Abstract: A cutting insert of the present invention comprises: an upper surface and a lower surface; first and second lateral surfaces; first and second cutting edge parts; and corner cutting edges, wherein the first cutting edge part includes: a first main cutting edge for forming one end at a portion spaced farthest away from the corner cutting edge; a first sub-cutting edge connected to the corner cutting edge; and a first auxiliary cutting edge for connecting the first main cutting edge and the first sub-cutting edge so as to form a step between the same, and the first sub-cutting edge and the corner cutting edge form one straight line when viewed toward the first lateral surface, and are inclined upward in the direction opposite to the direction toward the lower surface while gradually going in the direction toward the second cutting edge part.

Abstract: A cutting insert for groove machining is provided, which includes a front cutting edge, a chip breaker groove extending from a rear direction of the front cutting edge in a lengthwise direction of the cutting insert, land portions formed on both sides of the chip breaker groove, and inclined surfaces in continuity with the land portions and extending from the land portions to a rear direction of the cutting insert, in which a distance in a transverse direction between left and right walls of the chip breaker groove gradually increases from an entrance of the chip breaker groove toward a boundary between the land portions and the inclined surfaces, and then gradually decreases upon passing the boundary, and the cutting insert is symmetrical about a longitudinal center line thereof.

Abstract: The present disclosure relates to a cutting insert, and a cutting insert according to the present disclosure comprises: an upper surface and a lower surface oriented in opposite directions; a first and a second shorter side surface connecting the upper surface and the lower surface to each other and oriented in opposite directions; a first and a second longer side surfaces connecting the upper surface and the lower surface to each other, connecting the first and the second shorter side surfaces to each other, oriented in opposite directions, and being longer than the first and the second shorter side surfaces; and a through hole extending through the upper surface and the lower surface, wherein when viewed toward the upper surface, the first longer side surface has two side portions, each side portion having an inclined shape with reference to the center portion.

Abstract: A hard coating includes a thin film layer which has a total thickness of 0.5-10 ?m and has an overall composition of Al1-a-bTiaMebN (0.2<a?0.6, 0<b?0.15), where Me is a nitride constituent element having a thermal expansion coefficient of greater than 2.7×10?6/° C. and less than 9.35×10?6/° C., wherein the thin film layer has a structure in which a nano-multilayered-structure of thin layers A, B and C, thin layer B being disposed between thin layer A and thin layer C, is repeatedly laminated at least once.

Abstract: The present invention relates to a hard coating including an MT-TiCN layer and an ?-alumina layer which are formed by using a chemical vapor deposition method. A hard coating for cutting tools, which is a coating formed on a base material of a cutting tool formed of a hard material, the coating comprising: a TiCN layer; and an ?-alumina layer formed on the TiCN layer, wherein: the ?-alumina layer has a main peak (maximal strength peak) of (006) plane located between 20-40 degrees during a psi rocking analysis by an XRD; a residual stress in the ?-Al2O3 layer is ?0.9-0.4 GPa; the TiCN layer is composed of TiCxNyOz (x+y+z?1, x>0, y>0, z?0); a composition ratio of C/(C+N) is greater than or equal to 0.4 and smaller than 0.5; the ratio of TC(220)/TC(422) is smaller than 0.45; and the ratio of TC(220)/TC(311) is less than 0.45.

Abstract: The technical objective of the present invention is to provide a cutting insert cooling device capable of easily mounting a spraying member to a cutting tool while preventing the rotation thereof and eliminating the risk of losing a screw. To this end, the cutting insert cooling device according to the present invention, capable of spraying cooling water toward the cutting insert coupled to the cutting tool, comprises: a head part which forms the terminal end portion of the cutting tool and has a cooling water guide flow path part, and to which the cutting insert is coupled; a spraying member having a cooling water spouting flow path part to spray, toward the cutting insert, the cooling water guided through the cooling water guide flow path part; and an attaching and detaching unit that slides the spraying member to the head part so as to attach and detach the same.

Abstract: The present disclosure relates to a cutting insert. The cutting insert according to the exemplary embodiment of the present disclosure has a dot formed between a main cutting edge and a chip breaker, and the dot has a bridge formed between the main cutting edges. Therefore, a chip, which is produced during a cutting process, may come into contact with three points on a main cutting edge land portion, the bridge, and the dot. The chip may discharge heat generated from the cutting insert while the chip comes into contact with the three points.

