A cutting insert according to an aspect includes a base portion and a cutting portion. The cutting portion includes a front end surface, an top surface, a first lateral surface, a second lateral surface, a front cutting edge, and a lateral cutting edge. The front cutting edge includes a first cutting edge and a second cutting edge, and a radius of curvature of the first cutting edge is greater than a radius of curvature of the second cutting edge.

A cutting tool includes a two-way indexable cutting insert clamped in a transversely oriented insert receiving pocket of an insert holder. The insert holder includes a forwardly located insert mounting portion that includes upper and lower jaws which together define the insert receiving pocket having a pocket front opening. The lower jaw includes a pocket lower clamping surface. The upper jaw includes a pocket upper clamping surface which faces mutually towards the pocket lower clamping surface and a pocket stopper surface facing generally towards the pocket front opening. The pocket stopper surface is closer to the pocket lower clamping surface and further from the pocket front opening, than the pocket upper clamping surface. The pocket stopper surface is further from the pocket rear opening than the pocket lower clamping surface.

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 cutting insert, for producing a V-shaped profile in a workpiece by radial piercing relative to an axis of rotation of the workpiece, includes a reference plane and a V-shaped insertion region. The V-shaped insertion region includes, inter alia, two cutting edges in the reference plane, a rake face and a plurality of elongated chip-guiding depressions in the rake face, each extending in parallel with a depression axis of extent or extension axis in the reference plane, providing improved chip formation compared to the prior art. The depression axes of extent or extension axes each extend at a recess chip-guiding angle in a region of 0° to 45°. A method of using the cutting insert and the workpiece at a standstill and a machining method are also provided.

An assembly of a generally rhombus-shaped reversible cutting insert and a support seat. Each end surface of the cutting insert has a corner abutment surface adjacent each nose cutting edge, at least one inner abutment surface on one side of a lateral plane, and at least one inner abutment surface on the opposite side of the lateral plane, and each corner abutment surface is located closer to a median plane than its adjacent nose cutting edge. In each index position of the cutting insert on the support seat, only one corner abutment surface is in operative contact with one of a plurality of protruding supporting members of the support seat, and only the at least one inner abutment surface located on the opposite side of the lateral plane from the operative corner abutment surface is in contact with the at least one remaining supporting member.

Inclined surfaces are formed on a rake face and a recessed groove is formed in the central portion between the inclined surfaces. A groove width of the recessed groove gradually increases from the position of the end cutting edge toward the rear, then gradually decreases such that the recessed groove has a narrowest portion at a position P2 forward of the position P3 of an upper end of a breaker wall and rearward of a positive rake angle rear end position P1, and then gradually increases toward the rear up to the position P3 of the upper end of the breaker wall. The dimensional relation W1<W2<W3 holds, where W1 is the groove width at the end cutting edge, W2 is the groove width at the narrowest portion, and W3 is the groove width at the position P3 of the upper end of the breaker wall.

A cutting insert may include an upper surface, a lower surface, a front lateral surface and a rear lateral surface. The upper surface may include a first upper cutting edge and an upper constraining surface. The lower surface may include a lower constraining surface. The lower constraining surface may include a lower groove. The lower groove may include a first region, a second region and a third region. The first region may be located on a side opposite to the upper constraining surface. A wedge angle of the first region may be a first angle, a wedge angle of the second region may be a second angle, and a wedge angle of the third region may be a third angle. The first angle may be smaller than each of the second angle and the third angle.

In one aspect, cutting tools are provided comprising radiation ablation regions defining at least one of refractory surface microstructures and/or nanostructures. For example, a cutting tool described herein comprises at least one cutting edge formed by intersection of a flank face and a rake face, the flank face formed of a refractory material comprising radiation ablation regions defining at least one of surface microstructures and surface nanostructures, wherein surface pore structure of the refractory material is not occluded by the surface microstructures and surface nanostructures.

A metal cutting drill insert for a drill tool has opposing top and bottom surfaces with a symmetry axis extending therebetween. At least one stepped cutting edge is configured to cut a continuous chip along the at least one stepped cutting edge. The at least one stepped cutting edge is formed at an intersection of a rake face and an adjoining clearance face of the side surface. In a top view facing the top surface the at least one stepped cutting edge includes a step formed by a transitional edge between a first part and a second part edge. The step extends in a radial direction relative the symmetry axis by a first distance h1, and in a side view facing the side surface the step extends in a direction from the bottom surface towards the top surface by a second distance h2, wherein 0.8.Math.h1≤h2≤1.2.Math.h1.

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.