Abstract: It is an object of the present invention to provide a sintered cBN compact having excellent wear resistance and fracture resistance even in machining centrifugally cast iron having a property of being difficult to machine, and to provide a sintered cBN compact tool. A sintered cBN compact of the present invention contains 20% by volume or more and 65% by volume or less of cBN and, as a binder, 34% by volume or more and less than 80% by volume of Al2O3, at least one selected from the group consisting of nitrides, carbides, carbonitrides, borides, and boronitrides of Zr and solid solutions thereof (hereinafter, referred to as “X”), and ZrO2, the total amount of X and ZrO2 being 1.0% by volume or more and 6.0% by volume or less, the volume ratio of ZrO2 to Al2O3, ZrO2/Al2O3, being 0.010 or more and less than 0.100, in which the ratio Itetragonal ZrO2(101)/I?Al2O3(110) is 0.

Abstract: A cutting tool including a cutting insert for which corner changing can be performed, the cutting tool having a large number of usable corners and thereby being cost effective, reducing cutting force during machining, and ensuring high rigidity. A negative-type cutting insert having a regular polygonal shape with five to eight corners is attached to an end of a tool holder such that one of two adjacent sides of an outer peripheral surface serves as a rake face having a negative rake angle, the other of the two adjacent sides serves as a front flank face, a ridge between the two adjacent sides of the outer peripheral surface serves as an end cutting edge, and a ridge between the side that serves as the rake face and one of top and bottom surfaces serves as a side cutting edge, and such that corner changing can be performed.

Abstract: A composite sintered body according to the present invention contains at least cubic boron nitride and a binder. Cubic boron nitride has a continuous skeleton structure as a result of bonding of a plurality of first cubic boron nitride particles to each other. The binder has a continuous structure as a result of bonding of a plurality of binder particles to each other, that are present in a region except for a bonding interface where the first cubic boron nitride particles are bonded to each other. Second cubic boron nitride particles isolated from the first cubic boron nitride particles forming the skeleton structure are dispersed in the continuous structure of the binder particles.

Abstract: A tool includes, at least on its edge, a sintered cBN compact which includes cBN particles and a bonding phase, a plurality of flutes is formed on a rake face, each of the flutes having a starting end on the edge ridgeline and causing the edge ridgeline to be wavy, and the terminal end of the flute is disposed inwardly of the edge ridgeline. It is preferable that the flute width of the flute decreases with distance from the edge ridgeline, the flute depth of the flute decreases with distance from the edge ridgeline, and the rake face has a positive rake angle.

Abstract: There is provided a surface-coated sintered body formed of a sintered body of cubic boron nitride with a sufficiently adhesive surface coating layer thereon. The present surface-coated sintered body includes a sintered body of cubic boron nitride and a surface coating layer formed on a surface thereof, the sintered body of cubic boron nitride including 20-99.5% by volume of cubic boron nitride and a binder, the surface coating layer including an adhesion layer and at least one hard coating layer, the adhesion layer being a metal layer including at least W, and being formed to cover a surface of the sintered body of cubic boron nitride, the hard coating layer being formed to coat the adhesion layer, the adhesion layer being configured of an amorphous state and/or ultrafine particles having an average particle size equal to or smaller than 5 nm.

Abstract: The cubic boron nitride sintered body tool of the present invention has a cubic boron nitride sintered body including cubic boron nitride particles and a binder phase at at least a cutting edge. The cubic boron nitride sintered body includes 40-70 volume % of cubic boron nitride particles. The binder phase includes a first component and a second component. The first component includes TiC, and the second component includes one or both of TiB2 and AlB2. When the X-ray diffraction intensity of plane (200) of the first component is I1 and the X-ray diffraction intensity of plane (101) of said second component is I2, I1 is the maximum of the X-ray diffraction intensity of all components in the cubic boron nitride sintered body excluding the cubic boron nitride particles, and satisfies 0.01?I2/I1?0.1.