Abstract: The technical objective of the present invention is to provide a cutting insert that has an improved fastening property with a cutting tool, thereby preventing reduction of the service life. To this end, the cutting insert according to the present invention has three corners along the circumference thereof; an upper main cutting edge, which is formed on the edge between the upper surface and the first side surface, and an upper sub cutting edge, which is formed on the edge between the upper surface and the second side surface, are continuously disposed between respective corners; the lower surface has the same shape as that of the upper surface; and the angle defined between the upper main cutting edge and the upper sub cutting edge, which are placed on both sides with reference to each corner, is larger than or equal to 85° and is smaller than 90°.

Abstract: The technical objective of the present invention is to provide a cutting insert that can minimize a phenomenon in which the cutting insert is lifted up from a seat surface of a cutting tool while a cutting process is being performed, and can increase an area by which the cutting insert is fastened to the cutting tool.

Abstract: A cutting insert and a cutting tool having same. The cutting insert includes: an upper surface; a lower surface having a flat surface; a fastening hole penetrating the upper surface and the lower surface; side surfaces each connecting to the upper surface and the lower surface; and cutting edges formed by the upper surface and the side surfaces. A first cutting edge is inclined downward. A major side surface comprises a first major side surface connected to the upper surface so as to constitute the first cutting edge, and a second major side surface connected to the first major side surface and the lower surface. A minor side surface comprises a first minor side surface connected to the upper surface so as to constitute a second cutting edge, and a third minor side surface connected to the upper surface and the lower surface.

Abstract: Provided are a cutting insert and a tool holder on which the cutting insert is provided. The cutting insert includes a circular upper surface, a circular lower surface, a cylindrical lateral surface for connecting the upper surface and the lower surface, an upper cutting edge formed between the upper surface and the lateral surface, a lower cutting edge formed between the lower surface and the lateral surface, and a plurality of rotation-preventing parts provided at the lateral surface so as to prevent the cutting insert from rotating with respect to the tool holder. Each rotation preventing part includes an inner curved surface recessed toward the center of the lateral surface and convexly rounded so as to form concentric circles in conjunction with the lateral surface, and a stepped rotation-preventing surface parallel to the axial direction of the insert and connecting the inner curved surface and the lateral surface.

Abstract: A cutting insert for an indexable drill according to the present disclosure may be used for external cutting or internal cutting depending on a position and a direction in which the cutting insert is installed even though a single type of cutting insert is provided. In addition, the cutting insert for an indexable drill according to the present disclosure has a section of the internal cutting edge which is involved in a cutting process or a section of the internal cutting edge which is not involved in the cutting process, which are clearly distinguished from each other, and as a result, the cutting insert may be rotated and mounted, and reversed and mounted on a drill body, such that maximum eight corners may be used to perform a cutting process.

Abstract: The technical objective of the present invention is to provide a cutting insert that can minimize a phenomenon in which the cutting insert is lifted up from a seat surface of a cutting tool while a cutting process is being performed, and can increase an area by which the cutting insert is fastened to the cutting tool.

Abstract: The present disclosure relates to a cutting insert. The cutting insert according to the exemplary embodiment of the present disclosure has a dot formed between a main cutting edge and a chip breaker, and the dot has a bridge formed between the main cutting edges. Therefore, a chip, which is produced during a cutting process, may come into contact with three points on a main cutting edge land portion, the bridge, and the dot. The chip may discharge heat generated from the cutting insert while the chip comes into contact with the three points.

Abstract: Provided is an insert for being mounted on a tool holder. The insert includes three substantially right-angled corners along a perimeter, a main cutting edge, a sub cutting edge, and a flat lower surface. A clearance angle of a second end main side surface forms an obtuse angle with respect to a lower surface, and a clearance angle of a second end sub side surface forms an obtuse angle with respect to the lower surface. A clearance angle of a first end main side surface forms a right angle with respect to the lower surface, and a clearance angle of a first end sub side surface forms a right angle with respect to the lower surface.