Sumitomo Electric Industries, Limited

Kazuwo Tsuji

Shuichi Satoh

Katsuhito Yoshida

Takeru Nakashima

Nobuo Urakawa

Hitoshi Sumiya

Akito Yoshida

Junji Degawa

Yasushi Goda

Shuji Yazu

Katsuyuki Tanaka

Yoshiaki Kumazawa

Yasushi Gouda

Akifumi Fujioka

Shyuichi Satoh

Yosio Nisida

Keiichi Satoh

Yuzo Demizu

Masuo Nakagawa

Kiyofumi Muro

Moritami Okada

Process for the synthesis of diamond

A synthetic single crystal diamond for wire drawing die; the process of manufacturing it and a wire drawing die to utilize it are disclosed. At least one plane of the diamond for wire drawing die is a cleavage plane of (111) faces, and the drawing hole of wire drawing die lies vertical to the cleavage plane. The diamond for the wire drawing die is produced by providing a synthetic single crystal having 20-400 ppm nitrogen of Ib type diamond. A groove is made on the diamond surface parallel to (111) faces employing energy beams such as a laser beam, an ion beam and an electron beam. A wedge is struck into the groove to cleave the diamond, and a plate is obtained. Furthermore, the plate is divided into polyhedrons, employing either an energy beam or a blade. The cleavage plane of the polyhedron is almost parallel to the (111) faces of crystal, therefore the cleavage plane is used as the standard plane to build the drawing hole.

Synthetic single crystal diamond for wiring drawing dies and process for

A coated particle for synthesizing diamond includes: a single crystal of a fine diamond particle coated with at least one layer which contains at least one kind of solvent metal powder for synthesizing diamond and/or at least one kind of solvent metal powder with organic bonding material. Diamond abrasive particles for sawing are produced by a process which includes the steps of: coating fine diamond particles with at least one layer which contains at least one kind of solvent metal powder for synthesizing diamond and/or at least one kind of solvent metal powder with organic bonding material, filling a molding with the coated fine diamond particles, compacting, arranging a compact in a synthesizing vessel, heating the compact to a temperature above a solvent metal-graphite melting point under a pressure condition in which diamond is thermodynamically stable, and recovering the diamond abrasive particles.

Coated particles for synthesizing diamond and process for production of

Synthetic single crystal diamond for wire drawing dies

A method of synthesizing single diamond crystals using a carbon source containing at least 99.9 atomic % carbon-12. This is accomplished by graphitizing carbon-12 to form a highly crystalline material which can be used as a carbon source in an ultra high pressure creating apparatus to produce single diamond crystals by means of a temperature difference process.

Method of synthesizing single diamond crystals of high thermal

An infrared optical part comprised of a synthetic diamond single crystal, and a method of making the same. The infrared optical part is comprised of a synthetic diamond having a nitrogen content of not more than 5 ppm and a boron content of not more than 3 ppm, wherein the parallelism between its light incident and reflecting surfaces is not more than one minute. The infrared optical part is used as a window member in infrared spectral analysis. It is also used in the form of a pair of anvils for holding a sample therebetween in connection with the measurement of transmitted light that has passed through the sample after the sample is compressed. The part is also used in the form of an infrared ATR prism. The method involves the steps of abrading an infrared optical part having the above mentioned nitrogen and boron content by a grinder, measuring the parallelism between the light incident and reflecting surfaces of the part by laser light, and smoothing the grinding apparatus, whereby the parallelism is set to a level of not more than 2.91.times.10.sup.-4 radians.

Infrared optical element and method of making the same

An ohmic electrode for n-type cubic boron nitride is disclosed. The electrode is made of two thin films; and the first is at least one alloy material selected from a group consisting of Au-Si alloy, Au-Ge alloy and Au-Si-Ge alloy, and the second is at least one metallic material selected from a group consisting of Ni, Cr, Mo and Pt. A process for producing an ohmic electrode for n-type cBN is disclosed. The process is comprised of the following steps: providing a thin film of at least one alloy selected from Au-Si alloy, Au-Ge alloy and Au-Si-Ge alloy, the weight ratio of Si and Ge being from 0.1 to 35% by weight, on n-type cBN; providing a thin film of at least one metal selected from Ni, Cr, Mo and Pt on the thin alloy film; and subjecting the type cBN having the films thus provided to a heat-treatment process in an inert gas or in a vacuum at a temperature ranging from 350.degree. C. to 600.degree. C.

