Abstract: 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<XR?0.9, 0.65<XF?0.9, 0.4?XE?0.7, XR?XE?0.2, and XF?XE?0.2 being satisfied, with a composition of the TiAlN layer in a cutting edge region located in the cutting edge being expressed as Ti1-XEAlXEN, a composition thereof in a rake face region located in the rake face being expressed as Ti1-XRAlXRN, and a composition thereof in a flank face region located in the flank face being expressed as Ti1-XFAlXFN.

Abstract: A hard coating includes two first crystalline phases, and a second crystalline phase disposed between the two first crystalline phases. The two first crystalline phases each include, independently, a laminate structure having a Ti1-x1Alx1N phase having a sodium chloride-type crystal structure, and an Alx2Ti1-x2N phase having a sodium chloride-type crystal structure that are alternately stacked. An Al composition ratio x1 of the Ti1-x1Alx1N phase satisfies a relationship 0.5?x1?0.75, and an Al composition ratio x2 of the Alx2Ti1-x2N phase satisfies a relationship 0.75<x2?0.95. The laminate structure includes a region in which an Al concentration periodically changes along a stacking direction of the Ti1-x1Alx1N phase and the Alx2Ti1-x2N phase. In this region, a difference between a maximum value of the Al composition ratio x2 and a minimum value of the Al composition ratio x1 is greater than 0.25. The second crystalline phase contains AlN having a wurtzite-type crystal structure.

Abstract: A hard coating includes two first crystalline phases, and a second crystalline phase containing AlN of a wurtzite-type crystal structure disposed therebetween. The two first crystalline phases each include, independently, a laminate structure having a Ti1-x1Alx1N phase having a sodium chloride-type crystal structure, and an Alx2Ti1-x2N phase having a sodium chloride-type crystal structure that are alternately stacked. An Al composition ratio x1 satisfies a relationship 0.5?x1?0.75, and an Al composition ratio x2 satisfies a relationship 0.75<x2?0.95. The laminate structure includes a region in which an Al concentration periodically changes along a stacking direction of the Ti1-x1Alx1N phase and the Alx2Ti1-x2N phase. In this region, a difference between a maximum value of the Al composition ratio x2 and a minimum value of the Al composition ratio x1 is greater than 0.25.

Abstract: A surface-coated cutting tool includes a base material and a coating formed on the base material. The coating includes an ?-Al2O3 layer. The ?-Al2O3 layer contains ?-Al2O3 crystal grains and sulfur, and has a TC(006) of more than 5 in texture coefficient TC(hkl). The sulfur has a concentration distribution in which a concentration of the sulfur decreases in a direction away from a base-material-side surface of the ?-Al2O3 layer, in a thickness direction of the ?-Al2O3 layer.

Abstract: 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<XR?0.9, 0.65<XF?0.9, 0.4?XE?0.7, XR?XE?0.2, and XF?XE?0.2 being satisfied, with a composition of the TiAlN layer in a cutting edge region located in the cutting edge being expressed as Ti1-XEAlXEN, a composition thereof in a rake face region located in the rake face being expressed as Ti1-XRAlXRN, and a composition thereof in a flank face region located in the flank face being expressed as Ti1-XFAlXFN.

Abstract: A surface-coated cutting tool according to the present invention is provided with a base material and a coating formed on the base material, the coating includes an ?-Al2O3 layer, the ?-Al2O3 layer includes a plurality of crystal grains of ?-Al2O3 and shows (001) orientation, a grain boundary of the crystal grains contains a CSL grain boundary and a general grain boundary, and a length of a ?3 crystal grain boundary out of the CSL grain boundary exceeds 80% of a length of a ?3-29 crystal grain boundary and is equal to or more than 10% and equal to or less than 50% of the total length of all grain boundaries which is the sum of the length of the ?3-29 crystal grain boundary and a length of the general grain boundary.

Abstract: A surface-coated cutting tool according to the present invention includes a coating. The coating includes an ?-Al2O3 layer. Each of the ?-Al2O3 layers on a side of a rake face and a side of a flank face shows (001) orientation. In the ?-Al2O3 layer on the rake face side, a length LR3 of a ?3 crystal grain boundary exceeds 80% of a length LR3-29 of a ?3-29 crystal grain boundary and is not lower than 10% and not higher than 50% of a total length LR of all grain boundaries. In the ?-Al2O3 layer on the flank face side, a length LF3 of a ?3 crystal grain boundary exceeds 80% of a length LF3-29 of a ?3-29 crystal grain boundary and is not lower than 10% and not higher than 50% of a total length LF of all grain boundaries. A ratio LR3/LR3-29 is higher than a ratio LF3/LF3-29.

