Abstract: A process for producing a silicon-containing CMC article that exhibits improved physical, mechanical, and microstructural properties at elevated temperatures exceeding the melting point of silicon. The process entails producing a body containing a ceramic reinforcement material in a solid matrix that comprises solid elemental silicon and/or silicon alloy and a ceramic matrix material. The ceramic matrix composite article is produced by at least partially removing the solid elemental silicon and/or silicon alloy from the solid matrix and optionally reacting at least part of the solid elemental silicon and/or silicon alloy in the solid matrix to form one or more refractory materials. The solid elemental silicon and/or silicon alloy is sufficiently removed from the body to enable the ceramic matrix composite article to structurally and chemically withstand temperatures above 1405° C.

Abstract: A method for inhibiting diffusion of silicon into a support structure from a component formed of a silicon-containing material, and an assembly formed thereby. The component is supported and contacted by the support structure so as to define a contact interface therebetween. An barrier coating is present on the component and/or the support structure, so as to be disposed at the contact interface to prevent direct physical contact between the silicon-containing material and the superalloy substrate.

Abstract: An article comprising a substrate and a plurality of coating units disposed over the substrate is provided. Each coating unit comprises an oxygen-getter layer and a barrier layer. Embodiments of the present invention introduce redundancy to enhance the robustness of a coating system. Multiple protective coating units are disposed over a substrate so that failure of one of the coating units will be far less likely to subject the substrate to direct risk of exposure to the environment. Failure of an outer coating unit merely exposes a pristine protective coating unit, rather than the substrate or a less protective coating layer. In this way, embodiments of the present invention drastically reduce reliance on the performance of one particular coating layer, promoting a more robust and reliable system.

Abstract: Articles for use in a high temperature environment, and methods for protecting articles in such environments, are provided. The article comprises a substrate comprising silicon; a bondcoat comprising silicon, disposed over the substrate; an intermediate barrier disposed over the bondcoat, the barrier comprising at least one layer, wherein the at least one layer comprises a rare-earth silicate and is substantially free of mullite; and a topcoat disposed over the intermediate barrier, the topcoat comprising a rare-earth monosilicate. The method comprises providing a substrate, the substrate comprising silicon; disposing a bondcoat comprising silicon over the substrate; disposing an intermediate barrier over the bondcoat, the barrier comprising at least one layer, wherein the at least one layer comprises a rare-earth silicate and is substantially free of mullite; and disposing a topcoat over the intermediate barrier, the topcoat comprising a rare-earth monosilicate.

Abstract: A material and an article comprising the material are presented. The material comprises a plurality of structural components. The structural components are configured in a series of increasing structural component size classes. The series has a base unit size class and at least one modular size class, and a component of the at least one modular size class comprises a plurality of components of the next smaller size class in the series. The structural components of the base unit size class comprise at least one bulk phase, and the structural components are bonded together at interfaces. Mechanical damage originating within a modular size class structural component is energetically favored to propagate in a distributed fashion among the plurality of structural components contained within the modular size class structural component.

Abstract: A coating for silicon based materials such as those used in high temperature, aqueous environments. An aspect of the invention is directed to an article including a silicon based substrate, a bond coat comprising silicon, and a barrier coat. The barrier coat includes an aluminate such as an alkaline earth metal aluminate or a rare earth aluminate. The barrier coat may be an intermediate coat between the bond coat and a top coat, or it may be the top coat.