An automated preparation method of a SiC.sub.f/SiC composite flame tube, comprising the following steps: preparing an interface layer for a SiC fiber by a chemical vapor infiltration process, and obtaining the SiC fiber with a continuous interface layer; laying a unidirectional tape on the SiC fiber with the continuous interface layer and winding the SiC fiber with the continuous interface layer to form and obtaining a preform of a net size molding according to a fiber volume and a fiber orientation obtained in a simulation calculation; and adopting a reactive melt infiltration process and the chemical vapor infiltration process successively for a densification and obtaining a high-density SiC.sub.f/SiC composite flame tube in a full intelligent way. The SiC.sub.f/SiC composite flame tube prepared by the present disclosure not only has a high temperature resistance, but also has a low thermal expansion coefficient, high thermal conductivity and high thermal shock resistance.

Methods are described to make strong, tough, and lightweight whisker-reinforced glass-ceramic composites through a self-toughening structure generated by viscous reaction sintering of a complex mixture of oxides. The invention further relates to strong, tough, and lightweight glass-ceramic composites that can be used as proppants and for other uses.

A ceramic brush seal for a gas turbine engine, and a process for manufacturing the seal are provided. In one example, the process includes deinfiltrating an edge of a plurality of plies having a preimpregnated configuration. The edge is defined by a plurality of ceramic fibers extending away from a portion edge of a matrix infiltrated portion of each of the plies. In another example, the process includes masking an edge of a plurality of plies, the edge being defined by a plurality of ceramic fibers extending away from a portion edge of a body portion of each of the plies, and infiltrating the body portion of the plurality of plies with a ceramic matrix slurry. The plies are stacked, formed into a green body and then fired to form the component. The plies may include oxide/oxide woven ceramic fiber plies.

Provided herein is a method of manufacturing a nanoscale coated network, which includes providing nanofibers, capable of forming a network in the presence of a liquid vehicle and providing a nanoscale solid substance in the presence of the liquid vehicle. The method may also include forming a network of the nanofibers and the nanoscale solid substance and redistributing at least a portion of the nanoscale solid substance within the network to produce a network of nanofibers coated with the nanoscale solid substance. Also provided herein is a nanoscale coated network with an active material coating that is redistributed to cover and electrochemically isolate the network from materials outside the network.

A thermostructural composite material part including carbon or ceramic fiber reinforcement densified by a matrix having at least one thin portion in which: the thickness of the part is less than 2 mm, or indeed less than 1 mm; the fiber reinforcement is made as a single thickness of multilayer fabric made of spread yarns having a weight of not less than 200 tex; the fiber volume ratio lies in the range 25% to 45%; and the ratio between the number of layers of the multilayer fabric and the thickness in millimeters of the part is not less than four.

A process of producing a porous electrode substrate, including: dispersing first short carbon fibers and producing a first precursor sheet not having a three-dimensional entangled structure of the first short carbon fibers; treating the first precursor sheet such that the first short carbon fibers in the first precursor sheet are entangled and that a second precursor sheet having a three-dimensional entangled structure of the first short carbon fibers is obtained; dispersing second short carbon fibers on the second precursor sheet such that a porous electrode precursor sheet including the second precursor sheet and a third precursor sheet not having a three-dimensional entangled structure of the second short carbon fibers and stacked on the second precursor sheet is obtained; and carbonization treating the porous electrode substrate precursor sheet at a temperature of at least 1000° C. to obtain the porous electrode substrate.

Ceramic matrix composite articles include, for example, a plurality of unidirectional arrays of fiber tows in a matrix having a monomodal pore size distribution, and a fiber volume fraction between about 15 percent and about 35 percent. The articles may be formed by, for example, providing a shaped preform comprising a prepreg tape layup of unidirectional arrays of fiber tows, a matrix precursor, and a pore former, curing the shaped preform to pyrolyze the matrix precursor and burnout the pore former so that the shaped preform comprises the unidirectional arrays of fiber tows and a porous matrix having a monomodal pore size distribution, and subjecting the cured shaped preform to chemical vapor infiltration to densify the porous matrix so that the ceramic matrix composite article has a fiber volume fraction between about 15 percent and about 35 percent.

A method for treating a field operated component is disclosed which includes providing the component including a ceramic matrix composite and removing a first portion of the component, forming a first exposed surface on the component. The method further includes providing a second portion including the composite, the second portion having a second exposed surface including a conformation adapted to mate with the first exposed surface. The second portion is positioned in association with the component so as to replace the first portion, and the second portion and the component are joined to form a treated component. Another method is disclosed wherein the component is a turbine component which further includes removing an environmental barrier coating from the component, arranging and conforming the first exposed surface and the second exposed surface to define a joint, and applying an environmental barrier coating to the treated component.

Disclosed are an inorganic nanofiber characterized in that the average fiber diameter is 2 μm or less, the average fiber length is 200 μm or less, and the CV value of the fiber length is 0.7 or less; and a method of manufacturing the same. In the manufacturing method, an inorganic nanofiber sheet consisting of inorganic nanofibers having an average fiber diameter of 2 μm or less is formed by electrospinning, and then, the inorganic nanofiber sheet is pressed using a press machine and crushed so that the average fiber length becomes 200 μm or less, and the CV value of the fiber length becomes 0.7 or less.

Fiber tows including a heat-activatable sizing are described. The sizing compositions have a first modulus at 25° C. of at least 150 megapascals (MPa) and no greater than 400 MPa; and a second modulus of 100,000 pascals (Pa) at a temperature of no greater than 160° C. Methods of preparing articles from such sized fiber tows and the articles comprising such sized fiber tows, including unidirectional and bidirectional constructions are also described.