A cutting tool includes a substrate and a diamond layer that covers the substrate. The diamond layer includes a rake face and a flank continuous to the rake face. A ridgeline between the rake face and the flank forms a cutting edge. The substrate includes a top surface opposed to the rake face. When viewed in a direction perpendicular to the top surface, the rake face includes a plurality of protrusions. In a cross-section perpendicular to a direction of extension of the cutting edge, each of the plurality of protrusions includes an inclined portion and a curvature portion continuous to the inclined portion. In the cross-section, a height of the inclined portion in the direction perpendicular to the top surface increases as a distance from the cutting edge increases.

A cutting tool includes a substrate and a diamond layer that covers the substrate. The diamond layer includes a rake face and a flank continuous to the rake face. A ridgeline between the rake face and the flank forms a cutting edge. The substrate includes a top surface opposed to the rake face. When viewed in a direction perpendicular to the top surface, the rake face includes a plurality of protrusions. In a cross-section perpendicular to a direction of extension of the cutting edge, each of the plurality of protrusions includes an inclined portion and a curvature portion continuous to the inclined portion. In the cross-section, a height of the inclined portion in the direction perpendicular to the top surface increases as a distance from the cutting edge increases.

A composite polycrystal contains polycrystalline diamond formed of diamond grains that are directly bonded mutually, and compressed graphite dispersed in the polycrystalline diamond.

A composite polycrystal contains polycrystalline diamond formed of diamond grains that are directly bonded mutually, and compressed graphite dispersed in the polycrystalline diamond.

A coated tool includes a base body and a diamond coating. The coated tool has a cutting edge. The first surface comprises a first region close to the cutting edge and a second region further away from the cutting edge than the first region. The diamond coating comprises an outer surface having dome-shaped protrusions. The protrusions include first protrusions having an equivalent circle diameter of 6 .Math.m or more located in the first region, and second protrusions having an equivalent circle diameter of 6 .Math.m or more located in the second region. A number of the first protrusions per 1 mm.sup.2 is a first protrusion number. A number of the second protrusions per 1 mm.sup.2 is a second protrusion number. The first protrusion number is 30 or less, and the second protrusion number is larger than the first protrusion number.

A coated tool includes a base body and a diamond coating. The coated tool has a cutting edge. The first surface comprises a first region close to the cutting edge and a second region further away from the cutting edge than the first region. The diamond coating comprises an outer surface having dome-shaped protrusions. The protrusions include first protrusions having an equivalent circle diameter of 6 .Math.m or more located in the first region, and second protrusions having an equivalent circle diameter of 6 .Math.m or more located in the second region. A number of the first protrusions per 1 mm.sup.2 is a first protrusion number. A number of the second protrusions per 1 mm.sup.2 is a second protrusion number. The first protrusion number is 30 or less, and the second protrusion number is larger than the first protrusion number.

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.

A method for manufacturing a cutting tool according to one embodiment is a method for manufacturing a cutting tool, the cutting tool including a base material and a diamond single crystal material fixed to the base material, the diamond single crystal material having a rake face, a flank face continuous with the rake face, and a cutting edge formed by a ridgeline serving as a boundary between the rake face and the flank face. The method for manufacturing a cutting tool according to one form of the present disclosure includes a flank face irradiation step of applying a laser to the diamond single crystal material along the cutting edge from a side of the flank face. The laser has a pulse width of 1×10.sup.−12 seconds or less and a peak output of less than 1 W in the flank face irradiation step.

A method for manufacturing a cutting tool according to one embodiment is a method for manufacturing a cutting tool, the cutting tool including a base material and a diamond single crystal material fixed to the base material, the diamond single crystal material having a rake face, a flank face continuous with the rake face, and a cutting edge formed by a ridgeline serving as a boundary between the rake face and the flank face. The method for manufacturing a cutting tool according to one form of the present disclosure includes a flank face irradiation step of applying a laser to the diamond single crystal material along the cutting edge from a side of the flank face. The laser has a pulse width of 1×10.sup.−12 seconds or less and a peak output of less than 1 W in the flank face irradiation step.

A single-crystal diamond having a first facet plane is prepared. The single-crystal diamond is fixed to the support based on the first facet plane. An X-ray image of the single-crystal diamond is captured, the X-ray image being an X-ray image in which a crystal orientation of the single-crystal diamond is associated with an X-ray emission direction by associating the support to which the single-crystal diamond is fixed with the X-ray emission direction. A position of an inclusion of the single-crystal diamond in the single-crystal diamond is specified based on the X-ray image. It is determined whether or not a shape of the diamond tool intermediate is extractable from the single-crystal diamond with the inclusion being not included in an inclusion-excluded region. The shape of the diamond tool intermediate is extracted from the single-crystal diamond with the inclusion being not included in the inclusion-excluded region.