regions, the number of unit regions each having a percentage of less than 0.43% or more than 2.43% is ?10 among the total of 70 unit regions, the percentage being a percentage of the total number of the second and the third hard phase grains in each unit region with respect to the total number of the second and the third hard phase grains in the total of 70 unit regions, and in a total of 10 unit regions existing in a fourth row in a longitudinal direction, a percentage of the number of the third hard phase grains with respect to the total number of the second and the third hard phase grains is 5% to 15%.

Abstract: A titanium carbonitride powder for use as a starting material for a hard material satisfies a D50 of from 2.0 ?m to 6.0 ?m and a D10/D90 of from 0.20 to 0.50, wherein D50 is a particle size at a cumulative percentage of 50% of a particle size distribution by volume, D10 is a particle size at a cumulative percentage of 10% of the particle size distribution by volume, and D90 is a particle size at a cumulative percentage of 90% of the particle size distribution by volume.

Abstract: A hard material includes a first hard phase containing titanium carbonitride as a major constituent and a binder phase containing an iron group element as a major constituent. In any surface or cross-section of the hard material, the grain size D50 at a cumulative percentage of 50% of a grain size distribution by area of the first hard phase is 1.0 ?m or more, and the average aspect ratio of first hard phase particles having grain sizes larger than or equal to D50 is 2.0 or less.

Abstract: A cemented carbide includes second hard phase grains, wherein the second hard phase grains includes a core portion, and in a case where a total of 70 unit regions that are each constituted of a square having each side of 8?m are provided by successively arranging 7 unit regions in a longitudinal direction and 10 unit regions in a lateral direction in an electron microscope image of any cross section of the cemented carbide captured at a magnification of 1500×, where the total number of core portions in the total of 70 unit regions is calculated, and where a percentage of the number of core portions in each of the unit regions with respect to the total number of core portions is calculated, the number of unit regions in which the percentage is less than 0.43% or more than 2.43% is less than or equal to 10.

Abstract: Cemented carbide contains first hard-phase particles containing WC, second hard-phase particles which contain carbonitride containing at least Ti and Nb, and a metallic binder phase containing an iron-group element. The second hard-phase particle includes a granular core portion and a peripheral portion which covers at least a part of the core portion. The core portion contains composite carbonitride expressed as Ti1-X-YNbXWYC1-ZNZ, where Y is not smaller than 0 and not greater than 0.05 and Z is not smaller than 0.3 and not greater than 0.6. The peripheral portion is different in composition from the core portion.

Abstract: A titanium carbonitride powder for use as a starting material for a hard material satisfies a D50 of from 2.0 ?m to 6.0 ?m and a D10/D90 of from 0.20 to 0.50, wherein D50 is a particle size at a cumulative percentage of 50% of a particle size distribution by volume, D10 is a particle size at a cumulative percentage of 10% of the particle size distribution by volume, and D90 is a particle size at a cumulative percentage of 90% of the particle size distribution by volume.

Abstract: Cemented carbide contains first hard-phase particles containing WC, second hard-phase particles which contain carbonitride containing at least Ti and Nb, and a metallic binder phase containing an iron-group element. The second hard-phase particle includes a granular core portion. The core portion contains composite carbonitride expressed as Ti1?X?YNbXWYC1?ZNZ, where X is not smaller than 0.1 and not greater than 0.2, Y is not smaller than 0 and not greater than 0.05, and Z is not smaller than 0.3 and not greater than 0.6. The cemented carbide has an absolute value of a difference not greater than 10, between a ratio (%) of an area occupied by the second hard-phase particles at a surface thereof and a ratio (%) of an area occupied by the second hard-phase particles in a region extending from the surface by 0.5 mm in a direction of depth.

Abstract: A hard material includes a first hard phase containing titanium carbonitride as a major constituent and a binder phase containing an iron group element as a major constituent. In any surface or cross-section of the hard material, the grain size D50 at a cumulative percentage of 50% of a grain size distribution by area of the first hard phase is 1.0 ?m or more, and the average aspect ratio of first hard phase particles having grain sizes larger than or equal to D50 is 2.0 or less.

Abstract: A cemented carbide includes second hard phase grains, wherein the second hard phase grains includes a core portion, and in a case where a total of 70 unit regions that are each constituted of a square having each side of 8?m are provided by successively arranging 7 unit regions in a longitudinal direction and 10 unit regions in a lateral direction in an electron microscope image of any cross section of the cemented carbide captured at a magnification of 1500×, where the total number of core portions in the total of 70 unit regions is calculated, and where a percentage of the number of core portions in each of the unit regions with respect to the total number of core portions is calculated, the number of unit regions in which the percentage is less than 0.43% or more than 2.43% is less than or equal to 10.

Abstract: Cemented carbide contains first hard-phase particles containing WC, second hard-phase particles which contain carbonitride containing at least Ti and Nb, and a metallic binder phase containing an iron-group element. The second hard-phase particle includes a granular core portion and a peripheral portion which covers at least a part of the core portion. The core portion contains composite carbonitride expressed as Ti1-X-YNbXWYC1-ZNZ, where Y is not smaller than 0 and not greater than 0.05 and Z is not smaller than 0.3 and not greater than 0.6. The peripheral portion is different in composition from the core portion.