Abstract: A drill blank, particularly a blank for a micro-drill, comprises an elongate cylindrical cemented carbide body, having flat end surfaces, a recess formed in one end surface and taking the form of an island in that surface wholly surrounded by cemented carbide, and an abrasive compact located in the recess, bonded to a cemented carbide, and presenting a surface coincident with the carbide end surface in which the recess is located. A drill may be formed from the drill blank by suitably shaping the cemented carbide body, for example, by fluting, in the region of the abrasive compact to expose the abrasive compact.

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: The present invention provides a metal bonded abrasive tool wherein the tool has improved life and mechanical properties. The invention further includes the bond composition which allows for improved life and mechanical properties, particularly in diamond blade dressing tools.

Abstract: Improved razors and razor blades and processes for producing razor blades or similar cutting tools with sharp and durable cutting edges, by hard-carbon coating of blades with amorphous diamond, preferably using a filtered cathodic arc plasma source. A coating of amorphous diamond having at least 40 percent sp3 carbon bonding, a hardness of at least 45 gigapascals and a modulus of at least 400 gigapascals is applied to the sharpened edge of a substrate. The substrate may be mechanically honed, and there is no interlayer between the substrate and the amorphous diamond coating. The coating imparts stiffness and rigidity to a thin blade while maintaining a high aspect ratio.

Abstract: A method of manufacturing a metal bonded abrasive product such as a saw or drill segment or bead for a diamond wire is provided. The method includes the steps of providing a mixture of the metal, in particulate form, and the abrasive particles, cold pressing the mixture to the desired final shape at a pressure in the range 320 to 1500 MPa to produce a cold pressed product at a temperature in the range 900 to 1300.degree. C. under conditions which inhibit degradation of the abrasive particles and the particulate metal. The product, after free sintering, will generally have a relatively high porosity, for example, a porosity of 10 to 25 percent by volume.

Abstract: A method for manufacturing cutting tools having diamond-like cutting edges or surfaces which are formed by bonding high shear compaction diamond or cubic boron nitride (CBN) ropes or strips in helical grooves formed on the cutting tool outer surface. The strips are formed by slitting a sheet of high shear compaction diamond or CBN material. The ropes are formed by rolling the strips between grooved rollers.

Abstract: Thin walled metal alloy receptacles are filled with a filler material. If granular, the filler material is solidified in the receptacles. The receptacles are inserted in a bit mold with their open ends abutting against preformed cutter locations in the bit mold. The mold is filled with a steel or tungsten carbide powder and a binder and exposed to temperatures sufficient to cause the binder to infiltrate the steel or tungsten carbide as well as infiltrate the receptacle outer surfaces, metallurgically bonding the receptacles to the binder. The mold is then removed, revealing a bit body with the bonded filled receptacles. The filler material is removed from the receptacles PCD cutters are inserted in the receptacles and are brazed using conventional brazing techniques.

Abstract: A cutter for soft materials is described. The cutter is made from a conventional cutting instrument such as a dental drill bit having hard particles embedded in the tip surface. The cutter is ground at the tip end so as to remove particles which leave cavities around the peripheral fiat ground tip end. The open cavities and the sharp edges around them provide an effective cutting edge with which soft materials can be cut in clean even lines.

Abstract: The present invention relates to buttons, inserts and bodies for rock drilling, rock cutting, metal cutting and wear part applications. The buttons, inserts and bodies comprise cemented carbide provided with bodies and/or layers of CVD- or PVD-fabricated diamond and then HP/HT treated in the diamond stable area. The bodies of cemented carbide may have a uniform structure or a multi-structure containing eta-phase surrounded by a surface zone of cemented carbide free of eta-phase.

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 preform element, such as a cutting element for a drag-type drill bit, includes a facing table of superhard material having a front cutting 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 protuberances, such as ribs or studs, which project into the substrate. The depth to which the protuberances project into the substrate varies in irregular manner across the facing table, so as to inhibit the propagation of cracks across the substrate to the rear of the facing table.

