The present disclosure relates to a coated cutting tool including a substrate and a coating disposed on the substrate, wherein the coating includes a layer of Ti.sub.xZr.sub.yAl.sub.(1-x-y)N, where 0<x≦0.3, 0.2≦y≦0.8 and 0.1≦(1-x-y)≦0.7. The disclosure further relates to a method of producing such a coated cutting tool, and to a cutting insert forming a coated cutting tool.

A cutting tool comprises a substrate and a coating that coats the substrate, the coating including an α-alumina layer provided on the substrate, the α-alumina layer including crystal grains of α-alumina, the α-alumina layer including a lower portion and an upper portion, the upper portion being occupied in area at a ratio of 50% or more by crystal grains of α-alumina having a (006) plane with a normal thereto having a direction within ±15° with respect to a direction of the normal to the second interface, the lower portion being occupied in area at a ratio of 50% or more by crystal grains of α-alumina having a (006) plane with a normal thereto having a direction within ±15° with respect to the direction of the normal to the second interface, the α-alumina layer having a thickness of 3 μm or more and 20 μm or less.

A cutting tool for machining titanium alloy or superalloy includes a Me-B-N coating. The Me-B-N coating is Me1-B-N; Me1 is one or more selected from transition metal elements Hf, V, Nb, Ta and Mo, and the atomic percentage of each element is: Me1: 8-40%, B: 15-60%, and N: 10-65%; and the Me-B-N coating includes Me1Nx phase and BN phase; or, the Me-B-N coating is Me1-Me2-B-N, Me1 is one or more selected from transition metal elements Hf, V, Nb, Ta and Mo; Me2 is one or more selected from transition metal elements Ti, Zr, Cr, and W; and the atomic percentage of each element is: Me1: 4-36%, Me2: 4-36%, B: 15-60%, and N: 10-65%; and the Me-B-N coating includes Me1Nx phase, Me2Nx phase and BN phase.

A cutting tool comprises a rake face and a flank face, the cutting tool being composed of a substrate made of a cubic boron nitride sintered material and a coating provided on the substrate, the coating including a MAlN layer, when a cross section of the MAlN layer is subjected to an electron backscattering diffraction image analysis to determine a crystal orientation of each of the crystal grains of the M.sub.xAl.sub.1−xN and a color map is created based thereon, then on the color map, the flank face having the MAlN layer occupied in area by 45% to 75% by crystal grains of the M.sub.xAl.sub.1−xN having a (111) plane with a normal thereto extending in a direction within 25 degrees with respect to a direction in which a normal to the flank face extends, the MAlN layer having a residual stress of −2 GPa to −0.1 GPa.

A coated cutting tool comprises a substrate and a coating layer formed on a surface of the substrate, and has a rake face and a flank. The coating layer comprises an alternating laminate structure in which first compound layers containing AlN and second compound layers containing a compound are laminated in an alternating manner, the compound having a composition represented by formula (1) below:

(Ti.sub.1-xAl.sub.x)N  (1)

(wherein x satisfies 0.40≤x≤0.70). An average thickness T.sub.1 per first compound layer is 5 nm or more to 160 nm or less, and an average thickness T.sub.2 per second compound layer is 8 nm or more to 200 nm or less. A ratio of T.sub.1 to T.sub.2 is 0.10 or more to 0.80 or less. An average thickness T.sub.3 of the alternating laminate structure is 2.5 μm or more to 7.0 μm or less. A ratio (H/E) of hardness H to elastic modulus E is 0.065 or more to 0.085 or less at the rake face or the flank.

Provided is a cutting tool including a base material and a coating layer provided on the base material, the coating layer including a titanium carbonitride layer provided on the base material, an intermediate layer provided on the titanium carbonitride layer in contact therewith, and an alumina layer provided on the intermediate layer in contact therewith, the intermediate layer being composed of a compound made of titanium, carbon, oxygen, and nitrogen, the intermediate layer having a thickness of more than 1 μm, when P.sub.N1 atomic % represents an atomic ratio of the nitrogen in an interface between the intermediate layer and the alumina layer, and P.sub.N2 atomic % represents an atomic ratio of the nitrogen at a point A away from the interface by 1 μm on a side of the intermediate layer, a ratio P.sub.N1/P.sub.N2 of the P.sub.N1 to the P.sub.N2 being more than or equal to 1.03.

A cutting tool including a rake face, a flank face, and a cutting edge portion, comprising a substrate and an AlTiN layer, the AlTiN layer including cubic Al.sub.xTi.sub.1-xN crystal grains, A1 having an atomic ratio x of 0.7 or more and less than 0.95, the AlTiN layer including a central portion, the central portion at the rake face being occupied in area by (200) oriented Al.sub.xTi.sub.1-xN crystal grains at a ratio of 50% or more and less than 80%, the central portion at the cutting edge portion being occupied in area by (200) oriented Al.sub.xTi.sub.1-xN crystal grains at a ratio of 80% or more.

A method for producing a coated cutting tool includes depositing on every flank face and every rake face of the cutting tool an Al.sub.2O.sub.3 layer by a HIPIMS process during two-fold or three-fold rotation of the substrates, at a substrate temperature ≥350° C. but <600° C., the deposited Al.sub.2O.sub.3 layer including α-Al.sub.2O.sub.3.

A cutting tool includes: a substrate; a hard layer provided on the substrate; and a titanium carbonitride layer provided on the hard layer, wherein a thickness of the titanium carbonitride layer is more than or equal to 2 μm, a hardness of the titanium carbonitride layer at a room temperature is more than or equal to 35 GPa, and a Young's modulus of the titanium carbonitride layer at the room temperature is more than or equal to 800 GPa.

A cutting tool comprises a substrate and an AlTiN layer, the AlTiN layer including cubic Al.sub.xTi.sub.(1-x)N crystal grains, an atomic ratio x of Al in the Al.sub.xTi.sub.(1-x)N being 0.7 or more and 0.95 or less, the AlTiN layer including a first major surface on a side of a surface of the cutting tool and a second major surface on a side of the substrate, the AlTiN layer including a first region having a distance of 0 nm or more and 100 nm or less from the first major surface, and a second region having a distance of more than 100 nm and 150 nm or less from the first major surface, the first region having a maximum oxygen content ratio of 5 atomic % or more and 30 atomic % or less, the second region having a maximum oxygen content ratio of less than 5 atomic %.