Process for manufacturing an ohmic electrode for n-type cubic boron

Diamond abrasive grains are produced by a process which comprises steps of: regularly arranging a plurality of diamond crystal seeds on a first metal solvent plate, stacking a second solvent metal plate on the first solvent metal plate so that the diamond crystal seeds are sandwiched by the first solvent metal plate and the second solvent metal plate, and stacking a graphite raw plate on the second solvent metal plate to construct a production system for the diamond abrasive grains, heating the system or heating the system with pressurizing to a temperature above a solvent metal-graphite eutectic point through a temperature and pressure condition in which diamond is thermodynamically unstable to establish a temperature and pressure condition in which diamond is thermodynamically unstable, and heating the system or heating the system with pressurizing to establish a temperature and pressure condition in which diamond is thermodynamically stable and maintaining said condition.

Process for production of diamond abrasive grains

Ohmic electrode for n-type cubic boron nitride and the process for

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.

Diamond tool

The present invention relates to hard abrasive particles comprising diamond nuclei and cubic boron nitride layers coated on said diamond nuclei and a method of producing the same. Diamond has the highest hardness but has not been used as grinding materials, abrasive compounds, cutting materials and the like of the iron group metals due to the reactivity thereof upon them at high temperatures. Accordingly, the present invention provides hard abrasive particles comprising diamond nuclei and single crystal or polycrystal cubic boron nitride layers coating a surface of said diamond nuclei, in which the diamond nuclei are connected with the cubic boron nitride layers among atoms thereof, as materials having the hardness equal to that of diamond and capable of using for the grinding, the abrasion and the like of the iron group metals and a method of producing the same.

Hard abrasive particle and method of producing same

A process for producing an ohmic electrode for p-type cBN is disclosed, which process comprises the steps of: providing a thin alloy film composed of Au and Be, the weight ratio of Be being from 0.1 to 15% by weight, on p-type cBN; providing a thin film of a metal selected from Ni, Cr, Mo, and Pt on the thin alloy film; and subjecting the p-type cBN having the films thus provided to a heat-treatment in an inert gas or in vacuo at a temperature of from 350.degree. C. to 600.degree. C.

Process for producing ohmic electrode for p-type cubic system boron

A composite material useful as a diode capable of operating at a high temperature, i.e., 500.degree. to 600.degree. C. or a semiconductor optical device capable of emitting ultraviolet rays is provided which comprises an electrically insulating single crystal diamond substrate and single crystal cubic boron nitride directly formed on one surface of the single crystal diamond in such a manner that the single crystal cubic boron nitride has the same plane index as the substrate.

Composite material

In a method of manufacturing a cubic boron nitride p-n junction body, cBN seed crystals (1) of a first conductivity type are made coexist with original BN (3) and a solvent (2) containing a doping material of a second conductivity type, to grow cBN of the second conductivity type from the seed crystals (1). The solvent (2) contains 0.1 to 5 percent by weight of the doping material. The seed crystals (1) are disposed one by one in a plurality of blocks of the solvent (2), which blocks are separated from each other, to be in contact with nothing but the solvent (2). Due to such disposal, no spontaneous nucleation is caused in portions other than the seed crystals (1). A large-grained cBN p-n junction body is obtained as the result.

Method of manufacturing cubic boron nitride p-n junction body

A hole-burning material which comprises at least one hole which is formed on a zero-phonone line and semi-permanently lasts without suffering from any change in the temperature range from 2 to 120 K. and which can be erased by irradiation of excited light having an energy larger than the zero-phonone line, in which the burnt holes have long life and deep depth and any single holes can be erased.

Growing community of inventors

Hyogo, Japan

Kazuwo Tsuji