A coated tool in a non-limiting embodiment of the present disclosure includes a base and a coating film located on the base. The coated tool includes a first surface, a second surface adjacent to the first surface, and a cutting edge located on at least a part of a ridge part of the first surface and the second surface. The coating film includes an AlTiN film. The coating film has a first compressive stress σ11 in a first direction which is parallel to a surface of the base and intersects with the cutting edge at an angle of 90°, and a second compressive stress σ22 in a second direction which intersects with the first direction at an angle of 90°. The first compressive stress σ11 is different from the second compressive stress σ22.

A surface-coated cutting tool according to the present invention includes a tool body and a hard coating layer including a complex carbonitride layer containing a small amount of chlorine and (Ti.sub.(1-x)Zr.sub.xyHf.sub.x(1-y))(N.sub.(1-z)C.sub.z) (0.10≤x≤0.90, 0<y≤1.0, 0.08<z<0.60), a ZrHf and C content ratios in cycles, a cycle distance between a maximum ZrHf content point and an adjacent minimum ZrHf content point and a cycle distance between a maximum C content point and an adjacent minimum C content point are 5 to 100 nm, an average value of content ratio differences Δx and Δz is 0.02 or more, a distance between the maximum ZrHf content point and the maximum C content point is ⅕ or less of the distance between a maximum content point and a minimum content point of adjacent ZrHf components, and a composition fluctuation structure is 10% or more.

A surface-coated cutting tool including a tool substrate containing WC crystal grains and insulating grains, and a coating layer composed of a multiple nitride of Ti, Al, and V and disposed on the surface of the tool substrate. The multiple nitride is represented by a compositional formula: Ti.sub.aAl.sub.bV.sub.cN satisfying the following relations:
0.25≤a≤0.35,
0.64≤b≤0.74,
0<c≤0.06, and
a+b+c=1
wherein each of a, b, and c represents an atomic proportion. The coating layer is characterized by exhibiting a peak attributed to a hexagonal crystal phase and a peak attributed to a cubic crystal phase as observed through X-ray diffractometry.

A method for manufacturing a cutting tool includes: the cutting tool comprising a tool body made of a sintered alloy, a hard coating which is disposed on an outer surface of the tool body and has at least a layer formed of any of a carbide, a nitride, and a carbonitride, or a composite compound thereof, and a cutting edge which is formed at a ridge portion of the tool body and includes a portion of the hard coating located at the ridge portion, a laser peening step of directly irradiating the hard coating with a pulsed laser having a pulse width of 100 ps or less to apply compressive residual stress to the hard coating and a surface region of the tool body.

A cemented carbide may include a hard phase including W and C, and a binder phase including cubic Co. The binder phase may include Zr. The Co may include a lattice constant of more than 3.5575 Å and not more than 3.5600 Å. A coated tool may include a coating layer located on a surface of the cemented carbide. A cutting tool may include a holder that is extended from a first end toward a second end and may include a pocket on a side of the first end, and the coated tool located in the pocket.

A long twist drill includes a shank and a drill body having a drill tip (16). The twist drill has a length L and an outer diameter D, and has a cemented carbide or high speed steel substrate and a coating of at least one layer. The quota L/D is at least 16. The twist drill has two cutting segments at the tip and two flutes chip. The twist drill is provided with holes for fluid opening in the tip. The twist drill has an axial web thinning angle GAA, which is 40 to 50°. The twist drill further has a web that back tapers such that a web diameter gets smaller in a direction away from the tip towards the shank within an axial distance.

Disclosed is a hard coating including a chemical composition specified by formula: (Ti.sub.aAl.sub.bSi.sub.cR.sub.d)O.sub.x, where R represents at least one rare-earth element; and a, b, c, d, and x are atomic ratios respectively of Ti, Al, Si, R, and O. The atomic ratios meet conditions as specified by formulae: 0.30≦a≦0.7, 0.30≦b≦0.70, 0≦c≦0.2, 0.005≦d≦0.05, a+b+c+d=1, and 0.5≦a/b<1. The atomic ratios meet a condition as specified by Formula (1) when R does not include Ce. The atomic ratios meet a condition as specified by Formula (2) when R includes Ce. The hard coating has better wear resistance as compared with conventional nitride films and oxide films.
0.8≦[x/(2a+1.5b+2c+1.5d)]≦1.2  (1)
0.8≦[x/(2a+1.5b+2c+2d)]≦1.2  (2)

A cutting tool comprising a base material and a coating arranged on the base material; wherein: the coating comprises an α-Al.sub.2O.sub.3 layer composed of a plurality of α-Al.sub.2O.sub.3 particles; the average particle diameter a of the α-Al.sub.2O.sub.3 particles in a first region of the α-Al.sub.2O.sub.3 layer is 0.10 μm or more and 0.30 μm or less; the average particle diameter b of the α-Al.sub.2O.sub.3 particles in a second region of the α-Al.sub.2O.sub.3 layer is 0.30 μm or more and 0.50 μm or less; the average particle diameter c of the α-Al.sub.2O.sub.3 particles in a third region of the α-Al.sub.2O.sub.3 layer is 0.30 μm or more and 0.50 μm or less; and the ratio b/a is 1.5 or more and 5.0 or less.

A drill is provided with a body having a rod shape configured to rotate about a rotational axis, a cutting edge that is located at a tip portion of the body and extends from an outer periphery of the body toward the rotational axis when viewed from the tip portion, a flank located at the tip portion and disposed along the cutting edge, a covering layer that covers at least the tip portion of the body, and one or more recessed portions disposed on the flank at positions close to the cutting edge.

Disclosed are rare earth metal containing silicate coatings, coated articles (e.g., heaters and susceptors) or bodies of articles and methods of coating such articles with a rare earth metal containing silicate coating.