Sumitomo Electric Industries, Limited

Sumitomo Electric Hardmetal Corp.

Katsuko Yamamoto

Hitoshi Sumiya

Keiko Arimoto

Kazuhiro Ikeda

Takeshi Sato

Yuh Ishida

Kensei Hamaki

Yutaka Kobayashi

Katsuyuki Tanaka

Minori Teramoto

Satoru Kukino

Naoji Fujimori

Katsumi Okamura

Hiromu Shiomi

Natsuo Tatsumi

Tomohiro Fukaya

Takashi Tsuno

Kazuo Nakamae

Yoshiaki Kumazawa

Takahisa Iguchi

Naohiro Toda

Teruhiro Enami

Mamoru Ono

Hiroyuki Murase

Toshimitsu Sakata

Provided is polycrystalline diamond having a diamond single phase as basic composition, in which the polycrystalline diamond includes a plurality of crystal grains and contains boron, hydrogen, oxygen, and the remainder including carbon and trace impurities; the boron is dispersed in the crystal grains at an atomic level, and greater than or equal to 90 atomic % of the boron is present in an isolated substitutional type; hydrogen and oxygen are present in an isolated substitutional type or an interstitial type in the crystal grains; each of the crystal grains has a grain size of less than or equal to 500 nm; and the polycrystalline diamond has a surface covered with a protective film.

Polycrystalline diamond and method for manufacturing same, scribe tool, scribe wheel, dresser, rotating tool, wire drawing die, cutting tool, electrode, and processing method using polycrystalline diamond

A diamond polycrystal includes diamond grains, the diamond polycrystal including a cubic diamond and a 6H type hexagonal diamond, wherein the cubic diamond and the 6H type hexagonal diamond exist in the same or different diamond grains, and a ratio Ab/Abis more than or equal to 0.4 and less than or equal to 1, Abrepresenting a maximum value of absorption in a range of more than or equal to 1200 cmand less than or equal to 1300 cmin an infrared absorption spectrum, Abrepresenting a maximum value of absorption in a range of more than or equal to 1900 cmand less than or equal to 2100 cm.

Diamond polycrystal, tool including diamond polycrystal, and method of producing diamond polycrystal

A diamond polycrystal is a diamond polycrystal basically composed of a diamond single phase, wherein the diamond polycrystal is composed of a plurality of diamond grains having an average grain size of less than or equal to 30 nm, and the diamond polycrystal has a carbon dangling bond density of more than or equal to 10 ppm.

Diamond polycrystal and method of producing the same

Provided is a synthetic single crystal diamond containing nitrogen atoms at a concentration of more than 600 ppm and 1500 ppm or less. The Raman shift &#x3bb;' (cm) of a peak in a primary Raman scattering spectrum of the synthetic single crystal diamond and the Raman shift &#x3bb; (cm) of a peak in a primary Raman scattering spectrum of a synthetic type IIa single crystal diamond containing nitrogen atoms at a content of 1 ppm or less satisfy the following expression (1):&#x3bb;&#x2032;&#x2212;&#x3bb;&#x2265;&#x2212;0.10&#x2003;&#x2003;(1).

Synthetic single crystal diamond

In a diamond polycrystal, a value of a ratio (d'/d) of d&#x2032; to d is less than or equal to 0.98 in a Vickers hardness test performed under a condition defined in JIS Z 2244:2009, where the d represents a length of a diagonal line of a first Vickers indentation formed in a surface of the diamond polycrystal when a Vickers indenter with a test load of 4.9 N is pressed onto the surface of the diamond polycrystal, and the d&#x2032; represents a length of a diagonal line of a second Vickers indentation remaining in the surface of the diamond polycrystal after releasing the test load.

Diamond polycrystal and tool including same

Provided is polycrystalline diamond having a diamond single phase as basic composition, in which the polycrystalline diamond includes a plurality of crystal grains and contains boron, at least either of nitrogen and silicon, and a remainder including carbon and trace impurities; the boron is dispersed in the crystal grains at an atomic level, and greater than or equal to 90 atomic % of the boron is present in an isolated substitutional type; the nitrogen and the silicon are present in an isolated substitutional type or an interstitial type in the crystal grains; each of the crystal grains has a grain size of less than or equal to 500 nm; and the polycrystalline diamond has a surface covered with a protective film.