Abstract: A surface-coated cutting tool according to the present invention includes a coating. The coating includes an ?-Al2O3 layer. Each of the ?-Al2O3 layers on a side of a rake face and a side of a flank face shows (001) orientation. In the ?-Al2O3 layer on the rake face side, a length LR3 of a ?3 crystal grain boundary exceeds 80% of a length LR3-29 of a ?3-29 crystal grain boundary and is not lower than 10% and not higher than 50% of a total length LR of all grain boundaries. In the ?-Al2O3 layer on the flank face side, a length LF3 of a ?3 crystal grain boundary exceeds 80% of a length LF3-29 of a ?3-29 crystal grain boundary and is not lower than 10% and not higher than 50% of a total length LF of all grain boundaries. A ratio LR3/LR3-29 is lower than a ratio LF3/LF3-29.

Abstract: A surface-coated cutting tool includes a base material and a coating formed on the base material. The coating includes an ?-Al2O3 layer. The ?-Al2O3 layer contains a plurality of ?-Al2O3 crystal grains and a plurality of ?-Al2O3 crystal grains, and has a TC(006) of more than 5 in a texture coefficient TC(hkl). A ratio of C? to a sum of C? and C?: [C?/(C?+C?)×100](%) is 0.05 to 7%, where C? is a total number of peak counts of the ?-Al2O3 crystal grains obtained from measurement data of x-ray diffraction for the coating, and C? is a total number of peak counts of the ?-Al2O3 crystal grains obtained from the measurement data of the x-ray diffraction for the coating.

Abstract: A surface-coated cutting tool includes a base material and a coating formed on the base material. The coating includes an ?-Al2O3 layer containing a plurality of ?-Al2O3 crystal grains. The ?-Al2O3 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 ?-Al2O3 layer satisfies a relation b?a>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).

Abstract: A surface-coated cutting tool includes a base material and a coating formed on the base material. The coating includes an ?-Al2O3 layer containing a plurality of ?-Al2O3 crystal grains. The ?-Al2O3 layer includes a lower layer portion disposed at a side of the base material, an intermediate portion disposed on the lower layer portion, and an upper layer portion disposed on the intermediate portion. In a crystal orientation mapping performed on a polished cross-sectional surface of the ?-Al2O3 layer using an EBSD, an area ratio of ?-Al2O3 crystal grains with (001) orientation in the lower layer portion is less than 35%, an area ratio of ?-Al2O3 crystal grains with (001) orientation in the intermediate portion is 35% or more, and an area ratio of ?-Al2O3 crystal grains with (001) orientation in the upper layer portion is less than 35%.

Abstract: A coating included in a surface-coated cutting tool according to the present invention has an ?-Al2O3 layer. In a 15-?m square color map of a processed surface in parallel to a surface of the ?-Al2O3 layer, an area A1 occupied by coarse crystal grains A is ?50% and an area A2 in the area A1 occupied by crystal grains having a (001) plane orientation is ?90%, an area B1 occupied by medium-sized crystal grains B of ?-Al2O3 is 20 to 50%, an area B2 in the area B1 occupied by crystal grains having the (001) plane orientation is ?90%, an area C1 occupied by fine crystal grains C of ?-Al2O3 is 10 to 50%, an area C2 in the area C1 occupied by crystal grains having the (001) plane orientation is ?50%.

Abstract: A surface-coated cutting tool according to the present invention includes a coating. The coating has an ?-Al2O3 layer. The ?-Al2O3 layer includes a lower layer portion and an upper layer portion. When respective crystal orientations of crystal grains of ?-Al2O3 are specified by performing EBSD analyses with an FE-SEM on a cross-section obtained when the ?-Al2O3 layer is cut along a plane including a normal line of a surface of the ?-Al2O3 layer and a color map is prepared based on the crystal orientations, in the color map, an area in the upper layer portion occupied by the crystal grains of which normal direction of a (001) plane is within ±10° with respect to a normal direction of the surface of the ?-Al2O3 layer is equal to or more than 90%, and such an area in the lower layer portion is equal to or less than 50%.

