Abstract: A center cutting or plunging end mill or ball nose end mill has one or more spiral grooves and flutes in the walls of a mill body of cemented tungsten carbide. Each groove includes polycrystalline diamond or cubic boron nitride formed in situ along a leading edge of each flute. Such a groove extends across the cutting end of the mill so that the mill can be used for center cutting or plunging. The vein of diamond-like material may extend to the center of the mill body or may extend almost all of the way to the center, leaving an area of tungsten carbide exposed at the center of the mill body. A high temperature-high pressure press is used for forming the polycrystalline diamond-like veins in situ within the grooves in the mill.

Abstract: A metal cutting insert comprises a carbide substrate, and at least one body of superhard abrasive material, such as PCD or PCBN, bonded to an edge surface of the substrate and extending from one side surface to the other side surface of the substrate. There can be a plurality of superhard bodies disposed at respective corners of the substrate. The abrasive material is applied to the substrate in a container and then sintered and simultaneously bonded to the substrate by an elevated pressure/temperature step. Inserts can be made in rod form (i.e., in one piece) and then the rod can be transversely sliced into thin inserts; or the inserts can be made in separate pieces, with or without separators within the container.

Abstract: A cutting tool of the type having a tool support with a cutting tip of CVD diamond film brazed to it has the diamond material so oriented that the general direction of grain boundaries is not normal to the general plane of the rake face.

Abstract: A milling cutter for milling a workpiece comprising a milling head rotatable about its central longitudinal axis. A milling head carries at least one milling insert of a first grade which presents a cutting edge. The milling head carries a wiper insert of a second grade which presents a wiping edge.

Abstract: A method of making a diamond-coated insert includes, obtaining a substrate of durable and diamond adherent material having a substantially smooth surface on which is coated a diamond layer using any known CVD technique, and partitioning the diamond covered substrate with a laser beam into multiple inserts with desired geometries. If desired, the insert edges and corners may be thereafter machined or ablated until the desired smoothness and finish are achieved, and a fastening throughbore may be preformed or drilled in the center of each insert. The diamond-coated inserts as formed have a top surface entirely coated by a surface layer of diamond of a first thickness, and at least one rake face which is not diamond-coated beyond the surface layer of diamond.

Abstract: A method of manufacturing a diffractive surface comprising: rotating a surface to be cut at a rate W>1,500 RPM; translating a cutting tip at low speed V where V<1.2 mm/minute; and cutting the surface with the cutting tip.

Abstract: A cutting tooth for use in a stump cutting apparatus wherein the cutting tooth comprises a mounting base and a head portion which are integral with one another and are made of a one-piece metallic forging. The forging is preferably made from AMS 4140 steel and the cutting tooth further comprises a cutting tip, preferably of tungsten carbide, which is fixedly attached to the head portion of the tooth. The disclosed preferred embodiments include those in which the head portion is disposed in a substantially straight line relationship with the mounting base and those in which the head portion is curved relative to the mounting base.

Abstract: A preform element, suitable for use as a cutting element on a rotary drill bit, includes a polycrystalline diamond facing table bonded to a tungsten carbide substrate, the rear surface of the facing table being formed with an array of elongate ribs which project from the facing table into the substrate. The array of ribs includes a plurality of pairs of ribs which extend inwardly away from the periphery of the facing table, each pair of ribs being in a generally V-shaped formation so that the ribs diverge as they extend inwardly away from said periphery. Adjacent pairs of ribs may intersect to provide a generally star-shaped formation.

Abstract: In order to improve the wear characteristics of tools with diamond cutting edges, it is proposed to coat the diamond body with a 0.5 to 6 .mu.m thick layer of at least one oxide of the metals zirconium and/or yttrium and/or magnesium and/or titanium and/or aluminum, preferably aluminum oxide. The coating is deposited from the gas phase at gas-phase temperatures up to 800.degree. C. Preferably the pulse-plasma CVD process is used for the coating. The diamond tools so coated are particularly suited for chip-forming machining of carbon-affinitive materials, such as iron-containing materials or steel.

Abstract: A metal cutting insert is made by performing a sintering operation to form a substrate having a longitudinal axis and superhard abrasive bodies bonded thereto at longitudinally spaced locations. The substrate and superhard bodies are sliced-through in directions perpendicular to the axis to form inserts having superhard body portions on both side surfaces of the insert.

