The localized formation of graphene and diamond like structures on the surface of boron carbide is obtained due to exposure to high intensity laser illumination. The graphitization involves water vapor interacting with the laser illuminated surface of boron carbide and leaving behind excess carbon. The process can be done on the micrometer scale, allowing for a wide range of electronic applications. Raman is a powerful and convenient technique to routinely characterize and distinguish the composition of Boron Carbide (B.sub.4C), particularly since a wide variation in C content is possible in B.sub.4C. Graphitization of 1-3 μm icosahedral B.sub.4C powder is observed at ambient conditions under illumination by a 473 nm (2.62 eV) laser during micro-Raman measurements. The graphitization, with ˜12 nm grain size, is dependent on the illumination intensity. The process is attributed to the oxidation of B.sub.4C to B.sub.2O.sub.3 by water vapor in air, and subsequent evaporation, leaving behind excess carbon. The effectiveness of this process sheds light on amorphization pathways of B.sub.4C, a critical component of resilient mechanical composites, and also enables a means to thermally produce graphitic contacts on single crystal B.sub.4C for nanoelectronics.

Polycrystalline diamond cutters and methods of making thereof are described. The cutters include a substrate and a diamond body. The diamond body includes diamond particles spatially arranged according to a gradient of particle sizes. The methods include steps of suspending diamond particles in a liquid and allowing their sedimentation according to a gradient of particle sizes resulting in regions spatially arranged axially and/or radially in which a majority of diamond particles in one region have lower average sizes or average diameters comparative to a majority of diamond particles in a second region.

A method of making a ceramic composite component includes providing a fibrous preform or a plurality of fibers, providing a first plurality of particles, coating the first plurality of particles with a coating to produce a first plurality of coated particles, delivering the first plurality of coated particles to the fibrous preform or to an outer surface of the plurality of fibers, and converting the first plurality of coated particles into refractory compounds. The first plurality of particles or the coating comprises a refractory metal.

A system of infiltration for producing a ceramic matrix composite (CMC) is provided in which a slurry is applied to an outer surface of a porous preform. The porous preform includes a framework of ceramic fibers. The slurry may include a solvent and a particulate. The porous preform may be infiltrated with the slurry. The particulate in the slurry may include a plurality of coarse particles and a plurality of fine particles. The coarse particles may have a d50 factor of 10-20 microns. The fine particles may have a d50 factor of 0.5-3 microns. A ratio of coarse particles to fine particles in the slurry may be between 1.5:1 and 4:1, inclusively.

Provided is polycrystalline diamond having a diamond single phase as basic composition, in which the polycrystalline diamond includes a plurality of crystal grains and contains boron, hydrogen, oxygen, and the remainder including carbon and trace impurities; the boron is dispersed in the crystal grains at an atomic level, and greater than or equal to 90 atomic % of the boron is present in an isolated substitutional type; hydrogen and oxygen are present in an isolated substitutional type or an interstitial type in the crystal grains; each of the crystal grains has a grain size of less than or equal to 500 nm; and the polycrystalline diamond has a surface covered with a protective film.

Polycrystalline diamond includes a working surface and a peripheral surface extending around an outer periphery of the working surface. The polycrystalline diamond includes a first volume including an interstitial material and a second volume having a leached region that includes boron and titanium. A method of fabricating a polycrystalline diamond element includes positioning a first volume of diamond particles adjacent to a substrate, the first volume of diamond particles including a material that includes a group 13 element, and positioning a second volume of diamond particles adjacent to the first volume of diamond particles such that the first volume of diamond particles is disposed between the second volume of diamond particles and the substrate, the second volume of diamond particles having a lower concentration of material including the group 13 element than the first volume of diamond particles. Various other articles, assemblies, and methods are also disclosed.

The invention relates to SiC-bound diamond hard material particles, a porous component formed with SiC-bound diamond particles, methods for producing same and the use thereof. Diamond hard material particles and components have a composition of 30 vol. % to 65 vol. % diamond, 70 vol % to 35 vol. % SiC and 0 to 30 vol. % Si, and a component has a porosity in the range of 10% to 40%

A polycrystalline diamond and a polycrystalline diamond compact comprise nanostructured polycrystalline diamond particles (aggregates) and binder material. The nanostructured polycrystalline diamond particles (aggregates) are from starting raw materials of nanostructured polycrystalline diamond particles (aggregates) with a size of between 1 m-40 m. The polycrystalline diamond and the polycrystalline diamond compact may comprise micrometer-sized monocrystalline diamond particles. The binder material in the polycrystalline diamond or the polycrystalline diamond compact may be removed partially or completely by a leaching process. The method of making the polycrystalline diamond or the polycrystalline diamond compact comprises sintering diamond particles comprising the nanostructured polycrystalline diamond particles (aggregates) with a size of between 1 m-40 m under high temperature and high pressure in the presence of the binder material.

Provided are: an electroplated tool; a screw-shaped grindstone for grinding a gear; a method for manufacturing the electroplated tool; and a method for manufacturing the crew-shaped grindstone for grinding a gear. Said tool having a parent material, a plating layer that has a high-level portion and a low-level portion formed as strips on the parent material at different heights along the direction intersecting the processing direction, and electrodeposited abrasive grains exposed from the surface of the plating layer. The difference in height of the plating layer is preferably 50-100% of the average particle diameter of the abrasive grains, the width of the high-level portion of the plating layer is preferably 150-200% of the average particle diameter of the abrasive grains, and the width of the low-level portion of the plating layer is preferably 100-800% of the average particle diameter of the abrasive grains.

The present disclosure relates a spark plasma sintered polycrystalline diamond and methods of spark plasma sintering leached polycrystalline diamond. Spark plasma sintering produces plasma from a reactant gas found in the pores left by catalyst removal from leached polycrystalline diamond. The plasma forms diamond bonds and/or carbide structures in the pores, which may produce polycrystalline diamond that is has a higher impact strength than the leached polycrystalline diamond or other improved properties.