Abstract: A tool includes a cubic boron nitride sintered body at least at a tool working point. The cubic boron nitride sintered body contains cubic boron nitride, a heat insulating phase, and a binder phase. Cubic boron nitride is contained in the cubic boron nitride sintered body by not less than 60 volume % and not more than 99 volume %, and the heat insulating phase includes one or more types of first compound composed of one or more types of element selected from the group consisting of Al, Si, Ti, and Zr and one or more types of element selected from the group consisting of N, C, O, and B. The first compound is contained in the cubic boron nitride sintered body by not less than 1 mass % and not more than 20 mass % and it has an average particle size smaller than 100 nm.

Abstract: The present joined product is a joined product with a cemented carbide sintered compact serving as a first material to be joined and a cBN sintered compact serving as a second material to be joined, wherein: the first material to be joined and the second material to be joined are joined together via a joining material disposed therebetween and containing titanium (Ti); and a titanium nitride (TiN) compound layer having a thickness of 10-300 nm is produced at an interface between the second material to be joined and the joining material.

Abstract: A surface-coated sintered body includes a sintered body of cubic boron nitride (cBN) and a surface coating layer formed on a surface thereof, the sintered body of cBN containing 20 to 99.5% by volume of cBN and a binder, the surface coating layer including an adhesion layer and at least one hard coating layer, the adhesion layer being a metal layer containing at least W and being formed to cover a portion of the surface of the sintered body of cBN, the hard coating layer being formed to cover the sintered body of cBN and the adhesion layer, a ratio of cBN particles in contact with the adhesion layer to a total number of cBN particles in contact with the adhesion layer or the hard coating layer in the surface of the sintered body of cBN being 0.01 to 20%.

Abstract: It is an object of the present invention to provide a sintered cBN compact having excellent wear resistance and fracture resistance even in machining centrifugally cast iron having a property of being difficult to machine, and to provide a sintered cBN compact tool. A sintered cBN compact of the present invention contains 20% by volume or more and 65% by volume or less of cBN and, as a binder, 34% by volume or more and less than 80% by volume of Al2O3, at least one selected from the group consisting of nitrides, carbides, carbonitrides, borides, and boronitrides of Zr and solid solutions thereof (hereinafter, referred to as “X”), and ZrO2, the total amount of X and ZrO2 being 1.0% by volume or more and 6.0% by volume or less, the volume ratio of ZrO2 to Al2O3, ZrO2/Al2O3, being 0.010 or more and less than 0.100, in which the ratio Itetragonal ZrO2(101)/I?Al2O3(110) is 0.

Abstract: A tool made of a cubic boron nitride sintered body which has a long life in a stable manner in any application of cutting and plastic working is provided. The tool made of the cubic boron nitride sintered body according to the present invention includes a cubic boron nitride sintered body at least at a tool working point and it is characterized by satisfying an Equation (I) and any one of an Equation (II) and an Equation (III) 20?X?98??(I) Y?0.6×X+3 (where 20?X<88)??(II) Y?5.8×X?455 (where 88?X?98)??(III) where a ratio of cubic boron nitride contained in the cubic boron nitride sintered body is denoted as X volume % and thermal conductivity of the cubic boron nitride sintered body is denoted as Y (W/m·K).

Abstract: The cubic boron nitride sintered body tool of the present invention has a cubic boron nitride sintered body including cubic boron nitride particles and a binder phase at at least a cutting edge. The cubic boron nitride sintered body includes 40-70 volume % of cubic boron nitride particles. The binder phase includes a first component and a second component. The first component includes TiC, and the second component includes one or both of TiB2 and AlB2. When the X-ray diffraction intensity of plane (200) of the first component is I1 and the X-ray diffraction intensity of plane (101) of said second component is I2, I1 is the maximum of the X-ray diffraction intensity of all components in the cubic boron nitride sintered body excluding the cubic boron nitride particles, and satisfies 0.01?I2/I1?0.1.

Abstract: There is provided a surface-coated sintered body formed of a sintered body of cubic boron nitride with a sufficiently adhesive surface coating layer thereon. The present surface-coated sintered body includes a sintered body of cubic boron nitride and a surface coating layer formed on a surface thereof, the sintered body of cubic boron nitride including 20-99.5% by volume of cubic boron nitride and a binder, the surface coating layer including an adhesion layer and at least one hard coating layer, the adhesion layer being a metal layer including at least W, and being formed to cover a surface of the sintered body of cubic boron nitride, the hard coating layer being formed to coat the adhesion layer, the adhesion layer being configured of an amorphous state and/or ultrafine particles having an average particle size equal to or smaller than 5 nm.

