Sumitomo Electric Industries, Limited

Sumitomo Electric Hardmetal Corp.

National Institute of Advanced Industrial Science and Technology

Takeru Nakashima

Shuichi Satoh

Hitoshi Sumiya

Satoru Kukino

Shuji Yazu

Katsumi Okamura

Akihiko Ikegaya

Yasuyuki Kanada

Hideki Moriguchi

Tomohiro Fukaya

Kazuwo Tsuji

Yutaka Kobayashi

Kimihiro Ozaki

Minoru Yoshida

Yusuke Matsuda

Tadashi Yamaguchi

Shinichiro Yurugi

Tomoyuki Ishida

Keizo Kobayashi

Teruhiro Enami

Katsuyuki Kawate

Koji Sano

Moritami Okada

Kiyofumi Muro

Masuo Nakagawa

Yuzo Demizu

Yosio Nisida

Akio Fujimura

Mitsuo Nishimura

Takashi Hirao

A joined product has a cemented carbide sintered compact serving as a first material to be joined and a cBN sintered compact serving as a second material to be joined, wherein: the first material to be joined and the second material to be joined are joined together via a joining material disposed therebetween and containing titanium (Ti); and a titanium nitride (TiN) compound layer having a thickness of 10-300 nm is produced at an interface between the second material to be joined and the joining material.

Joined product

Various types of diamond tools are provided by utilizing the fact that a synthetic single crystal diamond for use in a tool having a nitrogen content of 3 ppm or less exhibits an enhanced hardness in a (100) plane in a &#x3c;111&#x3e; direction and simultaneously the reduction in defects. The above synthetic single crystal diamond is synthesized by the temperature difference method under an ultra high pressure at high temperature and contains, in its crystals, nickel introduced by atomic substitution or boron and nickel introduced by atomic substitution.

Diamond tool, synthetic single crystal diamond and method of synthesizing single crystal diamond, and diamond jewelry

To provide a diamond compact die semi-manufactured product and a diamond compact die that do not crack during die processing. A diamond compact die semi-manufactured product includes a diamond compact and a holding ring. The holding ring is a cylinder composed of a tungsten alloy, and the inner diameter thereof is tapered. The diamond compact is tapered so as to fit to the taper of the cylinder and the diamond compact is press-fitted to the holding ring. For lower cost production, the tapered face of the diamond compact is formed by electric spark machining. The tungsten alloy contains 90% to 97% by weight of tungsten and 3% to 10% by weight of nickel.

Material for diamond sintered body die and diamond sintered body die

An improved diamond sintered body having an excellent breakage resistance, corrosion resistance, heat resistance and wear resistance and capable of being sintered at a relatively low pressure and low temperature can be provided. The feature thereof consists in a diamond sintered body comprising 50 to 99.9 volume % of diamond and the balance of a binder phase consisting of a single or mixed phase of a compound (C) or composite (C') of at least one element (A) selected from the group consisting of rare earth elements, Group 3B, 4A, 4B and 6B elements of Periodic Table, iron group, Mn, V, alkali metals and alkaline earth metals with a phosphorus compound (B), or of the above described compound (C) or composite (C') with an oxide of (A).

Diamond sintered body and a process for the production of the same,

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

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.

Hole-burning material and production thereof

A method of manufacturing a diamond laser crystal having an excellent laser efficiency is performed by first, preparing a synthetic type Ib diamond containing at least 60 volume percent of a (111) plane growth sector (43) is prepared. This synthetic diamond is then thermally treated under high temperature/high pressure, so that type Ib nitrogen contained in the synthetic diamond is converted to type IaA nitrogen. Thereafter an electron beam is applied to the synthetic diamond in order to generate vacancies in the synthetic diamond. Finally annealing is performed on the synthetic diamond to form H3 centers by coupling the type IaA nitrogen atoms contained in the synthetic diamond, with the vacancies. According to this method, the H3 centers can be formed in the synthetic type Ib diamond at high concentration, while formation of NV centers which become an obstacle to laser action, can be suppressed.

Diamond laser crystal and method manufacturing the same

A diamond laser formed of a synthetic diamond provides a high output power and a variable wavelength in the near infrared region. The maximum value of the optical density of H2 centers in the direction of the pumping light is in the range of 0.01 to 4. Laser action is caused in the range of 1000 to 1400 nm by an external pumping light at 650 to 950 nm. Such a diamond laser is produced by preparing a synthetic Ib type diamond having a nitrogen concentration within the range of 1.times.10.sup.17 to 8.5 10.sup.19 atoms/cm.sup.3, subjecting this synthetic diamond to an electron irradiation with a dose of not less than 5.times.10.sup.17 electrons/cm.sup.2, and heat-treating the synthetic diamond in a vacuum of not more than 1 Torr or in an inert gas atmosphere and at a temperature within the range of 1400.degree. to 1850.degree. C. If the threshold value of the pumping light intensity necessary for causing laser action is Ith then, to make the pumping light intensity I greater than Ith throughout the laser crystal, it is important, that the maximum value of the optical density of H2 is within the range between 0.01 and 4.

Diamond laser, method for producing the same, and method for activating

Growing community of inventors

Itami, Japan

Takeru Nakashima