A cemented carbide and a coated cemented carbide each include a Zr carboxide. The cemented carbide includes a hard phase containing main component tungsten carbide and a binder phase containing at least one main component element selected from the group consisting of Co, Ni and Fe. The cemented carbide includes 75 to 95 mass % of the hard phase and 5 to 25 mass % of the binder phase in an inner region inner than 500 m below a surface of the cemented carbide. The hard phase includes a Zr carboxide; and Zr.sub.sur/Zr.sub.in is from 0.25 to 0.80 when an average content of the Zr carboxide in a surface region which ranges from the surface of the cemented carbide to a depth of 500 m therebelow is denoted by Zr.sub.sur and an average content of the Zr carboxide in an inner region inner than the surface region is denoted by Zr.sub.in.

A drill includes a cutting edge. The cutting edge has a point angle which is continuously decreased from a center-position point angle A (herein, 0<A<180) at a center position to a maximum-diameter-position point angle of 0 at a maximum diameter position. The cutting edge has a relief angle which is continuously decreased from the center position to the maximum diameter position. The cutting edge of the drill has a relief angle at the maximum diameter position. Hence, the cutting edge also serves as a cutting edge for reaming. The ridgeline and relief face of the cutting edge have no corner, thereby providing good wear resistance.

A method for drilling an element to be drilled by a drilling device and a cutting tool including drill margins and cutting edges. The method includes determining at least one load value representing overall drag due to internal friction of the drilling device and to friction of drill margins in the element to be drilled. Determining includes: stopping a drilling operation in progress; partial retraction of the cutting tool on a predetermined distance, the predetermined distance being chosen such that the cutting edges are no longer in contact with the element to be drilled; driving the cutting tool with predetermined cutting parameters; measuring at least one load value during the driving of the cutting tool with the cutting parameters before its cutting edges again come into contact with the element to be drilled and after stabilization of the load values, the measured load value representing the overall drag.

A mounting tool (1) for mounting a friction-welding boss (9), wherein the mounting tool (1) includes a drive shaft (2) with a first end section (3) adapted to create a detachable force coupling with the friction-welding boss (9) or an adapter and a holder is arranged spring-loaded at the first end section (3) and at least one cutting means (6) is arranged at the holder (5). A milling adapter (10) includes a first end section (11) adapted to create a detachable force coupling with a mounting tool (1), and a second end section (12) including at least one cutting means (13).

A drill bit for drilling laminates includes at least two main chip flutes separated by corresponding webs. The free end faces of the webs form relief surfaces. At least one secondary flute, which is formed in the periphery of each of the webs divides the web into a main and a secondary web. A main cutting edge is formed by the intersection of a main chip flute and a relief surface on the main web. A secondary cutting edge is formed by the intersection of the secondary flute with a relief surface on the secondary web following the main cutting edge in the direction of operation, the main cutting edges extending to the nominal radius of the drill. The secondary cutting edges terminate at a distance before the nominal radius and axially project from the main cutting edge by an axial overhang at least along their radially outer section.

Apparatus and methods for performing and controlling the sequence of steps in a multi-step machining process utilizing a plurality of drilling units, where each drilling unit is configured to perform at least one step of the multi-step machining process. Air pressure sensors in each drilling unit measure air pressures at the surface of a workpiece where the cutting tool of the drilling unit is engaged, which measured air pressures indicate air flow at the surface. These air flows in turn indicate the state of the machining at the surface of the workpiece, and based on the state of the machining, a machine control system will determine whether a drilling unit can perform its particular machining operation in the proper sequence on the workpiece.

A coated tool part of a machining tool, having a substrate coated with a wear layer and with a bonding layer disposed between the substrate and the wear layer. The wear layer and the bonding layer each have a plurality of sub-layers arranged one on top of another. Each sub-layer includes a first individual ply, a second individual ply, and a third individual ply, wherein the three individual plies in the plurality of sub-layers are arranged one on top of another in a regularly alternating sequence. The first individual ply includes Al.sub.x1Me.sub.1-x1(N.sub.y1C.sub.1-y1). The second individual ply includes Al.sub.x2Me.sub.1-x2(N.sub.y2C.sub.1-y2). The third individual ply includes Al.sub.x3Me.sub.1-x3-z3Si.sub.z3(N.sub.y3C.sub.1-y3). A ply thickness of the third individual plies included in the bonding layer varies from sub-layer to sub-layer such that the ply thickness of the third individual ply in a sub-layer disposed further down, closer to the substrate.

A surface-coated cutting tool according to the present invention includes a coating. The coating has an -Al.sub.2O.sub.3 layer. The -Al.sub.2O.sub.3 layer includes a lower layer portion and an upper layer portion. When respective crystal orientations of crystal grains of -Al.sub.2O.sub.3 are specified by performing EBSD analyses with an FE-SEM on a cross-section obtained when the -Al.sub.2O.sub.3 layer is cut along a plane including a normal line of a surface of the -Al.sub.2O.sub.3 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 -Al.sub.2O.sub.3 layer is equal to or more than 90%, and such an area in the lower layer portion is equal to or less than 50%.

A match drilling tool comprising a body comprising a drilling leg and a fixing leg, said drilling leg being separated from said fixing leg by a gap, wherein said drilling leg defines a cutter guide opening, and wherein said fixing leg defines an alignment pin opening, said alignment pin opening being concentric with said cutter guide opening; and an alignment pin slideably received in said alignment pin opening.

A surface-coated cutting tool according to the present invention includes a coating. The coating has an -Al.sub.2O.sub.3 layer. The -Al.sub.2O.sub.3 layer includes a lower layer portion and an upper layer portion. When respective crystal orientations of crystal grains of -Al.sub.2O.sub.3 are specified by performing EBSD analyses with an FE-SEM on a cross-section obtained when the -Al.sub.2O.sub.3 layer is cut along a plane including a normal line of a surface of the -Al.sub.2O.sub.3 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 -Al.sub.2O.sub.3 layer is equal to or more than 90%, and such an area in the lower layer portion is equal to or less than 50%.