A cutting insert includes a body made of a ceramic material. The body has a first surface, a second surface and at least one flank surface extending between the first surface and the second surface. The first surface includes a chip forming feature extending in a radially outwardly direction to a cutting edge and extending in a radially inwardly direction to an inner edge. The chip forming feature includes a front wall that slopes downward from the cutting edge radially inward toward a rounded bottom surface and a back wall that slopes upward from the rounded bottom surface radially inward to the inner edge. The chip forming feature can include an optional land surface between the cutting edge and the front wall.

A cutting insert includes a body made of a ceramic material. The body has a first surface, a second surface and at least one flank surface extending between the first surface and the second surface. The first surface includes a chip forming feature extending in a radially outwardly direction to a cutting edge and extending in a radially inwardly direction to an inner edge. The chip forming feature includes a front wall that slopes downward from the cutting edge radially inward toward a rounded bottom surface and a back wall that slopes upward from the rounded bottom surface radially inward to the inner edge. The chip forming feature can include an optional land surface between the cutting edge and the front wall.

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 insert (100,100) includes a body (102) having a top face (104), a bottom face (106) opposite the top face (104), and at least one flank face (108, 110, 112, 114). A coolant inlet aperture (126), a coolant outlet aperture (132, 134), and an internal coolant passage (128, 130) in fluid communication with the coolant inlet aperture (126) and the coolant outlet aperture (132, 134) are formed using electro-magnetic radiation. The coolant inlet aperture (126) can be formed in the top face (104), the bottom face (106) and/or the flank face (108, 110, 112, 114), and the coolant outlet aperture (132, 134) can be formed in any different face (104, 106, 108, 110, 112, 114). A method of forming the internal coolant passages (128, 130) is described.

A cutting insert (100,100) includes a body (102) having a top face (104), a bottom face (106) opposite the top face (104), and at least one flank face (108, 110, 112, 114). A coolant inlet aperture (126), a coolant outlet aperture (132, 134), and an internal coolant passage (128, 130) in fluid communication with the coolant inlet aperture (126) and the coolant outlet aperture (132, 134) are formed using electro-magnetic radiation. The coolant inlet aperture (126) can be formed in the top face (104), the bottom face (106) and/or the flank face (108, 110, 112, 114), and the coolant outlet aperture (132, 134) can be formed in any different face (104, 106, 108, 110, 112, 114). A method of forming the internal coolant passages (128, 130) is described.

Induced material segregation methods of manufacturing a polycrystalline diamond compact (PDC) cutter result in formation of a polycrystalline diamond/tungsten carbide (WC) composite material having a smooth compositional gradient from maximum WC concentration at one face to maximum diamond concentration at another face. Because the compositional gradient is smooth, very little or no mismatch of coefficient of thermal expansion occurs, which improves a service lifetime of the PDC cutter.

Induced material segregation methods of manufacturing a polycrystalline diamond compact (PDC) cutter result in formation of a polycrystalline diamond/tungsten carbide (WC) composite material having a smooth compositional gradient from maximum WC concentration at one face to maximum diamond concentration at another face. Because the compositional gradient is smooth, very little or no mismatch of coefficient of thermal expansion occurs, which improves a service lifetime of the PDC cutter.

A cutting insert (100, 100) includes a body (102) having a top face (104), a bottom face (106) opposite the top face (104), and at least one flank face (108, 110, 112, 114). A coolant inlet aperture (126), a coolant outlet aperture (132, 134), and an internal coolant passage (128, 130) in fluid communication with the coolant inlet aperture (126) and the coolant outlet aperture (132, 134) are formed using electro-magnetic radiation. The coolant inlet aperture (126) can be formed in the top face (104), the bottom face (106) and/or the flank face (108, 110, 112, 114), and the coolant outlet aperture (132, 134) can be formed in any different face (104, 106, 108, 110, 112, 114). A method of forming the internal coolant passages (128, 130) is described.

A cutting insert (100, 100) includes a body (102) having a top face (104), a bottom face (106) opposite the top face (104), and at least one flank face (108, 110, 112, 114). A coolant inlet aperture (126), a coolant outlet aperture (132, 134), and an internal coolant passage (128, 130) in fluid communication with the coolant inlet aperture (126) and the coolant outlet aperture (132, 134) are formed using electro-magnetic radiation. The coolant inlet aperture (126) can be formed in the top face (104), the bottom face (106) and/or the flank face (108, 110, 112, 114), and the coolant outlet aperture (132, 134) can be formed in any different face (104, 106, 108, 110, 112, 114). A method of forming the internal coolant passages (128, 130) is described.

A surface-coated cutting tool includes a base material and a coating formed on the base material. The coating includes an -Al.sub.2O.sub.3 layer containing a plurality of -Al.sub.2O.sub.3 crystal grains. The -Al.sub.2O.sub.3 layer includes: a first region made up of an edge ridgeline, a region A of a rake face, and a region B of a flank face; a second region which is a region of the rake face except for the region A and covered with the coating; and a third region which is a region of the flank face except for the region B. The -Al.sub.2O.sub.3 layer satisfies a relation ba>0.5, where a is an average value of a TC(006) in the first region in texture coefficient TC(hkl) and b is an average value of the TC(006) in the second region or the third region in texture coefficient TC(hkl).