The present invention relates to a metal matrix composite (MMC). The MMC includes a preform formed from a composition having ceramic particles and ceramic fibers and defining a plurality of voids. The metal matrix composite also includes a support element, such as a metal, disposed within the voids of the preform. The MMC has a wear surface defined by both the preform and the support element.

The present invention relates to a metal matrix composite (MMC). The MMC includes a preform formed from a composition having ceramic particles and ceramic fibers and defining a plurality of voids. The metal matrix composite also includes a support element, such as a metal, disposed within the voids of the preform. The MMC has a wear surface defined by both the preform and the support element.

A mandrel for a molding process. The mandrel includes a first portion that has a first draft surface and a second draft surface. A second portion and a third portion are included. The second portion has a third draft surface and the third portion has a fourth draft surface wherein the first draft surface engages the third draft surface and the second draft surface engages the fourth draft surface. A channel extends along a length of the mandrel at an interface between the first, second, and third portions such that the second portion does not contact the third portion.

A mandrel for a molding process. The mandrel includes a first portion that has a first draft surface and a second draft surface. A second portion and a third portion are included. The second portion has a third draft surface and the third portion has a fourth draft surface wherein the first draft surface engages the third draft surface and the second draft surface engages the fourth draft surface. A channel extends along a length of the mandrel at an interface between the first, second, and third portions such that the second portion does not contact the third portion.

A substantially metal-free exhaust subsystem includes an exterior housing formed of polymer; and a pipe formed of a layered fibers formed at least partially of glass, and bound by an inorganic binder. The fibers may be glass or ceramic, and may define micro-pores on the interior of the pipe that aid in absorbing acoustic energy, and thereby attenuating exhaust noise.

A substantially metal-free exhaust subsystem includes an exterior housing formed of polymer; and a pipe formed of a layered fibers formed at least partially of glass, and bound by an inorganic binder. The fibers may be glass or ceramic, and may define micro-pores on the interior of the pipe that aid in absorbing acoustic energy, and thereby attenuating exhaust noise.

A substantially metal-free exhaust subsystem includes an exterior housing formed of polymer; and a pipe formed of a layered fibers formed at least partially of glass, and bound by an inorganic binder. The fibers may be glass or ceramic, and may define micro-pores on the interior of the pipe that aid in absorbing acoustic energy, and thereby attenuating exhaust noise.

A substantially metal-free exhaust subsystem includes an exterior housing formed of polymer; and a pipe formed of a layered fibers formed at least partially of glass, and bound by an inorganic binder. The fibers may be glass or ceramic, and may define micro-pores on the interior of the pipe that aid in absorbing acoustic energy, and thereby attenuating exhaust noise.

A mandrel suitable for supporting an airfoil preform includes a first piece extending along a longitudinal axis of the mandrel, and a second piece in physical contact with the first piece at first interface region and extending along the longitudinal axis of the mandrel. The first piece is formed from a first material, and the second piece is formed from a second material.

A mandrel suitable for supporting an airfoil preform includes a first piece extending along a longitudinal axis of the mandrel, and a second piece in physical contact with the first piece at first interface region and extending along the longitudinal axis of the mandrel. The first piece is formed from a first material, and the second piece is formed from a second material.