The present invention relates to a cutting tool, which performs, like a drill or a ball end mill, cutting while rotating in a state in which the center of the tip end is in contact with a work material, and includes a wear-resistant layer formed at the tip end thereof, wherein a portion of the wear-resistant layer is selectively removed through tip end polishing from the center of the tip end of the drill or the ball end mill to a predetermined area, so as to restrain micro-brittle wear generated in an ultra-low speed region, and thus remarkably improving the cutting lifespan of the cutting tool such as the drill or the ball end mill.

The present invention relates to a cutting tool, which performs, like a drill or a ball end mill, cutting while rotating in a state in which the center of the tip end is in contact with a work material, and includes a wear-resistant layer formed at the tip end thereof, wherein a portion of the wear-resistant layer is selectively removed through tip end polishing from the center of the tip end of the drill or the ball end mill to a predetermined area, so as to restrain micro-brittle wear generated in an ultra-low speed region, and thus remarkably improving the cutting lifespan of the cutting tool such as the drill or the ball end mill.

A rotary cutting blade material has an attaching structure forming portion that is to serve as an attaching portion to the shank, a cutting structure forming portion that is to serve as a cutting blade, and a joint portion. The cutting structure forming portion has a core portion and a surface portion provided on the attaching structure forming portion with the joint portion being interposed, and the surface portion covers at least a part of a surface of the core portion. The attaching structure forming portion includes a hard material including a hard component and one or two or more types of iron group elements, and the hard material has a Young's modulus of not more than 350 GPa. The core portion includes a cemented carbide material, and the surface portion includes PCD or CBN.

A metal cutting tool includes a main body made of cemented carbide, cermet, ceramic, steel or high-speed steel, and a multi-layer wear protection coating. The wear protection coating includes a lower layer having an overall composition of Ti.sub.m Al.sub.(1-m) N with 0.25<m<0.55 and an overall thickness of 500 nm to 3 m. The lower layer has 50 to 600 pairs of alternately stacked sub-layers in a sequence (A-B-A-B- . . . ) and having a composition Ti.sub.a Al.sub.(1-a)N with 0.45a0.55 and a thickness of 1 nm to 10 nm. The upper layer has 30 to 400 triples of alternately stacked sub-layers in a sequence (C-D-E-C-D-E- . . . ). The sub-layers of the upper layer have a composition Ti.sub.x Al.sub.ySi.sub.z N with x+y+z=1 and 0.20x0.45, 0.20y0.45 and 0.20z0.45 and a thickness of 1 nm to 10 nm.

A hard coating, which is to disposed to cover a surface of a tool substrate, has a total thickness of 0.5-20 m and includes an A layer and nanolayer-alternated layer that are alternately laminated by physical vapor deposition. The nanolayer-alternated layer includes a B layer and C layer that are alternately laminated. The A layer has a thickness of 50-1000 nm and is AlCr(SiC) nitride that is represented by a composition formula of [Al.sub.1-W-XCr.sub.W(SiC).sub.X]N wherein an atomic ratio W is 0.20-0.80 and an atomic ratio X is 0.01-0.20. The B layer has a thickness of 1-100 nm and is TiAl nitride that is represented by a composition formula of [Ti.sub.1-YAl.sub.Y]N wherein an atomic ratio Y is 0.30-0.85. The C layer has a thickness of 1-100 nm and is Ti(SiC) nitride represented by a composition formula of [Ti.sub.1-Z(SiC).sub.Z]N wherein an atomic ratio Z is 0.05-0.45. The nanolayer-alternated layer has a thickness of 50-1000 nm.

To improve the adhesion resistance and wear resistance of a surface-coated cutting tool. The surface-coated cutting tool includes a tool substrate, and a single-component coating layer composed of a composite nitride of Cr (chromium), Al (aluminum), and V (vanadium) and disposed on the surface of the tool substrate. The composite nitride is characterized by being represented by a compositional formula: Cr.sub.aAl.sub.bV.sub.cN satisfying the following relations:

0.11a0.26;

0.73b0.85;

0<c0.04; and

a+b+c1

(wherein a, b, and c each represent an atomic proportion). The single-component coating layer has both a hexagonal phase and a cubic phase.

A solid carbide milling cutter has a substrate of hard metal and a multi-layer coating deposited at least to surface regions that contact a workpiece during a milling operation. The multi-layer coating includes a single-layer or a multi-layer functional layer deposited directly on the substrate surface and a single-layer or a multi-layer covering layer deposited on the functional layer. The functional layer has one or more layers of Ti.sub.xAl.sub.1-xN with 0.3x0.55. The covering layer has one or more layers of ZrN. The functional layer and the covering layer are deposited by HIPIMS, wherein during the deposition of the functional layer power pulses are applied to each sputtering target consisting of material to be deposited, which power pulses transfer an amount of energy to each sputtering target that exceeds a maximum power density in the pulse of 500 W/cm.sup.2.

To provide a tool that ensures improved durability even when a diamond coating containing boron is formed. A diamond coating (40) includes a first layer (41) that is formed as a layer on a surface layer side of the diamond coating (40) and is regarded as containing no boron, and a second layer (42) positioned on a side of a base material (30) with respect to the first layer (41) and contains at least 1000 ppm or more of the boron. Since the first layer (41) with a larger compressive stress is formed on the surface layer of the diamond coating (40), a crack generation from the surface layer side of the diamond coating (40) during the process can be reduced. Consequently, the durability of a tool (1) can be improved even when the diamond coating (40) containing 1,000 ppm or more of boron is formed.

A coated cutting tool comprising a substrate and a coating layer provided on a surface of the substrate, wherein: the coating layer comprises at least one -type aluminum oxide layer; and a texture coefficient TC (0,0,12) of a (0,0,12) plane of the -type aluminum oxide layer is from 4.0 or more to 8.4 or less; and a texture coefficient TC (1,0,10) of a (1,0,10) plane thereof is from 0.4 or more to 3.0 or less.

It is an object to provide a rotating tool having an excellent wear resistance. The rotating tool includes: a base member including a cutting edge portion and a flute portion; and a coating film that coats a surface of the base member, a ratio B/A of a film thickness B of the coating film coating a surface of the flute portion to a film thickness A of the coating film coating a surface of the cutting edge portion being not less than 0.8.