摘要:
A method and apparatus for forming a plurality of fibers from (e.g., CVD) precursors, including a reactor adapted to grow a plurality of individual fibers; and a plurality of independently controllable lasers, each laser of the plurality of lasers growing a respective fiber. A high performance fiber (HPF) structure, including a plurality of fibers arranged in the structure; a matrix disposed between the fibers; wherein a multilayer coating is provided along the surfaces of at least some of the fibers with an inner layer region having a sheet-like strength; and an outer layer region, having a particle-like strength, such that any cracks propagating toward the outer layer from the matrix propagate along the outer layer and back into the matrix, thereby preventing the cracks from approaching the fibers. A method of forming an interphase in a ceramic matrix composite material having a plurality of SiC fibers, which maximizes toughness by minimizing fiber to fiber bridging, including arranging a plurality of SiC fibers into a preform; selectively removing (e.g., etching) silicon out of the surface of the fibers resulting in a porous carbon layer on the fibers; and replacing the porous carbon layer with an interphase layer (e.g., Boron Nitride), which coats the fibers to thereby minimize fiber to fiber bridging in the preform.
摘要:
An article includes a substrate and a coating on the substrate. The coating includes a compound of aluminum, boron and nitrogen in a continuous chemically bonded network having Al—N bonds and B—N bonds. Also disclosed is an article wherein the substrate is a plurality of fibers and the coating is a conformed coating of a compound of aluminum, boron and nitrogen having Al—N bonds and B—N bonds. The fibers are disposed in a matrix. Also disclosed is a method of protecting an article from environmental conditions. The method includes protecting a substrate that is susceptible to environmental chemical degradation using a coating that includes a compound of aluminum, boron and nitrogen having Al—N bonds and B—N bonds.
摘要:
Methods for coating a fiber are provided. The method can include unwinding a silicon carbide-containing fibrous material from a bobbin rotatably mounted around an axle and forming a boron nitride coating onto the silicon carbide-containing fibrous material. The bobbin is moved along the axial direction such that the silicon carbide-containing fibrous material defines an unwind angle with the axial direction, with the unwind angle being maintained between about 80° to about 100°.
摘要:
A method of forming a composite article includes impregnating an inorganic fiber preform with a slurry composition. The slurry composition includes a particulate, a solvent, and a pre-gellant material. Gelling of the pre-gellant material in the slurry composition is initiated to immobilize the particulate and yield a gelled article, and substantially all solvent is removed from the gelled article to form a green composite article. The green composite article is then infiltrated with a molten infiltrant to form the composite article.
摘要:
A titanium oxide-based supercapacitor electrode material and a method of manufacturing same. A reactive substance of the titanium oxide-based supercapacitor electrode material is a conductive titanium oxide. The conductive titanium oxide is a sub-stoichiometric titanium oxide, reduced titanium dioxide, or doped reduced titanium dioxide obtained by further doping an element in reduced titanium dioxide. The titanium oxide-based supercapacitor electrode material has a carrier concentration greater than 1018 cm−3, and the titanium oxide-based supercapacitor electrode material has a specific capacitance 20 F/g to 1,740 F/g at a charge/discharge current of 1 A/g.
摘要翻译:一种基于氧化钛的超级电容器电极材料及其制造方法。 氧化钛系超级电容器电极材料的反应性物质为导电性氧化钛。 导电氧化钛是通过在还原的二氧化钛中进一步掺杂元素而获得的亚化学计量的氧化钛,还原的二氧化钛或掺杂的还原二氧化钛。 基于钛氧化物的超级电容器电极材料的载流子浓度大于1018cm-3,氧化钛基超级电容器电极在充电/放电电流为1A时的比电容为20F / g至1740F / g /G。
摘要:
In one embodiment, a composition (10) to be mixed with a molten metal to make a metal matrix composite, the composition characterized by: a ceramic reinforcing filler (12), the ceramic reinforcing filler not being wettable by molten aluminum and/or not being chemically stable in molten aluminum, the ceramic reinforcing filler being coated with a ceramic material, the ceramic material being wettable by and chemically stable in molten aluminum. In a related embodiment, a composition (20) to make a porous preform to be infiltrated by molten metal to make a metal matrix composite, the composition characterized by: a ceramic reinforcing filler (23), the ceramic reinforcing filler not being wettable by molten aluminum, the ceramic reinforcing filler being coated with a ceramic material (22) and optionally with a metal (21) such as nickel, the ceramic material being wettable by molten aluminum. The ceramic material can be coated on the ceramic reinforcing filler by a vacuum deposition technique such as vacuum sputtering.
摘要:
The method comprises:using chemical vapor infiltration to form a first continuous interphase on the fibers of a fiber structure made of refractory fibers, the interphase having a thickness of no more than 100 nanometers;impregnating the fiber structure with a consolidation composition comprising a carbon or ceramic precursor resin;forming a fiber preform that is consolidated by shaping the impregnated fiber structure and using pyrolysis to transform the resin into a discontinuous solid residue of carbon or ceramic;using chemical vapor infiltration to form a second continuous interphase layer; anddensifying the preform with a refractory matrix.This preserves the capacity of the fiber structure to deform so as to enable a fiber preform to be obtained that is of complex shape, while nevertheless guaranteeing the presence of a continuous interphase between the fibers and the matrix.
摘要:
Fibrous monolith composites having architectures that provide increased flaw insensitivity, improved hardness, wear resistance and damage tolerance and methods of manufacture thereof are provided for use in dynamic environments to mitigate impact damage and increase wear resistance.
摘要:
Small diameter silicon carbide-containing fibers are provided in a bundle such as a fiber tow that can be formed into a structure where the radii of curvature is not limited to 10-20 inches. An aspect of this invention is directed to impregnating the bundles of fibers with the slurry composition to substantially coat the outside surface of an individual fiber within the bundle and to form a complex shaped preform with a mass of continuous fibers.
摘要:
A process comprising the steps of: a) providing a fiber preform comprising a non-oxide ceramic fiber with at least one coating, the coating comprising a coating element selected from the group consisting of carbon, nitrogen, aluminum and titanium, and the fiber having a degradation temperature of between 1400.degree. C. and 1450.degree. C., b) impregnating the preform with a slurry comprising silicon carbide particles and between 0.1 wt % and 3 wt % added carbon c) providing a cover mix comprising: i) an alloy comprising a metallic infiltrant and the coating element, and ii) a resin, d) placing the cover mix on at least a portion of the surface of the porous silicon carbide body, e) heating the cover mix to a temperature between 1410.degree. C. and 1450.degree. C. to melt the alloy, and f) infiltrating the fiber preform with the melted alloy for a time period of between 15 minutes and 240 minutes, to produce a ceramic fiber reinforced ceramic composite.