A non woven web including a multiplicity of non-respirable, polycrystalline, aluminosilicate ceramic filaments entangled to form a cohesive mat, the polycrystalline, aluminosilicate ceramic filaments having an average mullite percent of at least 75 wt %. The cohesive mat preferably exhibits a compression resilience after 1,000 cycles at 900° C. when measured according to the Fatigue Test, of at least 30 kPa. Insulation articles including the cohesive mats or formed by chopping the ceramic mats into ceramic fibers, pollution control devices including the insulation articles, and methods of making the non-respirable, polycrystalline, aluminosilicate ceramic filaments and fibers, nonwoven webs, insulation articles, and pollution control devices, are also described.

The invention relates to ZrO.sub.2-reinforced mullite fibers having a content of at least 0.1 wt. % of crystalline ZrO.sub.2, said mullite fibers being distinguished by significantly improved mechanical properties compared to unmodified mullite fibers. The invention further relates to processes for manufacturing such fibers, green fibers produced as an intermediate product in the process, and the use of the ZrO.sub.2-reinforced mullite fibers in fibre-matrix composite materials.

A needled blanket is provided comprising melt-formed inorganic fibres having an overall composition in weight percent SiO.sub.2: 47 to 65% Al.sub.2O.sub.3: 35 to 53%the blanket having a shot content, of shot >45 .Math.m, of less than 51 wt%, a specific surface area (BET) > 0.25 m.sup.2.g.sup.-1.also disclosed are fibres for producing such blankets, and self-supporting products made from such fibres.

An object is to provide metal element-having ceramic continuous fibers suitable for use in the production of highly heat-resistant CMCs, and a CMC made therewith. The ceramic continuous fibers comprise ceramic continuous fibers and at least one metal element therein, with the concentration by mass of the metal element being 10 ppm or more and 1000 ppm or less.

A method of making a ceramic fiber tow and the system regarding the same may be included. The method may include commingling a plurality of ceramic fibers with a fugitive fiber to form a single ceramic fiber tow. The fugitive fiber may be positioned between at least two ceramic fibers included in the single ceramic fiber tow. The method may further include forming a porous ceramic preform including at least the single ceramic fiber tow. The method may further include removing the fugitive fiber from the ceramic fiber tow leaving a space between at least two ceramic fibers of the single ceramic fiber tow. The method may further include replacing the spaces between ceramic fibers included in the ceramic fiber tows with a ceramic matrix.

An alumina fiber aggregate that is formed of alumina short fibers and has been subjected to needling treatment, wherein the alumina short fibers have an average fiber diameter of 6.0 μm or more and 10.0 μm or less and a specific surface area of 0.2 m.sup.2/g or more and 1.0 m.sup.2/g or less, and a residual percentage (%) of high-temperature-cycle opened gap pressure of the alumina fiber aggregate is 45% or more. A value obtained by subtracting twice the standard error of a length-weighted geometric mean diameter of fiber diameters of the alumina short fibers from the length-weighted geometric mean diameter is 6.0 μm or more. A proportion of alumina short fibers having a fiber diameter of more than 10.0 μm is preferably 5.0% or less on a number basis.

A complex ceramic particle and ceramic composite material may be made of a pretreated coal dust and a polymer derived ceramic that is mixed together and pyrolyzed in a nonoxidizing atmosphere. Constituent portions of the particle mixture chemically react causing particles to increase in density and reduce in size during pyrolyzation, yielding a particle suitable for a plurality of uses including composite articles and proppants.

An inorganic fiber containing silica, alumina, one or more alkali metal oxides, and one or more of alkaline earth metal oxides, transition metal oxides, or lanthanide series metal oxides. The inorganic fiber exhibits good thermal performance at use temperatures of 1260° C. and greater, retains mechanical integrity after exposure to the use temperatures, is free of crystalline silica upon devitrification, is alkali flux resistant, exhibits low bio-persistence in an acidic medium, and exhibits low dissolution in a neutral medium. Also provided are thermal insulation products incorporating the inorganic fibers, a method for preparing the inorganic fiber and a method of thermally insulating articles using thermal insulation prepared from the inorganic fibers.

An alumina-silica hydrate fiber for thermal protection in the most hazardous environments experienced by firefighters. The fiber has a combination of heat resistance at temperatures above 1,000° C. and an endothermic behavior when heated. Its endothermic condensation reaction releases up to 12% water upon heating, thereby contributing to the thermal insulating properties. The fibers are extremely soft to the touch and do not irritate the skin. They are also non-respirable in the deep lung, so they can be used safely without risk of inhalation. The fabric is sufficiently lightweight and flexible as well, allowing firefighters to move easily. These properties of alumina-silica hydrate fibers enable their use for apparel.

A method of producing fibers includes exposing an inorganic composition to a plasma plume, where the plasma plume has a temperature of at least 1500° C. and a bulk velocity of at least 350 m/s. A system for producing fibers includes a plasma torch to produce the plasma plume and a feeding device to introduce the inorganic composition to the plasma plume.