Abstract: A preform element, such as a cutting element for a drag-type drill bit, includes a facing table of superhard material having a front face, a peripheral surface, and a rear surface bonded to a substrate which is less hard than the superhard material. The rear surface of the facing table is integrally formed with a plurality of ribs which project into the substrate and extend in directions outwardly away from an inner area of the facing table towards the peripheral surface thereof.

Abstract: A drag bit is formed of an elongate tooth made of tungsten carbide and having an elongate right cylinder construction. The end face is circular at the end of a conic taper. The tapered surface is truncated with two 180.degree. spaced flat faces at 15.degree. to about 45.degree. with respect to the axis of the body. The end is capped by a PDC layer.

Abstract: A cutting tooth for use in a stump cutting apparatus wherein the cutting tooth comprises a mounting base and a head portion which are integral with one another and are made of a one-piece metallic forging. The forging is preferably made from AMS 4140 steel and the cutting tooth further comprises a cutting tip, preferably of tungsten carbide, which is fixedly attached to the head portion of the moth. The disclosed preferred embodiments include those in which the head portion is disposed in a substantially straight line relationship with the mounting base and those in which the head portion is curved relative to the mounting base.

Abstract: An abrasive tool insert comprises a cemented substrate and a polycrystalline diamond layer formed thereon by high pressure, high temperature processing. The interface between the substrate and the diamond layer comprises at least one angled profile wherein said profile slopes downwardly and outwardly toward the periphery of the insert.

Abstract: An abrasive tool insert comprises a cemented metallic substrate and a polycrystalline diamond layer formed thereon by high pressure, high temperature processing. The interface between the substrate and the diamond layer forms a sawtooth shaped cross-sectional profile including a number of surfaces sloping outwardly and downwardly toward a cutting edge of the insert.

Abstract: A tool component comprises an abrasive compact layer bonded to a cemented carbide substrate along an interface. The abrasive compact layer has a working surface, on a side opposite to the interface. This working surface is flat and presents a cutting edge or point around its periphery. A recess extends into the substrate from the interface. The recess has a side wall and a base both of which are located entirely within the carbide substrate. The recess has a portion located in the interface. The area of this portion is at least 25 percent the area of the interface. A material, different to that of the substrate, fills the recess and is bonded to the substrate. This material will typically be abrasive compact of the same type as the abrasive compact layer, or a cemented carbide which has characteristics different to that of the substrate.

Abstract: A rotary drag bit for drilling hard rock formations with substantially planar PDC cutting elements having diamond tables backed by substrates which flare or taper laterally outwardly and rearwardly of the cutting edge of the diamond table. A cutting structure defining a "lipped" cutting edge is also disclosed.

Abstract: A drill bit for cutting hard and abrasive materials has cutting lips formed from sintered polycrystalline diamond (PCD) or polycrystalline cubic boron nitride (PCBN) contained in one or more inserts installed in a drill bit blank. The inserts are made by forming depressions in the upper surface of a matrix slab of tungsten carbide, filling the depressions with fine mesh grains of diamonds or cubic born nitride, subjecting the slab to heat and pressure sufficient to fuse the grains to one another and to the surrounding matrix walls, and then cutting the matrix slab to remove individual inserts containing an elongated vein having an exposed PCD or PCBN surface supported by at least one and preferably two or more side walls of tungsten carbide. A rectangular slot having side walls parallel to one another and equidistant from the diameter of a cylindrical drill bit blank is cut into one transverse end wall of the blank, and one or more inserts placed in the slot.

Abstract: A cutter blade (17) for a finger joint cutter head (10) which includes a cantilevered cutting tip attachment. A cantilever pocket (20) is formed in the fillet area of steel backing member (18) to receive and hold the inner end of a hard material cutting tip (19), such as tungsten carbide. Cantilever pocket (20) has tapered sides which diverge outwardly and a rounded vertex or pocket bottom. Cutter tips are elongated to extend well into cantilever pockets (20). Each cutter tip is attached within a pocket (20) and along the joint surface of steel backing members (18), using a sandwich braze, to form braze joints (21) and (22).

Abstract: A rotary cutter grinder that cuts and grinds upon its circumferential surface is well suited for stump grinding and the like applications. The rotary cutter grinder is constituted by a hub portion for mounting to the power output shaft of a prime mover and plural arms unitary with the hub portion. These arms are substantially uniformly spaced about the hub portion and extend radially outwardly therefrom. A cutting tool, usually a tungsten carbide cutting tool, is mounted to each of the arms at a positive rake angle relative to the perpendicular to the direction of motion by the cutting tool.

