2922 results about "Ceramic matrix composite" patented technology

A method for producing shaped articles of ceramic composites provides a high degree of dimensional tolerance to these articles. A fiber preform is disposed on a surface of a stable formed support, a surface of which is formed with a plurality of indentations, such as grooves, slots, or channels. Precursors of ceramic matrix materials are provided to the fiber preform to infiltrate from both sides of the fiber preform. The infiltration is conducted under vacuum at a temperature not much greater than a melting point of the precursors. The melt-infiltrated composite article substantially retains its dimension and shape throughout the fabrication process.

A method of manufacturing a composite structure uses a layer of an insulating material (22) as a mold for forming a substrate of a ceramic matrix composite (CMC) material (24). The insulating material may be formed in the shape of a cylinder (10) with the CMC material wound on an outer surface (14) of the cylinder to form a gas turbine combustor liner (20). Alternatively, the insulating material may be formed in the shape of an airfoil section (32) with the CMC material formed on an inside surface (36) of the insulating material. The airfoil section may be formed of a plurality of halves (42, 44) to facilitate the lay-up of the CMC material onto an easily accessible surface, with the halves then joined together to form the complete composite airfoil. In another embodiment, a box structure (102) defining a hot gas flow passage (98) is manufactured by forming insulating material in the shape of opposed airfoil halves (104) joined at respective opposed ends by platform members (109). A layer of CMC material (107) is then formed on an outside surface of the insulating material. A number of such composite material box structures are then joined together to form a vane ring (100) for a gas turbine engine.

A mounting arrangement (10) for a multivane segment (12) of ceramic matrix composite (CMC) composition positioned between outer and inner metallic rings (14, 16). Selected ones of the vanes (18a) of the multivane segment surround internal struts (24) joining the outer and inner rings. Spring members (26, 28) accommodate differential thermal growth between the multivane segment and the outer and inner rings, and a compliant material (30) seals against gas leakage around the segments.

Aspects of the invention are directed to systems for reducing the cooling requirements of a ring seal in a turbine engine. In one embodiment, the ring seal can be made of a ceramic material, such as a ceramic matrix composite. The ceramic ring seal can be connected to metal isolation rings by a plurality of pins. The hot gas face of the ring seal can be coated with a thermal insulating material. In another embodiment, the ring seal can be made of metal, but it can be operatively associated with a ceramic heat shield. The metal ring seal can carry the mechanical loads imposed during engine operation, and the heat shield can carry the thermal loads. By minimizing the amount of ring seal cooling, the ring seal systems according to aspects of the invention can result in improved engine performance and emissions.

A vane has an airfoil shell and a spar within the shell. The vane has an outboard shroud at an outboard end of the shell and an inboard platform at an inboard end of the shell. The spar has a first chamber essentially along the suction side and a second chamber along the pressure side opposite the first chamber.

Aspects of the invention are directed to a ring seal segment having a base portion and a frame portion. The base portion and the frame portion are a unitary structure. The frame portion is made of four unitary side walls: a forward wall, an aft wall and a pair of transverse side walls. The side walls can be arranged in a rectangular configuration. At least a part of the base portion can be coated with a thermal insulating material. A ring seal segment according to aspects of the invention is well suited to withstand the expected operational loads in the turbine section. The transverse side walls can provide bending strength to the base and can strengthen the forward and aft side walls. Transition regions between the side walls and the base portion are strengthened by three perpendicular planes that cooperate to provide structural strength to the ring seal segment.

A method for forming interphase layers in ceramic matrix composites. The method forms interphase layers in ceramic matrix composites thereby enabling higher matrix densities to be achieved without sacrificing crack deflection and / or toughness. The methods of the present invention involve the use fugitive material-coated fibers. These fibers are then infiltrated with a ceramic matrix slurry. Then, the fugitive material is removed and the resulting material is reinfiltrated with an interphase layer material. The ceramic matrix composite is then fired. Additional steps may be included to densify the ceramic matrix or to increase the strength of the interphase layer. The method is useful for the formation of three dimensional fiber-reinforced ceramic matrix composites envisioned for use in gas turbine components.

A gas turbine combustor includes a substantially cylindrical combustor liner located substantially concentrically within a flow sleeve, the combustor liner composed through a ceramic matrix composite material, a forward end of the combustor liner provided with a plurality of circumferentially arranged bolt holes. An inner metal ring is located about an outside surface of the forward end of the combustor liner, the inner metal ring provided with a second plurality of circumferentially spaced bolt holes, with a plurality of bolts extending through the first and second pluralities of bolt holes and secured by self-locking nuts. An outer metal ring is spaced radially outwardly of the inner metal ring, with a plurality of circumferentially spaced struts extending between the inner and outer rings.

The annular combustion chamber having ceramic matrix composite material walls is mounted inside a metal casing by linking members fastened to the chamber by brazing. The linking members comprise a plurality of inner linking tabs and a plurality of outer linking tabs connecting the chamber to the inner and outer metal shrouds of the casing, each linking tab has a first portion fastened to the outside surface of a wall of the combustion chamber by brazing, the first portions of the linking tabs being spaced apart from one another circumferentially so that the brazed connections between the chamber and the linking members occupy a set of limited zones that are spaced apart from one another.