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

Abstract: An insert for a drill bit is set forth. The insert is formed with an elongate body, typically having a cylindrical cross section terminating at an exposed outer end. The outer end is covered with a polycrystalline disc. In the present disclosure, the polycrystalline disc is reinforced with an insert which is wholly captured in the polycrystalline material. In one form, a circular disc is set forth. In another aspect, multiple reinforcing members can be incorporated. They have the form of multiple discs. This reduces stress concentration in the polycrystalline clad insert.

Abstract: A method of manufacturing a rotary drill bit includes the steps of forming the bit body with a plurality of sockets, inserting in each socket a projecting carbon former, applying a fusible hard facing material to the surface of the bit body, and around the formers, by the localised application of heat to the solid material so as to melt it and weld it to the surface of the bit body, and then replacing the formers with cutters. During the application of the hard facing material, each former is also heated by the application of heat directly to it, so as to raise the temperature of the former to a level greater than the temperature to which it would otherwise be raised solely by conduction of heat from the hard facing material.

Abstract: A method of manufacturing drilling crowns for cylindrical diamond drilling tool bits affords a waste-free fabrication of the drilling crowns impregnated with diamond particles. In a first step an annular axially extending middle or intermediate zone impregnated with diamond particles is joined at each of its opposite end by sintering to a different annular metal end zone. In a second step the intermediate zone is laser cut to form two similar drilling crowns with circumferentially spaced teeth. The teeth form diamond segments providing economical fabrication and a high quality connection with the end zones.

Abstract: An improved earth-boring bit the rolling cone variety and an insert for use therein is provided. A superabrasive element is coated with at least one layer of metallic material. The superabrasive element then is placed in a receptacle cavity in a pre-formed hard metal jacket. The superabrasive element then is brazed or infiltrated to the hard metal jacket. Metallurgical and mechanical bonds between the superabrasive element, the at least one layer of metallic material on superabrasive element, the braze or infiltrant binder material, and the fracture-tough material of the hard metal jacket retain the superabrasive element in the cavity of the hard metal jacket. Improved earth-boring bits according to this embodiment of the present invention provide abrasion-resistant earth-boring bits of the rolling cutter variety. Such improved bits, and the inserts therefore, are formed without resort to high-temperature, high-pressure processes.

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: 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 hardness 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 drill bit including at least one rolling cutter body with rows of relatively hard substantially outwardly projecting and circumferentially spaced cutting inserts projecting from the cutter body and having effective erosion reducing features by application of hardfacing materials placed in oriented regular patterns and shapes on designated critical and vulnerable cutter body areas. The cutter body is produced by a method wherein the body is marked in specific locations of desired patterns, shapes, or boundaries, and, then, hardfacing is applied in these specific boundaries to avoid the insert hole locations. After the hardfacing is permanently bonded to the specified areas, the holes are drilled and the hard cutting inserts are pressed into the holes.

Abstract: The precise cutting of thin wafers from blocks or rods of hard and brittle material by means of ribbon or wire saws requires a very high strength of the sawing ribbon material or sawing wire material. In the method according to the invention, seamless metal rings are cold-rolled to form ribbon loops, optionally divided to form narrower ribbon loops or to form wire loops and optionally provided with a cutting coating. In this way, extremely strong cutting tools can be obtained.

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 invention relates to tool having working surfaces (5) which transmit torque by application against a workpiece and are provided with particles of friction material (8) consisting of metallic or mineral material, such as quartz and/or diamond chips, attached by metallic embedment, and for optimal development of the working surface for the transmission of torque there is an electroplated metallic base layer (7) for solely surface application of the particles of friction material (8) of an embedment layer (9) for the particles of friction material which is then also electroplated, the thickness (x) of the base layer (7) being less than that of the embedment layer (9) and the thickness (y) of the latter being less than the particle size of the particles of friction material (8).