Abstract: A cutting tool having a diamond film cutting edge is disclosed. The tool may have a shear cutting angle of up to 25.degree. while maintaining its durability and achieving a high degree of cutting efficiency.

Abstract: A rotary cutting tool has a plurality of helical channels located in the body of the rotary cutting tool. Individual cutter segments are bonded within each helical channel to form a continuous helical cutting edge that is machined to a finished state. An area of the tool body adjacent to the helical channel is removed to create helical flutes. Preferably, the segments are cut from disks of polycrystalline diamond (PCD) or polycrystalline cubic boron nitride (PCBN).

Abstract: A cutting insert for a rotary cutting tool comprises a body of tungsten carbide, with layers of polycrystalline diamond on opposite sides of the body. The diamond layers overlap across the centre-line of the insert. The cutting insert is shaped for retention at the end of the rotary cutting tool so that the first and second sides of the cutting insert are substantially parallel to the axis of the cutting tool, and the diamond layers are offset from one another across the width of the body so that they define the lips or major cutting edges of the cutting tool.

Abstract: A novel hob construction includes a plurality of blades and a cylindrical main body having opposite axial ends. Flanges including axially aligned slots for receiving the blades are located only upon the ends of the main body. A chocking material is provided over the circumferential extent of the main body and between the blades for forming an effective physical extension of the body for bonding the blades to the body and to each other.

Abstract: The invention relates to a cutting tool having twisted edge in a blade part, having a sintered compact with higher hardness and higher wear resistance than a base sintered body buried and affixed along the twisted edge, and its manufacturing method. The blade part of the cutting tool comprises the base sintered body having a twisted groove in the position of forming the twisted edge on the outer circumference, and the sintered compact of high harndess and high wear resistance applied and buried in the twisted groove and affixed to the base sintered body by sintering, and the twisted edge is formed on the sintered compact of high hardness and high wear resistance.

Abstract: A router type cutter (1) has at one end thereof a drive spigot (2) adapted to be clamped in a rotatable toolholder of a machine tool, at least one helix (3) extending part-way along the cutter (1) from the other end, onto a cutting edge of which helix (3) is brazed a tungsten carbide insert (10) having a non-linear cutting profile along its end face (12).

Abstract: The invention provides a method of manufacturing a twist drill having a cutting insert. The method includes the steps of providing a cutting insert which has a prismatic shape and which comprises a layer of abrasive compact which is bonded to a cemented carbide backing. The insert has on a first facet a cutting edge formed by the abrasive compact layer, and on a second facet a seating surface formed predominantly by the cemented carbide backing. The first and second facets define a predetermined first angle with each other. A twist drill is provided, having a seat in its flank. The seat defines a support surface adapted to receive a seating surface of the insert, and is inclined at a predetermined second angle to the face of the drill. The insert is bonded into the seat, so that the cutting edge of the insert defines the major cutting edge of the drill and the first facet of the insert coincides with the face of the drill. The invention includes cutting inserts and twist drills produced by the method.

Abstract: Disclosed is a cutting tool assembly employing a composite hard sintered body as a cutting part comprising a support and a cutting edge; wherein the cutting part is secured on a base made of a cemented carbide or a hard alloy having at least one edge where a recess is formed, the cutting part being formed by bonding a hard sintered body constituting the cutting edge and a cemented carbide or a cermet consituting the support, and said cutting part being secured in the recess by soldering in such a way that the support side may face the recess.

Abstract: Polycrystalline diamond has non-uniform quality along the direction of thickness. The diamond near the rake surface is of better quality. The diamond near the fixation surface is of worse quality. The worse diamond near the fixation surface alleviates a strong stress or absorbs an external shock. Owing to the worse diamond near the fixation surface, the diamond tool excels in chip resistance or toughness. The better diamond near the rake surface heightens abrasion resistance, adhesion resistance and strength.

Abstract: A diamond tool, e.g., cutting tool, dresser, wire drawing die, etc., having excellent wear resistance, heat resistance and oxidation resistance and with an improved tool life is provided, which is mainly composed of a synthetic diamond single crystal containing boron or boron and nitrogen.

Abstract: A diamond cutting tool is disclosed that forms at least a pair of grooves in the shank of the tool. The grooves contain sintered diamond prior to formation of concave flutes next to the grooves. The grooves are angled to form positive or negative cutter rake angles, whichever is desired. The adjacent concave flutes subsequently formed in the shank of the tool begin parallel with the cutting face of the sintered diamond and curve away from the base of the diamond back towards the surface of the shank. Sharpening of the diamond then results in very little removal of the diamond material thus assuring the integrity of the tool.

