Patent classifications
C04B2235/46
Ceramic matrix composite manufacturing
A method of manufacturing a ceramic matrix composite component may include introducing a gaseous precursor into an inlet portion of a chamber that houses a porous preform and introducing a gaseous mitigation agent into an outlet portion of the chamber that is downstream of the inlet portion of the chamber. The gaseous precursor may include methyltrichlorosilane (MTS) and the gaseous mitigation agent may include hydrogen gas. The introduction of the gaseous precursor may result in densification of the porous preform(s) and the introduction of the gaseous mitigation agent may shift the reaction equilibrium to disfavor the formation of harmful and/or pyrophoric byproduct deposits, which can accumulate in an exhaust conduit 340 of the system.
BORON NITRIDE NANOTUBE (BNNT)-NANOPARTICLE COMPOSITES, METHODS FOR THE PREPARATION THEREOF AND THEIR MACROSCOPIC ASSEMBLIES
The present application relates to boron nitride nanotube (BNNT)-nanoparticle composites, to methods of preparing such composites and their use, for example, in metal/ceramic matrix composites and/or macroscopic assemblies. For example, the methods comprise subjecting a source of hydrogen, a source of boron, a source of nitrogen and a nanoparticle precursor to a stable induction thermal plasma and cooling the reaction mixture to obtain the composite.
Electrorefining of magnesium from scrap metal aluminum or magnesium alloys
The invention comprises methods and apparatuses for the electrorefining of Mg from Al or Mg alloy scrap. The invention utilizes the density and charge features of Mg present in a melted alloy to continuously extract Mg and Mg alloys from a melted Al alloy feed.
SEMICONDUCTOR DEVICES AND METHOD OF MANUFACTURING THE SAME
A method of manufacturing a semiconductor device includes forming a preliminary lower electrode layer on a substrate, the preliminary lower electrode layer including a niobium oxide; converting at least a portion of the preliminary lower electrode layer to a first lower electrode layer comprising a niobium nitride by performing a nitridation process on the preliminary lower electrode layer; forming a dielectric layer on the first lower electrode layer; and forming an upper electrode on the dielectric layer.
SYSTEMS AND METHODS FOR CARBON STRUCTURES INCORPORATING SILICON CARBIDE
A method of treating a carbon/carbon composite is provided. The method may include infiltrating a carbonized fibrous structure with hydrocarbon gas to form a densified fibrous structure. The method may include treating the densified fibrous structure with heat at a first temperature range from about 1600 to about 2400 C. to form a heat treated densified fibrous structure. The method may include infiltrating the heat treated densified fibrous structure with silicon to form a silicon carbide infiltrated fibrous structure.
PIEZOELECTRIC FILM, METHOD OF PRODUCING PIEZOELECTRIC FILM, PIEZOELECTRIC ELEMENT, AND PIEZOELECTRIC DEVICE
A piezoelectric film contains a piezoelectric material having a wurtzite-type crystal structure as a main component, and an additive element containing Kr, wherein the piezoelectric material contains a component selected from the group consisting of Zn, Al, Ga, Cd, and Si, as an electropositive element, and wherein a ratio of a content of Kr element to a content of contained elements in the piezoelectric material is in a range from 0.01 atm % to 0.05 atm %.
Method and assembly for infiltration and rapid phase deposition of porous components
A chemical vapor infiltration (CVI) method for densifying at least one porous component includes placing the at least one porous component inside a crucible, bringing temperature inside the crucible to a value adapted to densify the porous component to transform it into a densified component, bringing pressure inside the crucible between 0.1 KPa and 25 KPa, once operational temperature and pressure are reached, flowing gas inside the crucible, gas being suitable for densifying the porous component to transform it into a densified component, and keeping an oxidizing environment outside the crucible, the external environment lapping against the crucible. The crucible is provided of at least one material having thermal conductivity greater than 30 W/mK from room temperature to at least 1000? C. selected from: sintered silicon carbide (SiC), silicon-infiltrated silicon carbide (SiSiC), sintered boron carbide (B4C), silicon-infiltrated boron carbide (SiB4C), sintered zirconium carbide (ZrC), silicon-infiltrated zirconium carbide (SiZrC), a combination of silicon carbide (SiC), boron carbide (B4C) and sintered and/or silicon-infiltrated zirconium carbide (ZrC).
METAL NITRIDES AND/OR METAL CARBIDES WITH NANOCRYSTALLINE GRAIN STRUCTURE
Disclosed is a composition having nanoparticles or particles of a refractory metal, a refractory metal hydride, a refractory metal carbide, a refractory metal nitride, or a refractory metal boride, an organic compound consisting of carbon and hydrogen, and a nitrogenous compound consisting of carbon, nitrogen, and hydrogen. The composition, optionally containing the nitrogenous compound, is milled, cured to form a thermoset, compacted into a geometric shape, and heated in a nitrogen atmosphere at a temperature that forms a nanoparticle composition comprising nanoparticles of metal nitride and optionally metal carbide. The nanoparticles have a uniform distribution of the nitride or carbide.
Mitigating Pyrophoric Deposits In Exhaust Piping During SIC CVI/CVD Processes By Introducing Water Vapor Into An Outlet Portion Of A Reaction Chamber
Systems for and methods of manufacturing a ceramic matrix composite include introducing a gaseous precursor into an inlet portion of a reaction furnace having a chamber comprising the inlet portion and an outlet portion that is downstream of the inlet portion, and delivering a mitigation agent, such as water vapor or ammonia, into an exhaust conduit in fluid communication with and downstream of the outlet portion of the reaction chamber so as to control chemical reactions occurring with the exhaust chamber. Introducing the gaseous precursor densities a porous preform, and introducing the mitigation agent shifts the reaction equilibrium to disfavor the formation of harmful and/or pyrophoric byproduct deposits within the exhaust conduit.
Manufacturing of a ceramic article from a metal preform or metal matrix composite preform provided by 3D-printing or 3D-weaving
The present invention relates to a method of manufacturing a ceramic article (3) from a metal or metal matrix composite preform (1) provided by 3D-printing or by 3D-weaving. The preform (1) is placed in a heating chamber (2), and a predetermined time-temperature profile is applied in order to controllably react the preform (1) with a gas introduced into the heating chamber (2). The metal, the gas and the time-temperature profile are chosen so as to induce a metal-gas reaction resulting in at least a part of the preform (1) transforming into a ceramic. Preferred embodiments of the invention comprises a first oxidation stage involving a metal-gas reaction in order to form a supporting oxide layer (5) at the surface of the metal, followed by a second stage in which the heating chamber (2) is heated to a temperature above the melting point of the metal to increase the kinetics of the chemical reaction. The invention also relates to a number of advantageous uses of a ceramic article manufactured as described.