A workpiece applied for use with a cutting machine comprises a first outer surface, a second outer surface and a third outer surface. The third outer surface intersects the first outer surface and the second outer surface to define an extrusion-acting portion having an extruding portion. The workpiece can be used to form a cutter or a trimmed portion thereof. Accordingly, rapid production of cutters by molding machines can be realized, and blades of the molding machine for machining a produced cutter become readily replaceable. While a blade portion is machining, the extrusion-acting portion is applied to support and guide the workpiece, such that the surface machined by the blade portion can be extruded and polished simultaneously. Thus, machining qualities of the cutter, including finish, straightness and roundness, manufactured by applying the workpiece for the molding machine can be significantly improved.

A cutting edge has a corner cutting edge, a flat drag, and a main cutting edge. The rake surface has a first rake surface portion, a second rake surface portion, and a third rake surface portion. The first rake surface portion has a first inclined surface inclined at a first angle. The second rake surface portion has a second inclined surface inclined at a second angle greater than the first angle. The first end portion and the second end portion are higher than the reference surface in a direction perpendicular to the reference surface, and the main cutting edge extends so as to intersect the reference surface when viewed in a direction parallel to the reference surface. A first step portion rising from the third rake surface portion and continuous with the first rake surface portion is provided on the rake surface.

A round double-sided cutting insert includes an insert peripheral surface that includes a plurality of angularly spaced apart indexing latches protruding therefrom and a plurality of cylindrical insert side abutment surfaces that circumferentially alternate with the plurality of indexing latches. An insert holder has a pocket peripheral surface which includes at least one indexing gap and a plurality of pocket side abutment surfaces that circumferentially alternate with the at least one indexing gap. When the cutting insert is releasably attached to the insert holder, to constitute a fastened position of a cutting tool, each of the plurality of pocket side abutment surfaces abuts a respective insert side abutment surface and each indexing gap has a respective indexing latch located therein.

The present invention provides a cutting insert 10 which is mounted on an indexable rotating tool E comprising a body B that rotates about a predetermined rotational axis AX. The cutting insert 10 comprises an upper surface 10a, a lower surface 10b and a peripheral side surface. The cutting insert 10 further comprises an inner cutting edge 10g and a corner cutting edge 10f. A top part S, which has the maximum distance from the lower surface 10b, is located on the corner cutting edge 10f.

A surface-coated cutting tool includes a base material and a coating. A hard layer in the coating includes a plurality of crystal grains having a sodium chloride-type crystal structure. When the angle of intersection between the normal direction to (111) plane that is a crystal plane of the crystal grain and the normal direction to the surface of the base material is measured, a proportion A of the crystal grains having the angle of intersection of 0 degree or more to less than 20 degrees is 50% or more. The length of 3 grain boundaries is less than 50% of the length of 3-29 grain boundaries. The crystal grain has a layered structure in which a first layer and a second layer are alternately stacked. The total thickness of the first layer and the second layer adjacent to each other is 3 to 40 nm.

Provided is a coated cutting tool, comprising: a substrate; and a coating layer formed on at least part of a surface of the substrate. The coating layer includes at least one composite nitride layer including a compound having a composition represented by (Ti.sub.xAl.sub.y)N [x denotes an atomic ratio of a Ti element based on a total of the Ti element and an Al element, y denotes an atomic ratio of the Al element based on a total of the Ti element and the Al element, and 0.10x0.50, 0.50y0.90, and x+y=1 are satisfied]. The composite nitride layer includes a phase having a lattice constant of from 0.400 nm or more to 0.430 nm or less, and a phase having a lattice constant of from 0.755 nm or more to 0.810 nm or less.

A cutting insert includes a base body and a coating layer, and also includes a rake surface, a flank surface, and a cutting edge located along an intersecting ridge therebetween. The rake surface includes an outer peripheral part and a middle part protruded relative to the outer peripheral part. The middle part includes a constraining surface. The outer peripheral part includes a first breaker part, a second breaker part, and the third breaker part adjacent to the constraining surface. The constraining surface is configured by the base body and the coating layer does not exist at the constraining surface. A skewness Rsk of a roughness curve at the constraining surface is ?1.5 ?m to ?0.5 ?m. A skewness Rsk at the third breaker part is ?0.2 ?m or less. The skewness Rsk at the constraining surface is smaller than the skewness Rsk at the third breaker part.

In a cutting insert of an embodiment of the present invention, an upper surface includes a first corner, and a second corner and a third corner respectively adjacent to both sides of the first corner. The upper surface sequentially includes a rake surface located along an upper cutting edge and inclined toward a lower surface as going inward from the upper cutting edge at a rake angle on a basis of a perpendicular plane perpendicular to a central axis extending between the upper and lower surfaces, and a connection surface located more inward than the rake surface and inclined toward the lower surface as going inward at a connection angle on the basis of the perpendicular plane. An intersecting part of the rake surface and the connection surface includes a highest position in a portion of the intersecting part corresponding to the minor rake surface. A cutting tool with the cutting insert, and a method of producing a machined product by using the cutting tool are also provided.

A double-sided, indexable cutting insert for a milling cutter includes a first surface, a second surface, and side surfaces. Cutting edges are defined at an intersection between the first and second surfaces and side surfaces. Each cutting edge includes a first cutting-edge portion, a second cutting-edge portion and a third cutting-edge portion. The first and second surfaces include diagonally opposite recessed regions. The cutting insert is mounted in a milling cutter defining a radial rake angle, A, and a ramping angle, B, with respect to a central, rotational axis of the milling cutter that provide superior performance for both milling and ramping cutting operations.

The invention relates to an apparatus for processing cylinder walls of internal combustion engines (1), including a cutting element (4). The cutting element (4) is arranged on a rotary cutting ring (3). The cutting element (4) has a slit contour (5) with a plurality of cutting edges (6) arranged next to each other in a direction of an axis of rotation of the rotary cutting ring. And, the individual cutting edges (6) face in a direction of rotation of the rotary cutting ring.