Abstract: A composite rotary cutting tool and adaptor includes a straight cutting tool, such as a drill bit or the like, having a cylindrical shank adhesively bonded within a close fitting axial bore in an adaptor or gripping member which has an outer circumferential gripping surface larger than the cutting tool shank. The cutting tool shank has at least one helical channel or groove formed therein so as to maintain a substantial portion of the original cylindrical surface area. The adaptor is hardened in a manner to prevent scale formation in the bore, and an anaerobic adhesive is applied within the bore and along the shank and into the helical groove. The shank is inserted into the adaptor bore to effect full wetting between the interfacing surfaces. The assembly is then fixtured in a vertical orientation and heat cured so as to obtain a composite cutting tool and adaptor having high torque and low concentricity run-out and angularity error.

Abstract: A tool for cutting solid material includes a tool body having a recess, and a cutting insert received in the recess. The cutting insert has spacing buttons which engage a surface of the recess to create a space for accommodating a brazing material which secures the insert to the tool body. The surface of the recess includes an annular retaining groove which receives the buttons in order to prevent tilting of the insert prior to brazing.

Abstract: A carbide shank boring bar having a coolant/lubricant bore running axially therethrough fitted with a steel head, said head being machinable to produce a pocket to receive a metal cutter insert wherein said boring bar shank and said steel head have a diameter less than one-half inch and said head is brazed without flux to said boring bar and no flux residue remains in said coolant/lubricant bore upon completion of said brazing. The method of achieving the fusion includes using an atmospheric vacuum chamber to conduct the fusion.

Abstract: A diamond tool 1 comprising a tool tip 5 of boron-containing single-crystal diamond.

Abstract: An end mill forms at least a pair of spiral grooves or flutes in the mill side walls. Each groove includes polycrystalline diamond formed along a leading edge of each flute. A process for forming the diamond edged on the PCD material bonded within the flute.

Abstract: Disclosed herein is a tool bit comprising a shank including a cylindrical base portion having an axis and a diameter, an elongated end portion of generally cylindrical shape and having an axis extending coaxially with the axis of the base portion, a diameter less than the diameter of the base portion, and an outer cylindrical periphery, which shank end portion includes therein a recess extending lengthwise of the end portion and being of right angle shape in a cross-section extending transversely of the end portion axis, which recess cross-section is defined by a long face extending in parallel spaced relation to a radius extending from the end portion axis and including an outer end at the cylindrical outer periphery and an inner end, and a short face extending from the inner end to the cylindrical outer periphery, and a connecting portion joining the end portion and the base portion and tapering from the base portion diameter to the end portion diameter, and a carbide insert brazed in the recess and having

Abstract: A cutter assembly, for a rotary drill bit, comprises a stud to be received in a socket in the surface of the bit body, the stud being formed, adjacent one end, with a plane surface inclined to the longitudinal axis of the stud. A preform cutting element comprises a front surface, a peripheral edge surface, and a flat rear surface which is brazed to the surface on the stud, the peripheral edge surface of the cutting element being wholly exposed. The junction between the peripheral edge surface and the rear surface of the cutting element is chamfered. Any external fillet of brazing alloy is preferably removed or is not allowed to form during brazing, and the space between the chamfer and the surface of the stud may also be free of brazing alloy. Removal of the brazing fillet may also be advantageous in the case of a non-chamfered cutter.

Abstract: An abrasive compact is provided which has a plurality of recesses which may take the form of grooves or holes formed in a major surface thereof. The recesses contain no solid material and serve as crack arrester formations.

Abstract: An end mill forms at least a pair of spiral grooves or flutes in the mill side walls. Each groove includes polycrystalline diamond formed along a leading edge of each flute. A process for forming the diamond edged on the PCD material bonded within the flute.

Abstract: A polycrystal diamond fluted tool is provided which is capable of effecting working with much higher accuracy and longer life as compared with the sintered diamond straight fluted tool of the prior art, and is particularly suitable for finishing working with high accuracy. The tool is produced by forming, by a vapor phase synthesis method, a polycrystal diamond film on the surface of a substrate which has been subjected to helical grinding, then subjecting the product to a chemical treatment to dissolve and remove only the substrate, brazing the resulting polycrystal diamond film in a fluted form to at least a part of the rake face of a tool base metal which has been subjected to helical grinding in a similar manner to the substrate, and then subjecting the brazed tool base metal to working of a flank face to form a cutting edge.

