A cubic boron nitride sintered material tool contains a plurality of cBN grains. cBN grains located on a surface of the cutting edge contain a cubic boron nitride phase, and a hexagonal boron nitride phase. When a ratio I.sub.π*/I.sub.σ* between an intensity of a π* peak derived from a π bond of hBN in the hexagonal boron nitride phase and an intensity of a σ* peak derived from a σ bond of hBN in the hexagonal boron nitride phase and a σ bond of cBN in the cubic boron nitride phase is determined by measuring an energy loss associated with excitation of K-shell electrons of boron, the ratio I.sub.π*/I.sub.σ* of the cBN grain on the surface of the cutting edge is 0.1 to 2, and the ratio I.sub.π*/I.sub.σ* of the cBN grain at a depth position of 5 μm from the surface of the cutting edge is 0.001 to 0.1.

A member for a plasma processing device of the present disclosure is a member for a plasma processing device made of ceramics and having a shape of a cylindrical body with a through hole in an axial direction. The ceramics is mainly composed of aluminum oxide, and has a plurality of crystal grains and a grain boundary phase that is present between the crystal grains. An inner peripheral surface of the cylindrical body has an arithmetic average roughness Ra of 1 μm or more and 3 μm or less, and an arithmetic height Rmax of 30 μm or more and 130 μm or less.

A member for a plasma processing device of the present disclosure is a member for a plasma processing device made of ceramics and having a shape of a cylindrical body with a through hole in an axial direction. The ceramics is mainly composed of aluminum oxide, and has a plurality of crystal grains and a grain boundary phase that is present between the crystal grains. An inner peripheral surface of the cylindrical body has an arithmetic average roughness Ra of 1 μm or more and 3 μm or less, and an arithmetic height Rmax of 30 μm or more and 130 μm or less.

A problem to be solved is to provide a method for processing zirconia without producing a monoclinic crystal. The solution is a method for processing zirconia, including the step of irradiating the zirconia with a laser with a pulse duration of 10.sup.−12 seconds to 10.sup.−15 seconds at an intensity of 10.sup.13 to 10.sup.15 W/cm.sup.2.

Systems for and methods for improving mechanical properties of ceramic material are provided. The system comprises a heat source for heating the ceramic material to a temperature greater than a brittle-to-ductile transition temperature of the ceramic material; a probe for mounting the ceramic material and configured to extend the ceramic material into the heat source; a plasma-confining medium and a sacrificial layer disposed between the ceramic material and the plasma-confining medium; and an energy pulse generator such as a laser pulse generator. The sacrificial layer is utilized to form plasma between the ceramic material and the plasma-confining medium. The method comprises heating ceramic material to a temperature greater than a brittle-to-ductile transition temperature of the ceramic material and subjecting the ceramic material to energy pulses via a sacrificial layer and a plasma-confining medium whereby a plasma of the sacrificial coating forms between the ceramic material and a plasma-confining medium.

A method of inhibiting an irregular aggregation of a nanosized powder includes (A) providing a nanosized ceramic powder to perform thereon a thermal analysis and thereby attain an endothermic peak temperature; (B) performing an impurity-removal heat treatment on the nanosized ceramic powder at a temperature higher than the endothermic peak temperature; (C) switching the nanosized ceramic powder from a temperature environment of the impurity-removal heat treatment to an environment of a temperature higher than a phase change temperature of the nanosized ceramic powder, followed by performing a calcination heat treatment on the nanosized ceramic powder in the environment of the temperature higher than the phase change temperature of the nanosized ceramic powder, wherein the nanosized ceramic powder skips the temperature environment between impurity-removal heat treatment and calcination heat treatment to shun generating a vermicular structure, avoid crystalline irregularity and abnormal growth, reduce particle aggregation, and achieve satisfactory distribution.

A method of inhibiting an irregular aggregation of a nanosized powder includes (A) providing a nanosized ceramic powder to perform thereon a thermal analysis and thereby attain an endothermic peak temperature; (B) performing an impurity-removal heat treatment on the nanosized ceramic powder at a temperature higher than the endothermic peak temperature; (C) switching the nanosized ceramic powder from a temperature environment of the impurity-removal heat treatment to an environment of a temperature higher than a phase change temperature of the nanosized ceramic powder, followed by performing a calcination heat treatment on the nanosized ceramic powder in the environment of the temperature higher than the phase change temperature of the nanosized ceramic powder, wherein the nanosized ceramic powder skips the temperature environment between impurity-removal heat treatment and calcination heat treatment to shun generating a vermicular structure, avoid crystalline irregularity and abnormal growth, reduce particle aggregation, and achieve satisfactory distribution.

A method for forming an ultra-high temperature (UHT) composite structure includes dispensing a polymeric precursor with a spinneret biased at a first DC voltage; forming a plurality of nanofibers from the polymeric precursor; receiving the plurality of nanofibers with a collector biased at a second DC voltage different than the first DC voltage; and changing a direction of movement of the plurality of nanofibers between the spinneret and the collector with a plurality of magnets having a magnetic field by adjusting the magnetic field.

The purpose of the present invention is to achieve an in-situ observation of structural change in a shear field of slurry, i.e. an evaluation of a rheology property of slurry containing raw materials of a ceramic as a fluid sample, together with an in-situ observation of internal structure of the fluid sample in an evaluation process, and a clarification of internal structural change. An observation of an internal structure of a fluid sample 1 in an evaluation process of a rheology property by a rheometer 10 is achieved by generating an optical coherence tomographic image by performing an optical coherence tomography by irradiating a light in infrared region from outside of the rheometer 10 to the fluid sample 1, by inclining an optical axis of light in infrared region irradiating the fluid sample 1 for a predetermined angle within an angular range of 1 to 10 degrees with respect to a normal direction of an observation surface 1A of the fluid sample 1 by the optical coherence tomography imaging device 20, together with an evaluation of a rheology property of the fluid sample 1 containing components different in a refractive index by the rheometer 10.

The purpose of the present invention is to achieve an in-situ observation of structural change in a shear field of slurry, i.e. an evaluation of a rheology property of slurry containing raw materials of a ceramic as a fluid sample, together with an in-situ observation of internal structure of the fluid sample in an evaluation process, and a clarification of internal structural change. An observation of an internal structure of a fluid sample 1 in an evaluation process of a rheology property by a rheometer 10 is achieved by generating an optical coherence tomographic image by performing an optical coherence tomography by irradiating a light in infrared region from outside of the rheometer 10 to the fluid sample 1, by inclining an optical axis of light in infrared region irradiating the fluid sample 1 for a predetermined angle within an angular range of 1 to 10 degrees with respect to a normal direction of an observation surface 1A of the fluid sample 1 by the optical coherence tomography imaging device 20, together with an evaluation of a rheology property of the fluid sample 1 containing components different in a refractive index by the rheometer 10.