A surface-coated cutting tool includes a base material and a coating covering the base material. The base material includes a rake face and a flank face. The coating includes a TiCN layer. The TiCN layer has a (422) orientation in a region d1 in the rake face. The TiCN layer has a (311) orientation in a region d2 in the flank face.

A cutting tool holder of the present disclosure includes a bar-shaped main body. The main body includes a first pocket to receive a first insert, a second pocket to receive a second insert, a first groove extending from the first pocket, and a second groove extending from the second pocket. The first groove includes a second opening located on a rear side in a rotation direction, and the second groove includes a fourth opening located on a rear side in the rotation direction in a cross section orthogonal to a rotation axis. An angle θ1 formed by the second opening and an outer peripheral surface of the main body is smaller than an angle θ2 formed by the fourth opening and the outer peripheral surface of the main body in a cross section orthogonal to the rotation axis.

A surface-coated cutting tool includes a base material and a coating covering the base material. The base material includes a rake face and a flank face. The coating includes a TiCN layer. The TiCN layer has a (422) orientation in a region d1 in the rake face. The TiCN layer has a (311) orientation in a region d2 in the flank face.

A surface coated cutting tool having surfaces including a rake face and a flank face and a cutting edge defined by a boundary portion between the rake face and the flank face includes a substrate and a coating which covers the surfaces of the substrate, the coating having a TiAlN layer having an NaCl type crystal structure, and relation of 0.65<XR0.9, 0.65<XF0.9, 0.4XE0.7, XRXE0.2, and XFXE0.2 being satisfied, with a composition of the TiAlN layer in a cutting edge region located in the cutting edge being expressed as Ti.sub.1-XEAl.sub.XEN, a composition thereof in a rake face region located in the rake face being expressed as Ti.sub.1-XRAl.sub.XRN, and a composition thereof in a flank face region located in the flank face being expressed as Ti.sub.1-XFAl.sub.XFN.

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.

A cutting tool holder of the present disclosure includes a bar-shaped main body. The main body includes a first pocket to receive a first insert, a second pocket to receive a second insert, a first groove extending from the first pocket, and a second groove extending from the second pocket. The first groove includes a second opening located on a rear side in a rotation direction, and the second groove includes a fourth opening located on a rear side in the rotation direction in a cross section orthogonal to a rotation axis. An angle 1 formed by the second opening and an outer peripheral surface of the main body is smaller than an angle 2 formed by the fourth opening and the outer peripheral surface of the main body in a cross section orthogonal to the rotation axis.

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.

A surface coated cutting tool having surfaces including a rake face and a flank face and a cutting edge defined by a boundary portion between the rake face and the flank face includes a substrate and a coating which covers the surfaces of the substrate, the coating having a TiAlN layer having an NaCl type crystal structure, and relation of 0.65<XR0.9, 0.65<XF0.9, 0.4XE0.7, XRXE0.2, and XFXE0.2 being satisfied, with a composition of the TiAlN layer in a cutting edge region located in the cutting edge being expressed as Ti.sub.1-XEAl.sub.XEN, a composition thereof in a rake face region located in the rake face being expressed as Ti.sub.1-XRAl.sub.XRN, and a composition thereof in a flank face region located in the flank face being expressed as Ti.sub.1-XFAl.sub.XFN.