Abstract: cBN sintered body includes cBN and a binder phase, wherein a content of the cBN is 82-98 volume %, and in a cross section of the cBN sintered body, an isolated binder phase having an area of 0.05-0.5 ?m2 has a protrusion of two or more steps, and assuming that in a first-step protrusion, A1 represents a side length which is perpendicular in a tip direction, and B1 represents a side length which is parallel in the tip direction; and in a second-step protrusion, A2 represents a side length which is perpendicular in the tip direction, and B2 represents a side length which is parallel in the tip direction, an area ratio of an isolated binder phase having a protrusion in which A1/B1 is 1-10 times of A2/B2, to the whole of the binder phase having the area of 0.05-0.5 ?m2, is 25% or more.

Abstract: In a pilot hole of a workpiece made of a difficult-to-cut cast iron, a cutting tool having a leading end to which a cutting insert is attached is inserted to cut the surface of the wall of the pilot hole. At this time, the cutting tool rotates about an axis (?) and also revolves about another axis (?), so that contouring is performed on the workpiece by the tool. The cutting insert is formed of a sintered body having a CBN content of not less than 85% by volume, and the cutting insert has a thermal conductivity of not less than 100 W/(mK).

Abstract: A cubic boron nitride sintered body tool has, at least at a cutting edge, a cubic boron nitride sintered body composed of a cubic boron nitride particle and a binder phase. The binder phase contains at least Al2O3 and a Zr compound. On any straight line in the sintered body, the mean value of a continuous distance occupied by Al2O3 is 0.1-1.0 ?m, and the standard deviation of the continuous distance occupied by Al2O3 is not more than 0.8. On the straight line, X/Y is 0.1-1 where X represents the number of points of contact between Al2O3 and the Zr compound, and Y represents the sum of the number of points of contact between Al2O3 and cBN and the number of points of contact between Al2O3 and binder phase component(s) other than Al2O3 and the Zr compound.

Abstract: A surface-covered CBN sintered body tool includes a base material formed with a cubic boron nitride (CBN) sintered body and a surface covering film covering a surface of the base material, and has a nega-land exposing the CBN sintered body in at least a portion thereof and a flank having the surface covering film formed thereon. With this, the surface-covered CBN sintered body tool having high defect resistance and wear resistance can be provided. The surface covering film preferably includes a nitride or a carbonitride of a compound including at least one element selected from the group consisting of Ti, Cr, Zr, and V and at least one element selected from the group consisting of Al, Si and B, or a nitride or a carbonitride of Ti.

Abstract: The composite sintered body of the invention is a composite sintered body, containing 20 volume % or more and 80 volume % or less of cubic boron nitride particles, and a binder; wherein the binder contains at least one selected from the group consisting of nitrides, carbides, borides, and oxides of elements in the group 4a, elements in the group 5a, and elements in the group 6a in the periodic table, and solid solutions thereof, at least one selected from the group consisting of simple substances of Zr, Si, Hf, Ge, W and Co, compounds thereof, and solid solutions thereof, and a compound of Al; and when the composite sintered body contains therein W and/or Co, the total weight of the W and/or Co is less than 2.0 weight % and further the composite sintered body contains therein one or more of the Zr, Si, Hf and Ge (hereinafter referred to as “X”), and when the composite sintered body contains the X, the amount of each of the X is 0.005 weight % or more and less than 2.0 weight %, X/(X+W+Co) is 0.

Abstract: A surface-covered CBN sintered body tool includes a base material formed with a cubic boron nitride (CBN) sintered body and a surface covering film covering a surface of the base material, and has a nega-land exposing the CBN sintered body in at least a portion thereof and a flank having the surface covering film formed thereon. With this, the surface-covered CBN sintered body tool having high defect resistance and wear resistance can be provided. The surface covering film preferably includes a nitride or a carbonitride of a compound including at least one element selected from the group consisting of Ti, Cr, Zr, and V and at least one element selected from the group consisting of Al, Si and B, or a nitride or a carbonitride of Ti.