Abstract: A method of forming a substantially hemispherically shaped diamond cutting element for use in a rotary drill bit is provided. A natural diamond is obtained and then cleaved to form a planar surface. A portion of the diamond is trimmed in the shape of a first truncated cone by directing a laser toward the planar surface from a predetermined angle and rotating the diamond in a circle about the central axis. The excess diamond produced by the trimming step is removed by directing the laser toward the diamond, from a direction substantially parallel to the planar surface, and rotating the diamond in a circle about the central axis. Then, a second truncated cone is created by directing a laser toward a lower portion of the first truncated cone from a predetermined angle and rotating the diamond in a circle about the central axis. If desired, the trimming and removing steps are alternately repeated, and the predetermined angle of the laser is successively adjusted.

Abstract: Disclosed is a method for the production of diamond films, which comprises introducing a diamond-forming gas into a reaction chamber in which a substrate is located, activating the gas in the reaction chamber and depositing diamond on the substrate by decomposition of the gas, wherein the diamond-forming gas is a gas or gas mixture containing hydrogen, oxygen and carbon atoms at an atomic ratio satisfying requirements represented by the following formulae:2.gtoreq.C/H.gtoreq.0.0005, and4.gtoreq.O/C.gtoreq.0.0005.

Abstract: An enlarged diamond table for use as a cutter in rotating drill bits is provided by disposing a plurality of thermally stable or leached polycrystalline diamond (PCD) rod-like elements within a matrix body. In one embodiment the matrix body is impregnated with diamond grit and completely fills the interstitial spaces between the plurality of PCD elements. Generally, the PCD elements have their longitudinal axes arranged in a mutually parallel configuration. The bundle of rod-like diamond elements are in one embodiment in a compact touching array and in another embodiment in a spaced-apart array. In the illustrated embodiment, a bundle of rod-like diamond elements are disposed so that their end surfaces are exposed on the cutting face of the cutting slug. The slug is then in turn mounted on a stud or directly infiltrated into a matrix body bit.

Abstract: A diamond cutting table having the geometric characteristics of larger unleached diamond compact products and yet characterized by the physical properties of smaller leached diamond products is fabricated by forming a diamond cutter incorporating a plurality of polycrystalline diamond (PCD) leached disks. The PCD leached disks are disposed in array in a cutting slug formed of matrix material. The matrix material is disposed between and around the plurality of diamond disks and in one embodiment incorporates a volume distribution of diamond grit. The cutting slug is hot pressed or infiltrated to form an integral mass or table. The diamond table is then bonded to a cutter or directly molded into an integral tooth within a matrix body bit.

Abstract: A method of producing a composite cutting insert for a twist drill includes the steps of cutting an intermediate blank from a composite diamond compact. The intermediate blank comprises a relatively broad tungsten carbide strip with a relatively narrow polycrystalline diamond strip at one edge. First and second cutting insert halves are cut from the intermediate blank, each cutting insert half defining a cutting edge of the diamond material. The cutting insert halves are arranged back-to-back to form a composite cutting insert, with the cutting edges on opposite sides of a central plane. The cutting edges are arranged to define a chevron shaped composite cutting edge. The cutting insert halves are preferably brazed together to form a unitary cutting insert. The invention extends to a method of producing a twist drill including the steps of forming a slot-shaped seat diametrally in the end of a twist drill body, and brazing the composite cutting insert into the seat.

Abstract: In an improved single piece earth boring bit of the type having a body including a solid bit face on one end and a shank on the opposite end for connection in a drill string, an improved cutting structure having diamond filled compacts used as a wear resistant inserts. The improved compacts have hard metal jackets and integrally formed diamond cores. The improved compacts are advantageously used as wear resistant inserts in the gage and heel rows of the bit.

