Patent application number | Description | Published |
20100146865 | POLYCRYSTALLINE DIAMOND - An object is to provide polycrystalline diamond applicable to diverse applications; and a water jet orifice, a stylus for gravure printing, a scriber, a diamond cutting tool, and a scribing wheel that include such polycrystalline diamond. This object is achieved by polycrystalline diamond obtained by converting and sintering non-diamond carbon under an ultrahigh pressure and at a high temperature without addition of a sintering aid or a catalyst, wherein sintered diamond grains constituting the polycrystalline diamond have an average grain diameter of more than 50 nm and less than 2500 nm and a purity of 99% or more, and the diamond has a D90 grain diameter of (average grain diameter+average grain diameter×0.9) or less. | 06-17-2010 |
20120255236 | HIGH-HARDNESS CONDUCTIVE DIAMOND POLYCRYSTALLINE BODY AND METHOD OF PRODUCING THE SAME - A diamond sintered body conventionally used in a cutting tool or the like includes an iron group metal element as a sintering aid, and therefore has a problem in heat resistance. A diamond sintered body not including the iron group metal, on the other hand, does not have sufficient mechanical strength to be used as a tool material, and also does not have conductivity, which makes electrical discharge machining impossible, and thus processing thereof is difficult. A diamond polycrystalline body having high heat resistance and mechanical strength and having conductivity enabling electrical discharge machining is obtained by using only an amorphous or fine graphite-type carbon material as a starting material, adding boron thereto and concurrently performing conversion into diamond and sintering in an ultra-high pressure and temperature condition. | 10-11-2012 |
20120258035 | POLYCRYSTALLINE DIAMOND AND METHOD OF MANUFACTURING THE SAME - Polycrystalline diamond includes cubic diamond and hexagonal diamond, and a ratio of X-ray diffraction peak intensity of a (100) plane of the hexagonal diamond to X-ray diffraction peak intensity for a (111) plane of cubic diamond is not lower than 0.01%. In addition, a present method of manufacturing polycrystalline diamond includes the steps of preparing a non-diamond carbon material having a degree of graphitization not higher than 0.58 and directly converting the non-diamond carbon material to cubic diamond and hexagonal diamond and sintering the non-diamond carbon material, without adding any of a sintering agent and a binder, under pressure and temperature conditions at which diamond is thermodynamically stable. | 10-11-2012 |
20140026492 | CUTTING TOOL AND METHOD FOR PRODUCING SAME - The present invention provides a cutting tool that achieves cutting with high precision. The cutting tool of the present invention includes a cutting edge composed of a polycrystalline body including high-pressure-phase hard grains that contain one or more elements selected from the group consisting of boron, carbon, and nitrogen, the polycrystalline body being formed by subjecting a non-diamond carbon material and/or boron nitride, serving as a starting material, to direct conversion sintering under ultra-high pressure and high temperature without adding a sintering aid or a catalyst, in which letting the radius of curvature of the nose of the cutting edge of the cutting tool be R1, the sintered grains constituting the polycrystalline body have an average grain size of 1.2×R1 or less and a maximum grain size of 2×R1 or less. | 01-30-2014 |
20140170055 | POLYCRYSTALLINE DIAMOND AND MANUFACTURING METHOD THEREOF - 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. | 06-19-2014 |
20140186629 | 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 - 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. | 07-03-2014 |
20140219907 | SINGLE-CRYSTAL DIAMOND AND MANUFACTURING METHOD THEREOF - Single-crystal diamond is composed of carbon in which a concentration of a carbon isotope | 08-07-2014 |
20150176155 | DIAMOND SINGLE CRYSTAL, METHOD FOR PRODUCING THE SAME, AND SINGLE CRYSTAL DIAMOND TOOL - A method for producing a diamond single crystal includes implanting an ion other than carbon into a surface of a diamond single crystal seed substrate and thereby decreasing the transmittance of light having a wavelength of 800 nm, the surface having an off-angle of 7 degrees or less with respect to a {100} plane, and homoepitaxially growing a diamond single crystal on the ion-implanted surface of the seed substrate using a chemical vapor synthesis under synthesis conditions where the ratio N | 06-25-2015 |
20150176156 | SINGLE CRYSTAL DIAMOND AND DIAMOND TOOL - A single crystal diamond has a surface. In the single crystal diamond, a measurement region is defined in the surface, the measurement region includes a portion exhibiting a transmittance that is highest in the single crystal diamond and a portion exhibiting a transmittance that is lowest in the single crystal diamond, the measurement region has a plurality of square regions that are continuously arranged and each have a side having a length of 0.2 mm, and an average value of transmittances in each of the plurality of square regions is measured, wherein assuming that the average value of the transmittances in one square region is defined as T | 06-25-2015 |