Polycrystalline diamond and method for manufacturing same, scribe tool, scribe wheel, dresser, rotating tool, orifice for water jet, wire drawing die, cutting tool, electrode, and processing method using polycrystalline diamond

In a diamond polycrystal, a value of a ratio (a'/a) of a&#x2032; to a is less than or equal to 0.99 in a Knoop hardness test performed under a condition defined in JIS Z 2251:2009, where the a represents a length of a longer diagonal line of a first Knoop indentation formed in a surface of the diamond polycrystal when a Knoop indenter with a test load of 4.9 N is pressed onto the surface of the diamond polycrystal, and the a&#x2032; represents a length of a longer diagonal line of a second Knoop indentation remaining in the surface of the diamond polycrystal after releasing the test load.

An indenter is made of polycrystalline diamond and has a tip having a spherical surface with a radius of 10 to 2000 &#x3bc;m.

Indenter made of polycrystalline diamond, and method and apparatus using the same for evaluating crack initiation load

Nano polycrystalline diamond is composed of carbon, an element of different type which is an element other than carbon and is added to be dispersed in carbon at an atomic level, and an inevitable impurity. The polycrystalline diamond has a crystal grain size not greater than 500 nm. The polycrystalline diamond can be fabricated by subjecting graphite in which the element of different type which is an element other than carbon has been added to be dispersed in carbon at an atomic level to heat treatment within high-pressure press equipment.

Polycrystalline diamond and manufacturing method thereof, scribe tool, scribing wheel, dresser, rotating tool, orifice for water jet, wiredrawing die, cutting tool, and electron emission source

It is an object to provide a cubic boron nitride polycrystalline material excellent in toughness. A cubic boron nitride polycrystalline material containing fine cubic boron nitride which is granular, has a maximum grain size not greater than 100 nm, and has an average grain size not greater than 70 nm and at least one of plate-shaped cubic boron nitride in a form of a plate having an average major radius not smaller than 50 nm and not greater than 10000 nm and coarse cubic boron nitride which is granular, has a minimum grain size exceeding 100 nm, and has an average grain size not greater than 1000 nm is provided.

Cubic boron nitride polycrystalline material, cutting tool, wear resistant tool, grinding tool, and method of manufacturing cubic boron nitride polycrystalline material

The present diamond single crystal is a diamond single crystal containing nitrogen atoms, in which a concentration of the nitrogen atoms changes periodically along a crystal orientation of the diamond single crystal, and an arithmetic average value A, a maximum value A, and a minimum value Aof the distance of one period along the crystal orientation satisfy the relationship expressed by the following equation (I):()/1.25&#x2264;()&#x2264;()/0.75&#x2003;&#x2003;(I).

Diamond single crystal, tool, and method for producing diamond single crystal

A cubic boron nitride polycrystal includes cubic boron nitride, the cubic boron nitride having an average grain size of not more than 150 nm, the cubic boron nitride polycrystal having a crack generation load of not less than 25 N in a breaking strength test in which an R200 &#x3bc;m diamond indenter is used to apply a load at a rate of 100 N/min.

Cubic boron nitride polycrystal, cutting tool, wear-resistant tool, grinding tool, and method of producing cubic boron nitride polycrystal

A polycrystalline diamond body contains diamond particles, the diamond particles have a mean particle size of 50 nm or less, and a crack initiation load is 10 N or more as measured in a fracture strength test by pressing a diamond indenter D with a tip radius Dr of 50 &#x3bc;m against a surface of the polycrystalline diamond body at a load rate F of 100 N/min. Accordingly, a polycrystalline diamond body that is tough and has a small diamond particle size, a cutting tool, a wear-resistant tool, a grinding tool, and a method for producing the polycrystalline diamond body are provided.

Polycrystalline diamond body, cutting tool, wear-resistant tool, grinding tool, and method for producing polycrystalline diamond body

Nano polycrystalline diamond is composed of carbon and a plurality of impurities other than carbon. A concentration of each of the plurality of impurities is not higher than 0.01 mass %, and the nano polycrystalline diamond has a crystal grain size (a maximum length) not greater than 500 nm. The nano polycrystalline diamond can be fabricated by preparing graphite in which a concentration of an impurity is not higher than 0.01 mass % and converting graphite to diamond by applying an ultra-high pressure and a high temperature to graphite.

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Itami, Japan

Katsuko Yamamoto