Abstract: A surface-coated cutting tool includes a base material and a coating formed on the base material. The coating includes an ?-Al2O3 layer. The ?-Al2O3 layer contains a plurality of ?-Al2O3 crystal grains and a plurality of ?-Al2O3 crystal grains, and has a TC(006) of more than 5 in a texture coefficient TC(hkl). A ratio of C? to a sum of C? and C?: [C?/(C?+C?)×100](%) is 0.05 to 7%, where C? is a total number of peak counts of the ?-Al2O3 crystal grains obtained from measurement data of x-ray diffraction for the coating, and C? is a total number of peak counts of the ?-Al2O3 crystal grains obtained from the measurement data of the x-ray diffraction for the coating.

Abstract: A surface-coated cutting tool includes a base material and a coating formed on the base material. The coating includes an ?-Al2O3 layer containing a plurality of ?-Al2O3 crystal grains. The ?-Al2O3 layer includes a lower layer portion disposed at a side of the base material, an intermediate portion disposed on the lower layer portion, and an upper layer portion disposed on the intermediate portion. In a crystal orientation mapping performed on a polished cross-sectional surface of the ?-Al2O3 layer using an EBSD, an area ratio of ?-Al2O3 crystal grains with (001) orientation in the lower layer portion is less than 35%, an area ratio of ?-Al2O3 crystal grains with (001) orientation in the intermediate portion is 35% or more, and an area ratio of ?-Al2O3 crystal grains with (001) orientation in the upper layer portion is less than 35%.

Abstract: A surface-coated cutting tool includes a base material and a coating formed on the base material. The coating includes an ?-Al2O3 layer containing a plurality of ?-Al2O3 crystal grains. The ?-Al2O3 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 ?-Al2O3 layer satisfies a relation b?a>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).

Abstract: A surface-coated cutting tool includes a base material and a coating formed on the base material. The coating includes an ?-Al2O3 layer. The ?-Al2O3 layer contains ?-Al2O3 crystal grains and sulfur, and has a TC(006) of more than 5 in texture coefficient TC(hkl). The sulfur has a concentration distribution in which a concentration of the sulfur decreases in a direction away from a base-material-side surface of the ?-Al2O3 layer, in a thickness direction of the ?-Al2O3 layer.

Abstract: A surface-coated cutting tool according to the present invention includes a coating. The coating includes an ?-Al2O3 layer. Each of the ?-Al2O3 layers on a side of a rake face and a side of a flank face shows (001) orientation. In the ?-Al2O3 layer on the rake face side, a length LR3 of a ?3 crystal grain boundary exceeds 80% of a length LR3-29 of a ?3-29 crystal grain boundary and is not lower than 10% and not higher than 50% of a total length LR of all grain boundaries. In the ?-Al2O3 layer on the flank face side, a length LF3 of a ?3 crystal grain boundary exceeds 80% of a length LF3-29 of a ?3-29 crystal grain boundary and is not lower than 10% and not higher than 50% of a total length LF of all grain boundaries. A ratio LR3/LR3-29 is lower than a ratio LF3/LF3-29.

Abstract: A surface-coated cutting tool according to the present invention includes a coating. The coating has an ?-Al2O3 layer. The ?-Al2O3 layer includes a lower layer portion and an upper layer portion. When respective crystal orientations of crystal grains of ?-Al2O3 are specified by performing EBSD analyses with an FE-SEM on a cross-section obtained when the ?-Al2O3 layer is cut along a plane including a normal line of a surface of the ?-Al2O3 layer and a color map is prepared based on the crystal orientations, in the color map, an area in the upper layer portion occupied by the crystal grains of which normal direction of a (001) plane is within ±10° with respect to a normal direction of the surface of the ?-Al2O3 layer is equal to or more than 90%, and such an area in the lower layer portion is equal to or less than 50%.

Abstract: A surface-coated cutting tool according to the present invention includes a coating. The coating includes an ?-Al2O3 layer. Each of the ?-Al2O3 layers on a side of a rake face and a side of a flank face shows (001) orientation. In the ?-Al2O3 layer on the rake face side, a length LR3 of a ?3 crystal grain boundary exceeds 80% of a length LR3-29 of a ?3-29 crystal grain boundary and is not lower than 10% and not higher than 50% of a total length LR of all grain boundaries. In the ?-Al2O3 layer on the flank face side, a length LF3 of a ?3 crystal grain boundary exceeds 80% of a length LF3-29 of a ?3-29 crystal grain boundary and is not lower than 10% and not higher than 50% of a total length LF of all grain boundaries. A ratio LR3/LR3-29 is higher than a ratio LF3/LF3-29.