Patent classifications
C04B2235/767
SiAlON ceramics and a method of preparation thereof
A Ca—SiAlON ceramic with enhanced mechanical properties and a method employing micron-sized and submicron precursors to form the Ca—SiAlON ceramic. The Ca—SiAlON ceramic comprises not more than 42 wt % silicon, relative to the total weight of the Ca—SiAlON ceramic. The method employs submicron particles and also allows for substituting a portion of aluminum nitride with aluminum to form the Ca—SiAlON ceramic with enhanced mechanical properties.
POLYCRYSTALLINE CUBIC BORON NITRIDE AND METHOD FOR MANUFACTURING THE SAME
There is provided a polycrystalline cubic boron nitride containing a cubic boron nitride at a content greater than or equal to 98.5% by volume, the polycrystalline cubic boron nitride having a dislocation density less than or equal to 8×10.sup.15/m.sup.2.
Magnetic materials with ultrahigh resistivity intergrain nanoparticles
A composite magnetic material has a plurality of grains having a magnetic ferrite phase, grain boundaries surrounding the grains, and a plurality of nanoparticles disposed at the grain boundaries. The nanoparticles of the composite material are both magnetic and electrically insulating, having a magnetic flux density of greater than about 100 mT and an electrical resistivity of at least about 10.sup.8 Ohm-cm. Also provided is a method of making the composite material. The material is useful for making inductor cores of electronic devices.
Polycrystalline cubic boron nitride and method for manufacturing the same
A polycrystalline cubic boron nitride comprising 98.5% by volume or more of cubic boron nitride, wherein the cubic boron nitride has a dislocation density of more than 8×10.sup.15/m.sup.2, the polycrystalline cubic boron nitride comprises a plurality of crystal grains, and the plurality of crystal grains have a median diameter d50 of an equivalent circle diameter of 0.1 μm or more and 0.5 μm or less.
Ferrite sintered magnet, motor and generator
A ferrite sintered magnet contains a main phase formed of ferrite having a hexagonal magnetoplumbite type crystalline structure; a first subphase containing La, Ca, and Fe, in which an atomic ratio of La is higher than that of the main phase, and the atomic ratio of La is higher than an atomic ratio of Ca; and a second subphase containing La, Ca, Si, B, and Fe, in which an atomic ratio of Ca is higher than an atomic ratio of La, an atomic ratio of B is higher than an atomic ratio of Fe, and the atomic ratio of Fe is lower than that of the main phase. An area ratio of the second subphase on a cross-sectional surface of the ferrite sintered magnet is greater than or equal to 1%.
DRILLING TOOLS MADE OF WURTZITE BORON NITRIDE (W-BN)
Systems and methods include a computer-implemented method can be used to make drilling tools from new wurtzite boron nitride (w-BN) superhard material. An ultra-high-pressure, high-temperature operation is performed on pure w-BN powder to synthesize w-BN and cubic boron nitride (c-BN) compact having a first size greater than particles of the pure w-BN powder. The ultra-high-pressure, high-temperature operation includes pressurizing the w-BN powder to a pressure of approximately 20 Gigapascal, heating the w-BN powder at a heating rate of 100° C./minute and cooling the w-BN powder at a cooling rate of 50° C./minute. The compact is cut to a second size smaller than the first size using laser cutting tools. The cut compact is bonded metallurgically, mechanically, or both metallurgically and mechanically onto a tool substrate to form the drilling tool.
METHOD OF PREPARING A SOLID SOLUTION CERAMIC MATERIAL HAVING INCREASED ELECTROMECHANICAL STRAIN, AND CERAMIC MATERIALS OBTAINABLE THEREFROM
The present invention relates to a method of preparing a solid solution ceramic material having increased electromechanical strain, as well as ceramic materials obtainable therefrom and uses thereof. In one aspect, the present invention provides a method A method of increasing electromechanical strain in a solid solution ceramic material which exhibits an electric field induced strain derived from a reversible transition from a non-polar state to a polar state; i) determining a molar ratio of at least one polar perovskite compound having a polar crystallographic point group to at least one non-polar perovskite compound having a non-polar crystallographic point group which, when combined to form a solid solution, forms a ceramic material with a major portion of a non-polar state; ii) determining the maximum polarization, P.sub.max, remanent polarisation, P.sub.r, and the difference, P.sub.max−P.sub.r, for the solid solution formed in step i); and either: iii)a) modifying the molar ratio determined in step i) to form a different solid solution of the same perovskite compounds which exhibits an electric field induced strain and which has a greater difference, P.sub.max−P.sub.r, between maximum polarization, P.sub.max, and remanent polarisation, P.sub.r, than for the solid solution from step i), or; iii)b) adjusting the processing conditions used for preparing the solid solution formed in step i) to increase the difference, P.sub.max−P.sub.r, in maximum polarization, P.sub.max, and remanent polarisation, P.sub.r, of the solid solution.
COMPOSITE, METHOD FOR PRODUCING COMPOSITE, LAMINATE, AND METHOD FOR PRODUCING LAMINATE
The present disclosure provides a composite including a nitride sintered body having a porous structure and a semi-cured product of a heat-curable composition impregnated into the nitride sintered body, wherein a dielectric breakdown voltage obtainable after disposing the composite between adherends, heating and pressurizing the composite for 5 minutes under the conditions of 200° C. and 10 MPa, and further heating the composite for 2 hours under the conditions of 200° C. and atmospheric pressure, is greater than 5 kV.
SILICON NITRIDE SINTERED BODY, METHOD FOR PRODUCING SAME, MULTILAYER BODY AND POWER MODULE
Provided is a method for producing a silicon nitride sintered body including: a step of molding and firing a raw material powder containing silicon nitride, in which an α-conversion rate of the silicon nitride contained in the raw material powder is less than or equal to 30 mass %. A thermal conductivity (at 20° C.) of the silicon nitride sintered body exceeds 100 W/m.Math.K and a fracture toughness (K.sub.IC) is greater than or equal to 7.4 MPa.Math.m.sup.1/2.
System and methods for fabricating boron nitride nanostructures
This disclosure provides systems, methods, and apparatus related to boron nitride nanomaterials. In one aspect, a method includes generating a directed flow of plasma. A boron-containing species is introduced to the directed flow of the plasma. Boron nitride nanostructures are formed in a chamber. In another aspect, a method includes generating a directed flow of plasma using nitrogen gas. A boron-containing species is introduced to the directed flow of the plasma. The boron-containing species can consist of boron powder, boron nitride powder, and/or boron oxide powder. Boron nitride nanostructures are formed in a chamber, with a pressure in the chamber being about 3 atmospheres or greater.