A method and apparatus for preparing boron nitride nanotubes (BNNTs) according to an embodiment may ensure mass-production, may increase yield by reducing a production time, and may prepare BNNTs with high purity.

A device for measuring a light radiation pressure is provided which includes a torsion balance, a laser, a convex lens, and a line array detector. The laser is configured to emit a first laser beam. The convex lens is located on an optical path of the first laser beam and configured to focus the first laser beam to a surface of the reflector. The line array detector is configured to detect a reflected first laser beam reflected by the reflector. The disclosure also provides a method for measuring the light radiation pressure using the device.

Provided is a method for producing, with a small amount of lithium, a hexagonal boron nitride powder containing thick hexagonal boron nitride particles. A method for producing a hexagonal boron nitride powder, including the steps of: preparing a mixed powder which contains an organic compound containing nitrogen atoms, a boron source which contains boron atoms whose molar ratio with respect to the nitrogen atoms is adjusted to be 0.26 or more and 0.67 or less, and an alkali metal in which lithium atoms are adjusted to be in a range of 30 mol % or more and less than 100 mol %, the alkali metal being present such that a molar ratio of the boron atoms with respect to alkali metal atoms contained in the alkali metal is 0.75 or more and 3.35 or less; and heating the mixed powder at a maximum temperature of 1200° C. or higher and 1500° C. or lower.

Polycrystalline cubic boron nitride compact include a body having sintered microcrystalline cubic boron nitride in a matrix of binder material. The microcrystalline cubic boron nitride particles have a size ranging from 2 microns to 50 microns. The particles of microcrystalline cubic boron nitride include a plurality of sub-grains, each sub-grain having a size ranging from 0.1 micron to 2 microns. The compacts are manufactured in a high pressure—high temperature (HPHT) sintering process. The compacts exhibit intergranular defect formation following introduction of wear. The sub-grains promote crack propagation based on micro-chipping rather than on a cleavage mechanism and, in sintered bodies, cracks propagate intergranularly rather than intragranularly, resulting in increased toughness and improved wear characteristics as compared to monocrystalline cubic boron nitride. The compacts are suitable for use as abrasive tools.

Polycrystalline cubic boron nitride compact include a body having sintered microcrystalline cubic boron nitride in a matrix of binder material. The microcrystalline cubic boron nitride particles have a size ranging from 2 microns to 50 microns. The particles of microcrystalline cubic boron nitride include a plurality of sub-grains, each sub-grain having a size ranging from 0.1 micron to 2 microns. The compacts are manufactured in a high pressure—high temperature (HPHT) sintering process. The compacts exhibit intergranular defect formation following introduction of wear. The sub-grains promote crack propagation based on micro-chipping rather than on a cleavage mechanism and, in sintered bodies, cracks propagate intergranularly rather than intragranularly, resulting in increased toughness and improved wear characteristics as compared to monocrystalline cubic boron nitride. The compacts are suitable for use as abrasive tools.

Disclosed are methods for forming boron nitride-containing aggregates that exhibit improved wear by attrition, and resulting filled polymers that exhibit significantly improved thermal conductivity. The boron nitride-containing aggregates are prepared according to a method that includes wet granulating boron nitride powder with a granulation solution to form wet boron nitride-containing granules; and drying the wet boron nitride-containing granules to cause evaporation of solvent in the granulation solution, thereby forming boron nitride-containing granules. Sintering achieves the desired boron nitride-containing aggregates.

The present disclosure provides a method for preparing a multi-layer hexagonal boron nitride film, including: preparing a substrate; preparing a boron-containing solid catalyst, and disposing the boron-containing solid catalyst on the substrate; annealing the boron-containing solid catalyst to melt the boron-containing solid catalyst; feeding a nitrogen-containing gas and a protecting gas to an atmosphere in which the melted boron-containing solid catalyst resides, the nitrogen-containing gas reacts with the boron-containing solid catalyst to form the multi-layer hexagonal boron nitride film on a surface of the substrate. The method for preparing a multi-layer hexagonal boron nitride film can prepare a hexagonal boron nitride film having a lateral size in the order of inches and a thickness from several nanometers to several hundred nanometers on the surface of the substrate, providing a favorable basis for the application of hexagonal boron nitride in the field of two-dimensional material devices.

The present disclosure provides a method for preparing a multi-layer hexagonal boron nitride film, including: preparing a substrate; preparing a boron-containing solid catalyst, and disposing the boron-containing solid catalyst on the substrate; annealing the boron-containing solid catalyst to melt the boron-containing solid catalyst; feeding a nitrogen-containing gas and a protecting gas to an atmosphere in which the melted boron-containing solid catalyst resides, the nitrogen-containing gas reacts with the boron-containing solid catalyst to form the multi-layer hexagonal boron nitride film on a surface of the substrate. The method for preparing a multi-layer hexagonal boron nitride film can prepare a hexagonal boron nitride film having a lateral size in the order of inches and a thickness from several nanometers to several hundred nanometers on the surface of the substrate, providing a favorable basis for the application of hexagonal boron nitride in the field of two-dimensional material devices.

Aligned high quality boron nitride nanotubes (BNNTs) can be incorporated into groups and bundles and placed in electronic and electrical components (ECs) to enhance the heat removal and diminish the heat production. High quality BNNTs are excellent conductors of heat at the nano scale. High quality BNNTs are electrically insulating and can reduce dielectric heating. The BNNTs composite well with a broad range of ceramics, metals, polymers, epoxies and thermal greases thereby providing great flexibility in the design of ECs with improved thermal management. Controlling the alignment of the BNNTs both with respect to each other and the surfaces and layers of the ECs provides the preferred embodiments for ECs.

Aligned high quality boron nitride nanotubes (BNNTs) can be incorporated into groups and bundles and placed in electronic and electrical components (ECs) to enhance the heat removal and diminish the heat production. High quality BNNTs are excellent conductors of heat at the nano scale. High quality BNNTs are electrically insulating and can reduce dielectric heating. The BNNTs composite well with a broad range of ceramics, metals, polymers, epoxies and thermal greases thereby providing great flexibility in the design of ECs with improved thermal management. Controlling the alignment of the BNNTs both with respect to each other and the surfaces and layers of the ECs provides the preferred embodiments for ECs.