The throwaway insert includes a base and a cutting edge member. The cutting edge member includes a rake face, a flank face, a first connecting face, a second connecting face, and a first ridgeline serving as a cutting edge. The rake face includes a main surface and a first chamfer provided at an edge tip portion of the cutting edge member, the edge tip portion including an extreme tip portion of the cutting edge member. In a plan view from an upper surface of the base, the flank face, the first connecting face, and the second connecting face are located external to the base. The first chamfer is inclined relative to the main surface so as to increase a thickness of the cutting edge member as the first chamfer is closer to the main surface.

A cutting insert may include a first surface, a second surface, a third surface, and a land surface. The first surface may include a first corner, a first side, and a second side. The land surface may be inclined relative to the first surface and the third surface. The land surface may include a first land surface connecting to the first corner. An imaginary flat surface orthogonal to a central axis connecting a center of the first surface and a center of the second surface may be a reference plane, a first inclination angle of a part of the first land surface which connects to a midportion of the first corner may be larger than a second inclination angle of a part of the first land surface which connects to an end portion at a side of the first side of the first corner.

A cutting insert in a non-limiting aspect of the present disclosure may include an upper surface, a lower surface, a lateral surface and a cutting edge. The upper surface may include a first corner and a first side. The upper surface may further include a first protrusion and a second protrusion. The first protrusion may be extended toward the first corner. The second protrusion may be located between the first corner and the first protrusion. The first protrusion may include an inclined surface. The inclined surface may be located along the first side. The inclined surface may include a first surface and a second surface. The second surface may be located further away from the first corner than the first surface. The first surface and the second surface may be individually inclined upward as going away from the first side, and having a concave shape as a whole.

A tool body in which a cutting insert can be replaced easily is provided. The tool body which fixes the indexable cutting insert includes an insert mounting seat which is provided on a first surface of the tool body, a clamp member which binds the cutting insert placed on the insert mounting seat, and an operating member which operates the clamp member. The operating member can lower the clamp member from the first surface toward a second surface of the tool body on an opposite side thereof to the first surface and can raise the clamp member from the second surface toward the first surface. The clamp member has a hook portion which is brought into contact with a diameter reducing portion formed on an inner peripheral surface of a mounting hole of the cutting insert in a state where the clamp member is lowered.

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 cutting insert according to an aspect includes a base portion and a cutting portion. The cutting portion includes an upper surface, a side surface, a ridge line including a first ridge line and a second ridge line, and an intersection point. The upper surface includes a top surface region and a rising surface region located between the top surface and the ridge line, and having a shape protruding toward the intersection point. In a top view, a first distance from the first ridge line to the rising surface increases as close to the intersection point, and a second distance from the second ridge line to the rising surface increases as close to the intersection point.

There is provided a cutting insert used for both drilling and turning. The cutting insert includes an insert main body having a front surface and a rear surface, the outline shapes of which are parallelogram shapes, peripheral side surfaces disposed on four sides of the insert main body, cutting edges provided on respective intersecting ridge lines between the front surface and the peripheral side surface and between the rear surface and the peripheral side surface of the insert main body, and a hole provided in the insert main body to incline with respect to the front surface and the rear surface, the hole being usable for attachment.

A cutting insert is described. It has a cutting insert body with a central mounting section and at least one cutting edge. The cutting edge is wave-shaped and generally descending from an end section of the cutting edge towards a middle section of the cutting edge. Furthermore, a chip guiding recess extends substantially along the at least one cutting edge and is arranged between the cutting edge and the central mounting section. A chip breaker element is arranged in the chip guiding recess. The chip breaker element comprises a first portion having a first width and a second portion having a second width, wherein a transition between the first portion and the second portion is formed as a step.

A cutting insert rotatable about an axis, has opposing front and rear surfaces interconnected by an insert peripheral surface, the insert peripheral surface having first and second side surfaces spaced apart by first and second land surfaces. First and second land edges extend along the first and second land surfaces, respectively. A first front edge formed at the intersection of the front surface and the first side surface includes a cutting-edge portion, and a second front edge formed at the intersection of the front surface and the second side surface is devoid of a cutting-edge portion. A cutting profile formed by rotating the cutting-edge portion about the axis is located axially forward of the second front edge. The cutting insert is releasably secured to a tool shank, the cutting insert being located between two protuberances protruding from a forward end portion of the tool shank.

Provided is a method for manufacturing a Fresnel lens mold by performing cutting process on a workpiece with a cutting tool, the Fresnel lens mold having a lens surface and an upright surface alternately arranged. The cutting tool has a first cutting edge having an arc shape with a radius r and a second cutting edge continuous to the first cutting edge. A machining apparatus repeatedly performs a first process of forming, with the first cutting edge, a lens mold surface serving as a mold of a lens surface of a Fresnel lens, and a second process of forming, with the second cutting edge, an upright mold surface serving as a mold of an upright surface of the Fresnel lens to manufacture the Fresnel lens mold.