Embodiments relate to polycrystalline diamond compacts (PDCs) that are less susceptible to liquid metal embrittlement damage due to the use of at least one transition layer between a polycrystalline diamond (PCD) layer and a substrate. In an embodiment, a PDC includes a PCD layer, a cemented carbide substrate, and at least one transition layer bonded to the substrate and the PCD layer. The at least one transition layer is formulated with a coefficient of thermal expansion (CTE) that is less than a CTE of the substrate and greater than a CTE of the PCD layer. At least a portion of the PCD layer includes diamond grains defining interstitial regions and a metal-solvent catalyst occupying at least a portion of the interstitial regions. The diamond grains and the catalyst collectively exhibit a coercivity of about 115 Oersteds or more and a specific magnetic saturation of about 15 Gauss.Math.cm.sup.3/grams or less.

Composite components that include features that provide improved wear characteristics at the interface between the composite component and a second component are provided. As one example, a composite component can include an integrally formed discontinuous molded tape (DMT) that defines a wear interface between the component and a second component. The wear interface defined by the DMT may provide improved durability of the composite component and may facilitate more uniform wear at the interface, among other benefits. Methods for manufacturing composite components having discontinuous molded tape wear interfaces are also provided.

A gas turbine engine component includes a gas turbine engine component body formed of a ceramic matrix composite material having at least one fastener integrally formed with the gas turbine engine component body as a single-piece structure. The gas turbine engine component body initially comprises a rigidized preform structure formed from a polymer based material. The at least one fastener connects the gas turbine engine component body to an engine support structure.

An assembly for use in a gas turbine engine and method for making the same are described herein. The assembly comprising a CMC component, a metallic component spaced apart from the CMC component, and a spacer. The spacer having a first surface in contact with the CMC and a second surface opposite the first surface in contact with the metallic component, the spacer comprising a CMC substantially free of silicon metal with a porosity of between about 5 percent and about 40 percent by volume to chemically isolate the CMC component from the metallic component.

A method for the joining of ceramic pieces with a hermetically sealed joint comprising brazing a layer of joining material between the two pieces. The wetting and flow of the joining material is controlled by the selection of the joining material, the joining temperature, the joining atmosphere, and other factors. The ceramic pieces may be on a non-diffusable type, such as aluminum nitride, alumina, beryllium oxide, and zirconia, and the pieces may be brazed with an aluminum alloy under controlled atmosphere. The joint material is adapted to later withstand both the environments within a process chamber during substrate processing, and the oxygenated atmosphere which may be seen within the shaft of a heater or electrostatic chuck.

Thermally-conductive ceramic and ceramic composite components suitable for high temperature applications, systems having such components, and methods of manufacturing such components. The thermally-conductive components are formed by a displacive compensation of porosity (DCP) process and are suitable for use at operating temperatures above 600 C. without a significant reduction in thermal and mechanical properties.

A ceramic matrix composite article includes a chemical vapor infiltration ceramic matrix composite base portion including ceramic fiber reinforcement material in a ceramic matrix material having between 0% and 5% free silicon. The ceramic matrix composite article further includes a melt infiltration ceramic matrix composite covering portion including a ceramic fiber reinforcement material in a ceramic matrix material having a greater percentage of free silicon than the chemical vapor infiltration ceramic matrix composite base portion.

Methods for repairing composite cylindrical components are provided. One exemplary method for repairing a cylindrical component defining an axial direction, a radial direction, and a circumferential direction includes removing a damaged region of the cylindrical component. A flange extending from a cylindrical body of the cylindrical component is included in the damaged region. One or more arc segments that extend along the circumferential direction are connected with the existing cylindrical component. At least one of the arc segments includes a prefabricated flange. One or more plies are laid up to connect the arc segments with the existing cylindrical component to repair the damaged region of the cylindrical body and the prefabricated flange formed integrally with one of the arc segments replaces the damaged portion of the flange. Repaired cylindrical components are also provided.

A device includes a ceramic substrate formed of a first material, a polishable layer formed of a different material, and an interface between the ceramic substrate and the polishable layer. The interface is formed by infiltration of molten elemental silicon, and bonds the ceramic substrate and the polishable layer together. The device may include an optical device such as, for example, mirror or a beam dump. A method of making a device from a green-state structure and a polishable layer is also disclosed. The method includes infiltrating elemental silicon into and through the green-state structure, to form a substrate of a multi-phase ceramic material from the green-state structure, and to reactively bond the substrate and the polishable layer together.

A method for making a braking band (2) for a brake disc (1) for a disc brake, comprising the following steps: a) preparing a mold (10) having an inner cavity (11), which comprises a first portion (11a) of a shape corresponding to the braking band (2) to be made; b) preparing a band preform (20) comprising a central preform (200), an upper outer preform (201) and a lower outer preform (202), said central preform (200) being made of porous ceramic material comprising silicon carbide (SiC), said upper outer preform (201) and lower outer preform (202) being made of porous ceramic material comprising silicon carbide (SiC) and infiltrated with silicon (SiC+Si), wherein a carbon barrier layer (201a, 200a, 200b, 202a) made of carbon is interposed between the upper outer preform (201) and the central preform (200) and between the lower outer preform (202) and the central preform (200), said preforms (200, 201, 202) having the shape of the braking band (2) to be made; c) placing said band preform (20) inside the mold at the first portion (11a) of said inner cavity (11); and d) injecting a liquid or semi-solid aluminum alloy inside the entire inner cavity (11) of the mold (11) to infiltrate the central preform (200) of said band preform (20) made of porous ceramic material with said aluminum alloy, obtaining at the first portion (11a) an aluminum metal matrix composite reinforced by said central preform (200) which defines the braking band (2) to be made. A braking band and a brake disc are made with at least the aforesaid method.