Abstract: A compact blank for use in operations that require very high impact strength and abrasion resistance is disclosed. The compact comprises a substrate formed of tungsten carbide or other hard material with a diamond or cubic boron nitride layer bonded to the substrate. The interface between the layers is defined by topography with irregularities having non-planar side walls such that the concentration of substrate material continuously and gradually decreases at deeper penetrations into the diamond layer.

Abstract: A tool insert having a cemented carbide substrate with a recess formed in one end of the substrate and having an abrasive compact located in the recess and bonded to the substrate. The cemented carbide substrate has two ends joined by a side, and the recess formed in the substrate has a side and a base, with the side sloping inwards towards a center point of the base. The abrasive compact includes a top surface which provides a cutting surface or edge for the tool insert, a bottom surface which is complementary to the base of the recess, and a side surface which is complementary to the side of the recess.

Abstract: This invention comprises a diamond insert grinding process to remove stress riser cracks formed in a critical area of a tungsten carbide insert body. The cracks are caused by leaching of cobalt from the carbide during the process of brazing a tungsten carbide backed polycrystalline diamond disc to the body. A grinding wheel selectively removes material from the intersection of the braze below the depth of the cracks in the tungsten carbide body thereby relieving the stress riser in the critical area of the body.

Abstract: The composite tool (1) comprises a sintered metal carbide support (2) and a polycrystalline diamond active part (3) having an inner surface (4) of metallurgical connection to the support (2) and an outwardly facing working surface (5). The working surface (5) comprises corrugations (7) which are substantially parallel to one another and form successive projecting zones (7) and hollow zone (8) on at leasst a part of the working surface (5). The composite tool is in particular intended for drilling to a great depth, such as drilling oil wells.

Abstract: A diamond cutter consisting of a polycrystalline diamond layer sintered to a cylindrically shaped tungsten carbide substrate is brazed to a cylindrically shaped mounting surface formed at a cutting end of a tungsten carbide insert body. The cylindrically shaped mounting surface of the insert body is the same diameter as the tungsten carbide substrate hence no fillet of braze material can form adjacent the juncture between the substrate and the insert body at the cutting end of the insert thereby minimizing the damaging affect of a leaching process that forms microvoids or cracks in the insert body.

Abstract: A tool insert comprising an abrasive compact bonded to a cemented carbide support. The cutting edge of the tool is provided by the periphery of the compact. A plurality of recesses, each filled with abrasive compact material, extend into the cemented carbide support from the compact/carbide interface. The recesses are arranged in a series of rows, with each recess being staggered relative to its nearest neighbour in an adjacent row.In use, wear of the compact cutting edge occurs and eventually wears down to the carbide/compact interface. Thereafter, the carbide between adjacent recesses wears quicker than the diamond compact material which is located in each recess creating, in effect, a plurality of cutting ridges or projections.

Abstract: A cutting insert with improved chip control and metal cutting capabilities and a toolholder with an improved clamping arrangement for use in combination therewith. The insert includes a first notch disposed in the insert body extending from the cutting end to the mounting end thereof. A top wall of the insert body has a forward section with a cutting edge, a middle section with a second notch extending across substantially the entire insert body and a rearward section. In one embodiment, the forward section of the insert body includes a chipbreaker. In another embodiment, the forward portion includes an advanced cutting material which defines a cutting edge. In yet another embodiment of the insert, the insert body top wall forward section defines the cutting edge and the insert body does not include a chipbreaker.

Abstract: A ball end mill including an elongated body, a center insert, and a plurality of cutting inserts. The center insert and the cutting inserts are mounted on the forward end of the body. The center insert and each of the cutting inserts are adjacent to each other in such a manner that the center insert is located with a part thereof at the center. The center insert which is made of cemented carbide has cutting edges passing through the center axis. The cutting inserts are made of a super hard sintered compact. Each of the cutting inserts has a cutting edge aligned to the cutting edge of the center insert. The cutting edges of the cutting inserts and the center insert cooperate to draw a hemispherical path on rotation.

Abstract: A cutting element, for a rotary drill bit, comprises a tablet having a front face, a rear face and a peripheral edge, at least the front face of the tablet being provided by a layer of superhard material, such as polycrystalline diamond. The peripheral edge of the tablet is formed with one or more re-entrant portions so as to define projecting cutting portions to the sides of the re-entrant portions. The element may be cut from a blank which is initially circular.