A cubic boron nitride sintered material tool contains a plurality of cBN grains. cBN grains located on a surface of the cutting edge contain a cubic boron nitride phase, and a hexagonal boron nitride phase. When a ratio I.sub.π*/I.sub.σ* between an intensity of a π* peak derived from a π bond of hBN in the hexagonal boron nitride phase and an intensity of a σ* peak derived from a σ bond of hBN in the hexagonal boron nitride phase and a σ bond of cBN in the cubic boron nitride phase is determined by measuring an energy loss associated with excitation of K-shell electrons of boron, the ratio I.sub.π*/I.sub.σ* of the cBN grain on the surface of the cutting edge is 0.1 to 2, and the ratio I.sub.π*/I.sub.σ* of the cBN grain at a depth position of 5 μm from the surface of the cutting edge is 0.001 to 0.1.

A tool main body to which an insert is attachable, in which the tool main body is made of sintered metal material, and the sintered metal material includes a parent phase made of a metal and a plurality of pores present in the parent phase.

A hob for a cutting apparatus including a hollow body of a sintered hard metal composition and a cavity located within the body, the cavity having a volume in the range of about 10% to about 90% of the volume of the body.

A sintered body of the present invention is a sintered body including a first material and cubic boron nitride. The first material is partially-stabilized ZrO.sub.2 including 5 to 90 volume % of Al.sub.2O.sub.3 dispersed in crystal grain boundaries or crystal grains of partially-stabilized ZrO.sub.2.

A base material for a hard sintered material has a multi-stage columnar shape having a central axis and extending in an axial direction of the central axis. The base material includes a smaller-diameter portion, a larger-diameter portion, a base material end surface located between a one end portion in the axial direction of an outer peripheral surface of the larger-diameter portion and the other end portion in the axial direction of the smaller-diameter portion, and facing toward the one end portion in the axial direction, and a first inclined portion disposed in at least a portion in a circumferential direction of an annular corner portion to which an outer peripheral surface of the larger-diameter portion and the base material end surface are connected. The first inclined portion is located inward in a radial direction toward the one end portion in the axial direction.

A cutting tool according to the present disclosure has a rake face, a flank face, and a cutting edge. The cutting edge is located between the rake face and the flank face. The cutting tool includes a substrate composed of a cubic boron nitride sintered material, and an oxide layer that covers the substrate and that constitutes at least part or whole of the rake face, the flank face, and the cutting edge. The oxide layer includes at least one element selected from a group consisting of titanium, aluminum, zirconium, and cobalt. A thickness of the oxide layer is 2 μm or less.

A cemented carbide cutting tool having WC and a low amount of binder phase can be used when machining Ti, Ti-alloys and Ni-based alloys under cryogenic conditions, leading to a significantly prolonged tool life.

A cutting tool body includes a first member and a second member, both having a substantially cylindrical shape, and arranged such that a tool body central axis coincides with a central axis of each of the first and the second members. The first member has a tool characteristic of a first magnitude and the second member has the tool characteristic of a second magnitude, different from the first magnitude. The cutting tool body includes a transition member arranged between the first and second members and connected at a first end to the first member and at a second end to the second member. The tool characteristic in the transition member is of the first magnitude at the first end and of the second magnitude at the second end. The transition member has a transition region between the first and the second ends in which the tool characteristic transforms from the first magnitude to the second magnitude.

A hob for a cutting apparatus including a hollow body of a sintered hard metal composition and a cavity located within the body, the cavity having a volume in the range of about 10% to about 90% of the volume of the body.

A three-dimensional shaping method including the steps, after a lamination step, in which steps of forming a powder layer, flattening with a squeegee and sintering are repeated, followed by cutting of the surface of the laminate, 1. setting the overall shape of an object to be shaped by a CAD/CAM system, and setting machining units that form the overall shape and cutting allowances on peripheral sides and upper sides of each of the machining units, 2. cutting of the peripheral sides and upper sides according to a prescribed order, after lamination with addition of a cutting allowance on the peripheral sides of each machining unit, and after carrying out lamination to the thickness of the cutting allowance on the upper side of the machining unit and the machining unit adjacent above the machining unit, and 3. continuing repetition of step 2, from the lowest to the topmost machining unit.