A composition which comprises a soluble or partially soluble phosphate, a refractory material and less than 1% of an oxide or hydroxide of magnesium or calcium. The composition may be mixed with water to form an investment casting slurry into which a wax pattern may be dipped. Slurry coated onto the pattern may be set by applying a stucco composition which comprises an oxide or hydroxide of magnesium or calcium. Coats of set slurry may be built up on the pattern to form an investment casting shell.

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.

A carbon fiber preform that includes a plurality of fibrous layers stacked together and a plurality of sacrificial fibers that bind the plurality of fibrous layers together, where at least one fibrous layer of the plurality of fibrous layers includes a plurality of carbon fibers or carbon fiber precursor fibers.

A single crystal ceramic core composition has an inorganic portion and an organic portion. The inorganic portion makes up about 85% by weight of the total weight of the ceramic core composition, and the organic portion makes up about 15% by weight of the total weight of the ceramic core composition. The inorganic portion includes about 94 to 98% by weight spherical fused silica, and about 2 to 6% by weight zircon flour. The organic portion includes about 84 to 88% by weight binder, about 1 to 2% by weight dye, about 6 to 12% by weight surfactant, and about 1 to 5% by weight polymeric fiber.

Methods of producing continuous (or discontinuous) boron carbide fibers. The method comprises reacting a continuous or discontinuous carbon fiber material and a boron oxide gas within a temperature range of from approximately 1400 C. to approximately 2200 C. Articles including such partially or fully converted fibers may be provided, including such reinforcing fibers in a matrix of ceramic (a CMC), in metal (a MMC), or other matrix (e.g., polymer, etc.).

A preceramic resin formulation comprising a polycarbosilane preceramic polymer, an organically modified silicon dioxide preceramic polymer, and, optionally, at least one filler. The preceramic resin formulation is formulated to exhibit a viscosity of from about 1,000 cP at about 25? C. to about 5,000 cP at a temperature of about 25? C. The at least one filler comprises first particles having an average mean diameter of less than about 1.0 ?m and second particles having an average mean diameter of from about 1.5 ?m to about 5 ?m. Impregnated fibers comprising the preceramic resin formulation are also disclosed, as is a composite material comprising a reaction product of the polycarbosilane preceramic polymer, organically modified silicon dioxide preceramic polymer, and the at least one filler. Methods of forming a ceramic matrix composite are also disclosed.

Methods for preparing ceramic matrix composites using melt infiltration and chemical vapor infiltration are provided as well as the resulting ceramic matrix composites. The methods and products include the incorporation of sacrificial fibers to provide improved infiltration of the fluid infiltrant. The sacrificial fibers are removed, such as decomposed during pyrolysis, resulting in the formation of regular and elongate channels throughout the ceramic matrix composite. Infiltration of the fluid infiltrant can then take place using the elongate channels resulting in improved density and an improved ceramic matrix composite product.

Disclosed is a method of making high temperature fiber including incorporating an inorganic atom into a polymer precursor fiber to form a modified polymer precursor fiber and converting the modified polymer precursor fiber to a high temperature fiber having a bonded inorganic atom.

A method for producing carbonized or graphitized molding parts is particularly simple to implement and also allows producing complex molding parts without mechanical post-processing. This is achieved by the production of a pourable liquid polymer mixture which is as homogenized as possible, consisting of a carbon granulate, pitch, soot or graphite powder and polyacrylnitrile dissolved in a solvent, filling the liquid polymer mixture into a casting mold and immersing the filled casting mold in water over a predetermined period of time until the polymer mixture is sufficiently cured and dimensionally stable, and subsequent breaking of the casting mold and stabilizing the prefabricated cured molding part by uniform heating up in a furnace in air at a predefined temperature for stabilizing and degassing volatile constituents, and performing a high-temperature treatment for carbonizing or graphitizing the molding part in a furnace under protective gas.

Exemplary embodiments relate to a batch for producing an unshaped refractory ceramic product, to a method for producing a fired refractory ceramic product, to a fired refractory ceramic product and to the use of an unshaped refractory ceramic product.