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: In an improved earth boring bit of the type having one or more rotable cones secured to bearing shafts, an improved cutting structure having diamond filled compacts used as a wear resistant inserts. The improved compacts have hard metal jackets and integrally formed diamond cores. The improved compacts are advantageously used as gage and heel row compacts when inserted in mating recesses provided on the exteriors of the rotatable cones.

Abstract: A composite for cutting in subterranean formations comprises a cemented carbide substrate and a diamond layer adhered to a surface of the substrate. That surface includes a plurality of spaced apart ridges forming grooves therebetween. The diamond layer has a thickness greater than a depth of the grooves and occupies the grooves to interlock with the substrate. The diamond is comprised of a substantially uniform distribution of diamond particles having a grain size in a range of about 25-75 microns. The ridges are spaced radially inwardly from an outer periphery of the substrate, whereby the diamond layer includes an annular ring portion completely surrounding the plurality of ridges to provide radial reinforcement against the formation and propagation of cracks tending to occur in the vicinity of the ridges.

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 two-part investment casting process is described which involves first casting a hard material shell (32) such as stellite, which is threaded or profiled internally to allow attachment to a pre-machined shank (44) such that the advantages of a fluid and wear resistant investment casting of complex shape may be combined with a tough and machinable shank to allow attachment to the drill string.

Abstract: A method of manufacturing a cutter assembly for a rotary drill bit includes the step of bonding to a carrier a cutting element which comprises a thin hard facing layer already bonded to a less hard backing layer, the backing layer having a greater coefficient of thermal expansion than the hard facing layer. In order to compensate for convex deformation of the rear surface of the backing layer, when the cutting element is heated during the bonding process, the rear surface is made initially concave at ambient temperature. Alternatively, or additionally, the co-operating surface of the carrier may be concave.

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: A rotary diamond tool for truing a grinding wheel, comprising one or two circular vapor-deposited base plates each having a thin diamond layer formed by a vapor deposition process such as electron assisted chemical vapor deposition or direct current plasma chemical vapor deposition. The diamond truing tool is further provided with a pair of backup plates brazed on both side surfaces of the one or two circular vapor-deposited base plates so that the stiffness of the diamond truing tool is increased.

Abstract: A drag bit mold fabricated from high temperature resisting material is machined to accept cylindrically shaped polycrystalline diamond cutters (PCD) having tungsten carbide bodies. Each of the multiple PCD matrix pockets in the mold is formed by two independent non-parallel end mill passes. The first end mill cut defines the PCD cutter position in the cutting face of the matrix diamond drag bit. The second end mill cut superimposed over the first end mill pocket creates a surrounding pocket which fills with powder metallurgy matrix material to provide support for the cylindrical 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: The brazing seams that attach cutting edge wear inserts on a drill are protected against wear and erosion. The inserts are deliberately differentially sized so that the points where the brazing seams that attach them intersect the cutting edges are differentially spaced from the drill center line. Then, a notch is cut into each cutting edge just wide and deep enough to prevent the brazing seam from contacting the cut. Cutting is still complete, despite the notches, since they do not overlap.

Abstract: The inserts and pockets in an inserted drill are provided with differing curvatures on their arcuate back edges. Consequently, when the insert is aligned in the pocket, a crescent shaped, instead of annular, gap is created, with minimal or no thickness at the outboard ends. Very little braze seam is thus exposed to erosion at the cutting edge, but the braze seam is as strong or stronger than conventionally. It is also easier to maintain the desired thickness of the braze seam during manufacture.

Abstract: A co-aptive surgical instrument has a pair of opposite facing co-aptive surfaces for grasping tissue. The co-aptive surfaces are formed with a matrix layer which is preferably of a metal such as nickel with a plurality of hard crystalline particles which are preferably a diamond grit which is captured in the matrix. To insure sufficient capture of the particles in the matrix so as to avoid loss of particles while at the same time providing the maximum possible protrusion of the particles and maximum coverage of the surface by such particles, the particles are oriented in juxtaposition to evenly cover the surface and the matrix is made to have a depth which is at least fifty percent of the average diameter of the particles.

