Abstract: A superabrasive tool such as a superabrasive grindstone (101; 102), a superabrasive dresser (103; 104; 105) or a superabrasive lap surface plate (106) includes a base (20) of steel and a superabrasive layer (10) formed on the base (20). The superabrasive layer (10) includes superabrasive grains (11) consisting of diamond grains, cubic boron nitride grains or the like and a holding layer consisting of a nickel plating layer (16) and a bond layer (17), or a brazing filler metal layer (18), holding the superabrasive grains (11) and fixing the same onto the base (20). Grooves (12) or holes (14) are formed on flat surfaces (19) of the superabrasive grains (11) exposed from the holding layer (16, 17; 18). The holding layer (16, 17; 18) holding and fixing the superabrasive grains (11) so that the surfaces of the grains are partially exposed is formed on the base (20).

Abstract: A core bit includes a tube (2) having an opening end surface (21) in the axial direction and a plurality of tips (3) fixed to the opening end surface (21) of the tube (2). Each of the tips (3) includes an abrasive grain layer (31) that contains diamond abrasive grains and a binder for bonding the diamond abrasive grains to each other. The diamond abrasive grains contain not more than 0.03 weight % of inclusions. The inclusions contain iron and nickel as main components. The binder contains at least 0.1 weight % and not more than 2.0 weight % of graphite. The core bit has a short perforation time, i.e., a high cutting speed, excellent sharpness, excellent durability, and a long life. The core bit is suitable for boring a concrete structure.

Abstract: The present invention provides a wire saw for use in cutting works of electronics materials or optical materials and a method for manufacturing the same, said wire saw having the following characteristic features. Namely, onto a high-strength core wire 2, abrasive grains 3 having a grain size not smaller than two-thirds the thickness of a layer of resin bond 4 on said core wire 2 but not exceeding a half the diameter of said core wire are fixed with said resin bond, said resin bond containing a filler having a grain size smaller than two-thirds the thickness of said resin bond layer. The thus structured and arranged wire saw has an improved efficiency and precision in cutting. The wire saw can be manufactured readily by using an enamelling oven.

Abstract: The present invention provides a superhard film-coated member having a diamond or diamond-like carbon film strongly bonded to a cemented carbide substrate and a method of manufacturing such a member. The cemented carbide substrate is subjected to heat treatment to cause the bonding metal in a region of the substrate near to its surface to migrate to the surface so as to form hemispherical deposits thereon. The deposits are left undisturbed or a part or all thereof are removed, and subsequently diamond and/or diamond-like carbon is grown on the substrate surface by a chemical vapor deposition process. The deposits formed on the substrate surface have the effect of significantly improving the bonding strength between the superhard films and the cemented carbide substrate to allow formation of thicker film coatings.

Abstract: A method is provided for efficiently producing an entirely quality-controlled CVD diamond. A CVD process is interrupted at an early stage and the deposit is taken out of the reaction chamber, before a significant mass is accumulated, and is inspected by means of cathodoluminescence. The spectrum are compared with a given reference in terms of peak position, half width and 20%-value width in coordination. The observed deviation allows to determine whether to maintain or alter the settings.A diamond substance of acceptable quality which is properly specified in terms of the CL parameters is also provided.

Abstract: A blade comprises a disc-shaped substrate having a major surface and an outer peripheral edge portion encircling the major surface, and an abrasive grain layer mounted on the outer peripheral edge portion of the substrate. The substrate includes a first disc having a major surface, and a second disc having a major surface which is superposed on that of the first disc. The major surface of the second disc is separated from that of the first disc, thereby defining a clearance between the major surfaces of the first and second discs and correspondingly forming a convex surface region on the outside surface of the substrate. The peripheral portion of the convex surface region is provided with a contact portion where the major surfaces of the first and second discs are slidably in contact with each other.

Abstract: Making a diamond substance exhibiting a cathodoluminescence spectrum with the peak at a photon energy greater than 2.8 eV (electron volt), the half-value and 20%-value width not exceeding 0.5 eV and 0.8 eV, respectively, comprising: providing a substrate in a closed chamber, introducing a matrix gas comprising H.sub.2 and one selected from hydrocarbon and CO to said chamber, exciting the gas to create a plasma while heating said substrate to a temperature of at least 700.degree. C. and, thus, causing deposition and growth of diamond substance which is crystallographically diamond, controlling parameters of the deposition by means of the cathodoluminescence record and recovering the diamond substance from the chamber.

Abstract: A rotary blade has a rotary substrate with chips disposed about the outer edge of the substrate. The substrate further has two sets of semicircular slits. The first set of semicircular slits is disposed annularly about the rotary substrate on a circle coaxial with the center of rotation of the rotary blade. The semicircular slits open toward the center of rotation. The second set of semicircular slits are disposed on a circle inside of the circle of first slits. These slits open outwardly, thus blocking, at least partially, the first semicircular slits from the center of rotation. A filler material is filled into the semicircular slits, the slits thus providing a vibration damping effect. The chips may be attached to the outer edge of the rotary substrate by concave profiled cassette stands.

Abstract: A plurality of abrasive sleeves (3) surround a wire rope (2) and are spaced at predetermined intervals longitudinally of the wire rope. An elastic material (4) of rubber such as natural rubber is formed between the abrasive sleeves in such a manner as to surround the wire rope. A rubber/metal bonding agent (7) such as chlorinated rubber type bonding agent is used to effect vulcanization bonding between the opposite end surfaces of each abrasive sleeve and the elastic material and between the wire rope and the elastic material. The ends (19) of the wire rope are connected together by a combination of end connecting members (5, 6a) provided with male threads (17, 17a) and fixed to the ends of the wire rope and on internally threaded connecting sleeve (30), whereby a closed loop is formed.

Abstract: An improved wire saw having a wire rope, a resilient layer covering the outer periphery of the wire rope, and a plurality of sleeves mounted on the wire rope through the resilient layer at spacings, the sleeves having an abrasive layer on their outer periphery. The resilient layer has a smaller outer diameter at portions between the sleeves than over and adjacent to the sleeves. The sleeves or the resilient layer is provided with an engaging portion to axially extend to prevent one of them from turning with respect to the other.

Abstract: Method for welding cutter-segments characterized by focusing an electron beam or a laser beam on the boundary between a carbon-steel core body (7) and segments (1). Each segment is formed by a Co (cobalt) powder compact, containing diamond or CBN grit, which has been sintered to nearly 100% apparent density. The boundary may or may not have Ni (nickel)-filler. In cases of bond materials other than Co, the segment (1) has a structure of double layers (4, 5), one layer of which is composed of a powder compact, containing diamond or CBN grit, which has been sintered to nearly 100% apparent density, and the other layer (5) of which is composed of a sintered Co powder compact without any grit. The carbon-steel core body (7) welded by the above-mentioned method is thereafter tempered at 350.degree.-450.degree. C. if necessary. A steel core having no slot at its periphery may be used as the core body.