A turning insert includes a head portion connected to a stem portion. A CBN cutting edge includes a surface generating cutting edge and two major cutting edge portions, such that each major cutting edge portion forms an angle of 5-20° in relation to a tangent line of the cutting edge at a forward point of the cutting edge.

A turning insert includes a head portion connected to a stem portion. A CBN cutting edge includes a surface generating cutting edge and two major cutting edge portions, such that each major cutting edge portion forms an angle of 5-20° in relation to a tangent line of the cutting edge at a forward point of the cutting edge.

A cutting insert and a cutting tool which can suppress lowering of blade-edge positional accuracy while holding by a holder having a small thickness is enabled are provided.

The cutting insert includes a first end surface, a second end surface, and a peripheral side surface connected to the first end surface and the second end surface and having a rake face, a flank, and a cutting edge formed in a connection region between the rake face and the flank, and a through hole penetrating the first end surface and the second end surface is formed. It is the cutting insert including a first contact surface substantially perpendicular to a center axis direction of the through hole and capable of contacting the holder, a second contact surface substantially in parallel with the center axis direction of the through hole, substantially perpendicular to a plane including the first contact surface and capable of contacting the holder, and a third contact surface inclined with respect to the center axis direction of the through hole and capable of contacting the holder, and a cutting tool including the cutting insert as above.

A cemented carbide may include a hard phase including W and C, and a binder phase including cubic Co. The binder phase may include Zr. The Co may include a lattice constant of more than 3.5575 Å and not more than 3.5600 Å. A coated tool may include a coating layer located on a surface of the cemented carbide. A cutting tool may include a holder that is extended from a first end toward a second end and may include a pocket on a side of the first end, and the coated tool located in the pocket.

A cutting head rotatable about a head axis has a cap portion and a rigid mounting protuberance joined to the cap portion. The cap portion has exactly four cutting portions circumferentially alternating with four head flutes and a head base surface facing in an axially rearward direction. The mounting protuberance extends axially rearwardly from the head base surface and has exactly two circumferentially spaced apart convex clamping surfaces. In a cross-section taken in a first horizontal plane perpendicular to the head axis and intersecting the mounting protuberance, only the two clamping surfaces are circumscribed by an imaginary first circle having a first diameter and a center coincident with the head axis. A rotary cutting tool has an elongated tool shank with a head receiving pocket at a forward end thereof and the cutting head of the type described above releasably secured to the head receiving pocket.

A cutting head rotatable about a head axis has a cap portion and a rigid mounting protuberance joined to the cap portion. The cap portion has exactly four cutting portions circumferentially alternating with four head flutes and a head base surface facing in an axially rearward direction. The mounting protuberance extends axially rearwardly from the head base surface and has exactly two circumferentially spaced apart convex clamping surfaces. In a cross-section taken in a first horizontal plane perpendicular to the head axis and intersecting the mounting protuberance, only the two clamping surfaces are circumscribed by an imaginary first circle having a first diameter and a center coincident with the head axis. A rotary cutting tool has an elongated tool shank with a head receiving pocket at a forward end thereof and the cutting head of the type described above releasably secured to the head receiving pocket.

Broaching tool comprising a cutting insert having a cutting edge and a holder for holding the cutting insert. The holder has a clamping region and a holding region, wherein the holding region comprises, at its end facing away from the clamping region, a seat for the cutting insert, which is configured and arranged such that, when the cutting insert is mounted in the seat, its cutting edge projects beyond the circumferential surface of the holding region. The holding region furthermore comprises, on its circumferential surface, a support for the cutting insert. A coolant channel extends into the inside of the holder, which coolant channel comprises two exit openings which, as seen in the circumferential direction, are arranged laterally adjacent to the support and/or in lateral surfaces of the support.

Broaching tool comprising a cutting insert having a cutting edge and a holder for holding the cutting insert. The holder has a clamping region and a holding region, wherein the holding region comprises, at its end facing away from the clamping region, a seat for the cutting insert, which is configured and arranged such that, when the cutting insert is mounted in the seat, its cutting edge projects beyond the circumferential surface of the holding region. The holding region furthermore comprises, on its circumferential surface, a support for the cutting insert. A coolant channel extends into the inside of the holder, which coolant channel comprises two exit openings which, as seen in the circumferential direction, are arranged laterally adjacent to the support and/or in lateral surfaces of the support.

A cermet, as a base, containing a plurality of hard particles and a bonded phase between the plurality of hard particles. Each of the plurality of hard particles, when viewed in cross section, includes a first region containing Ti, N, and C, and contains a titanium carbonitride phase as a main constituent. Each of the plurality of hard particles, when viewed in cross-section, includes a second region containing one or more metal elements selected from the group consisting of V, Nb, Ta, Cr, Mo, W, Co, and Ni in a larger amount than the first region. The content of the one or more metal elements in the second region is 9.5 mass % or more in a total amount. A cutting tool has a length extending from a first end to a second end, and includes a holder and the insert described above.

A turning insert includes a top surface, an opposite bottom surface, and a reference plane located parallel to and between the top and the bottom surfaces. A nose portion includes a convex nose cutting edge, and a first and a second cutting edge. The nose cutting edge connects the first and second cutting edges. The first and second cutting edges form a nose angle of 71-85° relative to each other. The nose portion has a third convex cutting edge adjacent to the first cutting edge and a fourth cutting edge adjacent to the third convex cutting edge. The fourth cutting edge forms an angle of 10-30° relative to a bisector. The distance from at least a portion of the fourth cutting edge to the reference plane increases at an increasing distance from the nose cutting edge. A second protrusion is arranged between the nose cutting edge and the first protrusion.