Abstract: A wire drawing die blank is produced by providing an abrasive compact core, having top and bottom surfaces and a side surface, depositing a thin layer of high melting metal such as nickel, iron, chromium or cobalt on the side surface, the coating substantially following the contour of the side surface, providing a support having a hole extending therethrough, the hole having a cross-section larger than that of the core and allowing for the core to be located therein, locating the core in the hole leaving a space between the metal coating and the support, introducing a suitable braze, preferably in liquid form, in the space and causing the braze to bond the core to the support.

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 diamond cutter for use in a drill bit having a geometric size and shape normally characterized by unleached diamond product, such as STRATAPAX diamond cutters, can be fabricated by assembling a plurality of prefabricated leached polycrystalline diamond (PCD) elements in an array in a cutting slug. A cutting slug is formed of matrix material which in one embodiment is impregnated with diamond grit. The cutting face of the cutting slug is characterized by exposing at least one surface of each of the PCD elements disposed therein. The diamonds may be set within the cutting slug either in a compact touching array or in a spaced-apart relationship. More than one type of array may also be employed within a single cutting slug. The PCD elements can assume a variety of polyhedral shapes such as triangular prismatic elements, rectangular elements, hexagonal elements and the like. The plurality of diamond elements and the cutting slug are fabricated using hot pressing or infiltration techniques.

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: An abrasive is provided having an active phase comprising a sintered product comprising diamond grains, each grain being linked directly to its neighbors by bridging to exhibit a polycrystalline structure, and a support consisting essentially of tungsten carbide. The tungsten carbide support comprises a chromium binder phase including 6 to 15% of carbide. The relative proportions by weight of nickel and chromium of the binder phase vary from 60 to 90% to 40 to 100%, respectively. The abrasive is made by placing a layer of diamond grains into a cupel, covering this layer with a tungsten carbide layer including a nickel-chromium mixture to provide the support, subjecting the stack thus produced to a temperature and a pressure sufficient to cause sintering in the plastic phase of the diamond grains and to assure the binding of the compact thus obtained on the support. Drilling and machine tools can be equipped with the abrasive product of the invention.

Abstract: A diamond tipped twist drill for drilling holes in a work piece consists of a body forming a pair of flutes, each flute forming a channel that essentially parallels the flutes. Each channel ends at an aperture formed in the body nearest a cutting end of the drill. Diamond material is pressed into the flutes and through the aperture. Subsequent machining at the cutting end of the drill bit body exposes the sintered diamond forming a finished diamond cutting tip for the twist drill.

Abstract: A preform cutting element, for a rotary drill bit, includes a layer of polycrystalline diamond material having a front cutting face, a rear face and a peripheral surface, a cutting edge being provided by at least part of the junction between the front cutting face and the peripheral surface. The diamond layer is formed around its periphery, adjacent the cutting edge, with a row of spaced apertures. Each aperture is in the form of a bore, formed for example by a laser, which is inclined at 45.degree. to the cutting face and extends completely through the diamond layer from the cutting face to the peripheral surface thereof. The apertures serve to inhibit the propagation of spalling across the cutting face from the cutting edge.

Abstract: A drag bit mold fabricated from high temperature resisting material is machined to accept cylindrically shaped polycrystalline diamond cutters (PCD) having tungsten carbide bodies. Each of the multiple PCD matrix pockets in the mold is formed by two independent non-parallel end mill passes. The first end mill cut defines the PCD cutter position in the cutting face of the matrix diamond drag bit. The second end mill cut superimposed over the first end mill pocket creates a surrounding pocket which fills with powder metallurgy matrix material to provide support for the cylindrical cutter. The second end mill is only slightly larger than the first end mill to minimize the size of the insert securing fillet subsequently formed thus assuring that the fillet will not interfere with the depth of penetration of each of the PCD cutters.