A cutting edge configuration of a cutting tool for performing a cutting process on a surface (21) of a workpiece (19), the cutting tool including a rake face (3) provided with first and second cutting edges (11, 13), the cutting tool being moved relative to the surface-to-be-cut (21) with the first and second cutting edges (11, 13) cutting thereinto to thereby perform the cutting process, wherein the first cutting edge (11) is positioned ahead of the second cutting edge (13) in a cutting direction (z-direction) of the cutting tool to provide the rake face (3) with a feed-direction (y-direction) rake-angle, and the cutting tool is fed in a direction from a side of the second cutting edge (13) to a side of the first cutting edge (11).

A method of processing a workpiece with a first surface and a second surface facing away therefrom includes the following principal steps: (i) blocking the workpiece with the aid of a blocking material on a blocking member with the blocking material between blocking member and first surface, (ii) processing the workpiece by a geometrically defined cutting edge at the second surface for achieving the desired macrogeometry, (iii) processing the workpiece by a geometrically undefined cutting edge at the second surface for achieving the desired microgeometry and (iv) deblocking the workpiece from the blocking member. The principal step (ii) includes a plunge-cutting sub-step (ii.2) in which by a geometrically defined cutting edge an encircling plunge cut is produced which extends through the first surface as far as into the blocking material so that the workpiece with a predetermined edge profile remains on the blocking member radially within the plunge cut.

A cutting insert has a cutting corner, having a bisector, located on a top surface of the cutting insert. A chip-control arrangement is located at the cutting corner. The chip-control arrangement includes a projection protruding from the top end face and that extends longitudinally in a direction transverse to, and to opposites sides of, the bisector. The chip-control arrangement also includes a protrusion protruding from the top end face and comprising a protrusion ridge that extends from the projection towards a corner cutting edge at the cutting corner.

The present invention provides a cutting tool which comprises a cutting tool insert with a tip portion of cBN material having a cutting edge formed therein and a base portion forming a sintered composition with the tip portion, and a body portion coupling the cutting tool insert with a shank of the cutting tool, wherein the cutting tool insert has a rake face and a first flank face defining the cutting edge. The rake face has a negative rake angle relative to an axis parallel to a center axis of the body portion. A second flank face defining a further edge with the first flank face is formed such that the cutting edge and the further edge do not have a common vertex. The second flank face is tilted with respect to an axis parallel to a center axis of the body portion by an angle greater than 0.

A cutting tool (2)in particular a rotary toolis described, having a cutting edge (4) from which a rake face (6) and a clearance face (8) extend, characterized in that a groove (12) is introduced into the clearance face (8) in a region along the cutting edge (4) so that a part of the clearance face (8) is formed as a wear face (14) that extends between the groove (12) and the cutting edge (4) and is bounded by the groove (12) and the cutting edge (4). The groove (12) advantageously limits the wear of the cutting tool (2) in the region of the cutting edge (4) on the wear surface (14), so that overall the frictional forces that occur are kept small and the service life of the cutting tool (2) is extended. Furthermore, a cutting element for a cutting tool (2) as well as a method for manufacturing the cutting tool (2) are described.

A cutting tool 1 includes a cutting edge 2, a rake face 4 and a flank 5 and is used for cutting a surface of a cylindrical or columnar work W by a skiving process. The cutting tool 1 is configured to satisfy a relational expression:

tan.sup.1(cos /cos()tan.sup.1(cos.sup.1(r/r))<90

where denotes a rake angle, denotes an inclination angle of the cutting edge 2 with respect to the rotation axis A, denotes an angle between a feed direction of the cutting tool 1 and a direction orthogonal to a rotation axis A in a plane view of the cutting tool 1 and the work W, r denotes a radius of an outer circumferential surface of the work W before processing, and r denotes the radius of the outer circumferential surface of the work W after processing.

The present invention provides a cutting tool which comprises a cutting tool insert with a tip portion of cBN material having a cutting edge formed therein and a base portion forming a sintered composition with the tip portion, and a body portion coupling the cutting tool insert with a shank of the cutting tool, wherein the cutting tool insert has a rake face and a first flank face defining the cutting edge. The rake face has a negative rake angle relative to an axis parallel to a centre axis of the body portion. A second flank face defining a further edge with the first flank face is formed such that the cutting edge and the further edge do not have a common vertex. The second flank face is tilted with respect to an axis parallel to a centre axis of the body portion by an angle greater than 0.

A method of processing a workpiece with a first surface and a second surface facing away therefrom includes the following principal steps: (i) blocking the workpiece with the aid of a blocking material on a blocking member with the blocking material between blocking member and first surface, (ii) processing the workpiece by a geometrically defined cutting edge at the second surface for achieving the desired macrogeometry, (iii) processing the workpiece by a geometrically undefined cutting edge at the second surface for achieving the desired microgeometry and (iv) deblocking the workpiece from the blocking member. The principal step (ii) includes a plunge-cutting sub-step (ii.2) in which by a geometrically defined cutting edge an encircling plunge cut is produced which extends through the first surface as far as into the blocking material so that the workpiece with a predetermined edge profile remains on the blocking member radially within the plunge cut.

A cutting tool has an insert holder and a cutting insert releasably attached thereto. The cutting insert has an insert edge which includes two nose cutting edges and a convex corner cutting edge which extends therebetween. The two nose cutting edges form a nose angle. The insert edge also includes two mid-side edges which are located further from the corner cutting edge than the nose cutting edges. The two mid-side edges form a mid-side angle. The nose angle is less than the mid-side angle.