A mandrel for a molding process that includes a first portion that has a first portion outer surface, a first portion inner surface, a first portion first end, and a first portion second end. A thickness of the first portion first end is greater than the first portion second end. A second portion has a second portion outer surface, a second portion inner surface, a second portion first end, and a second portion second end. A thickness of the second portion first end is smaller than the second portion second end. The first portion inner surface engages the second portion inner surface to form a mandrel that has a constant cross-section.

The disclosure relates to methods of fabricating of ceramic structures, and more particularly to methods of fabricating ceramic structures having profiled surfaces and more particularly to methods of fabrication of ceramic mirror blanks. In one embodiment, a method of forming a shaped ceramic article, includes: forming, via one of a cold-pressing process or pressure casting process, a green ceramic article comprising a first surface, an opposing second surface and at least one high aspect ratio feature shaped into at least one surface; heating the green featured ceramic part to form a debound featured ceramic part; and densifying the debound featured ceramic part via one of a pressureless sintering process or a hot-pressing process.

A component for use in a gas turbine engine is made from ceramic materials. The component is made from a core preform containing ceramic reinforcement fibers. A plurality of preform tows are applied on at least a portion of the core preform and extend along at least a portion of the core preform to provide an outermost surface. The core preform and the plurality of preform tows are infiltrated with ceramic matrix material to form a ceramic matrix composite component.

An inorganic felt material includes zirconia stabilized by at least one Group IIA material, such that the Group IIA material includes at least one of calcium (Ca), magnesium (Mg), or a combination thereof. The felt material may also include at least one Group III material.

A fiber preform defining an annulus extending along a central longitudinal axis. The fiber preform includes a plurality of layers extending in an axial direction and a circumferential direction relative to the longitudinal axis. Each layer of the plurality of layers includes a plurality of elongate fibers. The plurality of elongate fibers include a plurality of elongate axial fibers extending substantially in the axial direction and a plurality of elongate circumferential fibers extending substantially in the circumferential direction. The fiber preform also includes a plurality of radial fibers extending substantially in the radial direction. The plurality of radial fibers mechanically bind one or more adjacent layers of the plurality of layers. At least 40% of the plurality of elongate fibers extend substantially in the axial direction.

In order to enable stable provision of an upward release tube-type ceramic filter used in a molten metal bath and having a side wall with a height of 300 mm or greater, this method for manufacturing a ceramic filter, which is an upward release tube-type integrally molded article for removing unwanted substances from molten metal, has: a step for kneading a mixture of an aggregate comprising ceramic particles, a prescribed binding agent, and water to prepare a base material; a step for integrally forming an upward release tube-type ceramic filter precursor from the prepared base material; step for drying the precursor; a step for providing a retainer for the dried precursor for supporting a side wall of the precursor; a step for subsequently sintering the precursor; and a step for removing the retainer after sintering.

Articles of manufacture such as ceramic cores and cast metal turbomachinery components are disclosed herein, as well as methods of preparing such articles of manufacture. The articles and methods of manufacture are directed to improving the production and performance of internal combustion engines.

A method for forming a passage in a ceramic matrix composite component includes forming a core for a ceramic matrix composite component; embedding a hollow member into the core at a desired location for a passage in the ceramic matrix composite component; wrapping the core with a ceramic material; and inserting a rod through the hollow member and into the core.

A method of forming one or more high temperature co-fired ceramic articles, comprising the steps of:— a) forming a plurality of green compacts, by a process comprising dry pressing a powder comprising ceramic and organic binder to form a green compact; b) disposing a conductor or conductor precursor to at least one surface of at least one of the plurality of green compacts to form at least one patterned green compact; c) assembling the at least one patterned green compact with one or more of the plurality of green compacts or patterned green compacts or both to form a laminated assembly; d) isostatically pressing the laminated assembly to form a pressed laminated assembly; e) firing the pressed laminated assembly at a temperature sufficient to sinter the ceramic layers together.

The present disclosure relates to a method of forming a cast component and a method of forming a casting mold. The method is performed by connecting at least one wax gate component to a ceramic core-shell mold. The ceramic core-shell mold includes at least a filter, first core portion, a first shell portion, and at least one first cavity between the core portion and the first shell portion. The core-shell mold may manufactured using an additive manufacturing process and may include an integrated ceramic filter. At least a portion of the ceramic core-shell mold and the wax gate component is coated with a second ceramic material. The wax gate component is then removed to form a second cavity in fluid communication with the first cavity.