摘要:
A process for manufacturing a composite material part includes formation of a fibrous texture from refractory ceramic fibres, placement of the fibrous texture in a mould with interposition of a filtration layer between the fibrous texture and a discharge port, the filtration layer including a partially densified fibrous structure, pressure injection of a slurry containing a powder of refractory ceramic particles into the fibrous texture, drainage by the filtration layer of the slurry solvent having passed through the fibrous texture and retention of the powder of refractory ceramic particles within the texture by the filtration layer to obtain a fibrous preform including the fibrous texture filled with refractory ceramic particles and the filtration layer, heat treatment of the refractory ceramic particles present in the fibrous texture of the preform to form a composite material part including the fibrous texture densified by a refractory ceramic matrix and the filtration layer.
摘要:
The present invention relates to a suspension comprising 50-95% by weight of the total suspension (w/w) of at least one metallic material and/or ceramic material and/or polymeric material and/or solid carbon containing material; and at least 5% by weight of the total suspension of one or more fatty acids or derivatives thereof. In addition, the invention relates to uses of such suspension in 3D printing processes.
摘要:
The invention describes a method for producing ternary and binary ceramic powders and their thermal spraying capable of manufacturing thermal sprayed coatings with superior properties. Powder contain at least 30% by weight ternary ceramic, at least 20% by weight binary molybdenum borides, at least one of the binary borides of Cr, Fe, Ni, W and Co and a maximum of 10% by weight of nano and submicro-sized boron nitride. The primary crystal phase of the manufactured thermal sprayed coatings from these powders is a ternary ceramic, while the secondary phases are binary ceramics. The coatings have extremely high resistance against corrosion of molten metal, extremely thermal shock resistance and superior tribological properties at low and at high temperatures.
摘要:
A nanoheterostructure includes a first inorganic component and a second inorganic component one of which is a matrix, and the other of which is three-dimensionally and periodically arranged in the matrix, and has a three-dimensional periodic structure whose average value of one unit length of a repeated structure is 1 nm to 100 nm.
摘要:
An armor component including a body having a first portion including calcium boride compounds include non-stoichiometric calcium boride (CaBx) and stoichiometric calcium boride (TiO2) and having a density of at least about 80% theoretical density. In one aspect, the first portion can include a first phase comprising silicon carbide (SiC) and a second phase comprising calcium boride (TiO2). In another aspect, the first portion can further include a third phase comprising boron carbide (B4C).
摘要:
A general procedure applied to a variety of sol-gel precursors and solvent systems for preparing and controlling homogeneous dispersions of very small particles within each other. Fine homogenous dispersions processed at elevated temperatures and controlled atmospheres make a ceramic powder to be consolidated into a component by standard commercial means: sinter, hot press, hot isostatic pressing (HIP), hot/cold extrusion, spark plasma sinter (SPS), etc.
摘要:
A lanthanum boride sintered body includes a phase including lanthanum and silicon at grain boundaries between crystal grains of lanthanum boride. In this lanthanum boride sintered body, the phase exists in various configurations such as a phase present at a triple point of grain boundary, and a phase present along the grain boundary. This phase is based on a lanthanum silicide (represented by the composition formula LaSix (0
摘要:
A method of forming a ceramic matrix composite structure. The method comprises forming at least one prepregged composite material comprising a ceramic fiber preform and a pre-ceramic matrix slurry. The at least one prepregged composite material is placed over at least one surface of a tool using an advanced fiber placement apparatus to form an at least partially uncured composite material structure. The at least partially uncured composite material structure is exposed at least to elevated temperatures to convert the at least partially uncured composite material structure into a ceramic matrix composite structure. A system for forming a ceramic matrix composite structure, an advanced fiber placement apparatus, and a ceramic matrix composite structure are also described.
摘要:
Laboratory heat press consists of furnace part equipped with dilatometer which is placed beneath removable double-acting pneumatic cylinder anchored on four shafts, of power supply and of computer which regulates process and collects data, while in the working space is situated graphite press die with sample, which is placed on sliding piston holder and the device is equipped with control electronics. Heating equipment is graphite element, and around the element are situated graphite shields made from solid graphite and graphite wool insulation. Outer shell of furnace and both flanges are water cooled. Flanges are equipped with holes for thrust pistons and the furnace shell contains hole for connecting the vacuum pump and hole for installation of the pyrometer. Graphite pressing die with sample is equipped with pistons, which are influenced by power from double-acting pneumatic cylinder, while on the both graphite pistons are graphite radiative rings and between them is graphite wool.
摘要:
New cermets with improved properties and applications are provided. These new cermets have lower density and/or higher hardness than B4C cermet. By incorporating other new ceramics into B4C powders or as a substitute for B4C, lower densities and/or higher hardness cermets result. The ceramic powders have much finer particle size than those previously used which significantly reduces grain size of the cermet microstructure and improves the cermet properties.