An article includes a ceramic-based substrate and a barrier layer on the ceramic-based substrate. The barrier layer includes a matrix phase and gettering particles in the matrix phase. The gettering particles with an aspect ratio greater than one are aligned such that a maximum dimension of the gettering particles extends along an axis that is generally parallel to the substrate. The barrier layer includes a dispersion of diffusive particles in the matrix phase. A composite material and a method of applying a barrier layer to a substrate are also disclosed.

A system and a method are provided for inhibiting pyrrhotite-caused damage to concrete structures. The system includes at least one concrete structure, a quantity of migratory corrosion-inhibiting solution, a quantity of concrete reinforcing solution, and a water sealing substance. The concrete structure can be any structure where the concrete aggregate contains pyrrhotite. The quantity of migratory corrosion-inhibiting solution is applied to the concrete structure to prevent further oxidation of pyrrhotite within the concrete structure. The quantity of concrete reinforcing solution is applied to the concrete structure to lower the porosity of the concrete structure and strengthen the overall integrity of the concrete structure. The water sealing substance is applied to the concrete structure to repel water from the concrete structure preventing any further chemical reactions with the pyrrhotite.

A method for repairing a target member including a ceramic matrix composite reinforced by ceramic fiber includes: a removal step of removing at least a part of a surface of the target member; an arrangement step of arranging a green body for repair which includes the ceramic fiber on a portion where the surface is removed in the removal step; an impregnation step of impregnating at least the portion of the target member where the green body for repair is disposed with slurry; and a sintering step of sintering the target member on which the green body for repair is disposed, after the impregnation step.

A method for repairing a target member including a ceramic matrix composite reinforced by ceramic fiber includes: a removal step of removing at least a part of a surface of the target member; an arrangement step of arranging a green body for repair which includes the ceramic fiber on a portion where the surface is removed in the removal step; an impregnation step of impregnating at least the portion of the target member where the green body for repair is disposed with slurry; and a sintering step of sintering the target member on which the green body for repair is disposed, after the impregnation step.

A structural material includes a base material for forming a structure and an ion supplying source provided inside or on a surface of the base material, and the ion supplying source supplies at least one of a cation or an anion that constitutes a sparingly soluble salt having a water-solubility of no greater than a first value at a temperature of an environment where the base material is installed.

A structural material includes a base material for forming a structure and an ion supplying source provided inside or on a surface of the base material, and the ion supplying source supplies at least one of a cation or an anion that constitutes a sparingly soluble salt having a water-solubility of no greater than a first value at a temperature of an environment where the base material is installed.

The disclosure describes braze tape coatings and technique to form articles with differing physical properties in different layers or regions of the article. An example method includes forming a braze tape defining at least one layer that includes a first segment and a second segment. A portion of the second segment in the plane is adjacent to a portion of the first segment in a plane of the layer. The method also includes positioning the braze tape on a surface of a substrate, the plane of the layer of the braze tape being parallel to the surface of the substrate. The method also includes heating the braze tape to melt a constituent of at least one of the first coating material and the second coating material to form a densified coating on the surface of the substrate.

The disclosure describes braze tape coatings and technique to form articles with differing physical properties in different layers or regions of the article. An example method includes forming a braze tape defining at least one layer that includes a first segment and a second segment. A portion of the second segment in the plane is adjacent to a portion of the first segment in a plane of the layer. The method also includes positioning the braze tape on a surface of a substrate, the plane of the layer of the braze tape being parallel to the surface of the substrate. The method also includes heating the braze tape to melt a constituent of at least one of the first coating material and the second coating material to form a densified coating on the surface of the substrate.

An example article may include a component, a substrate including a first ceramic, a joining layer between the component and the substrate, and a joint surface coating between the substrate and the joining layer. The joint surface coating may include a diffusion barrier layer including a second ceramic material, and a compliance layer including at least one of a metal or a metalloid. An example technique may include holding a first joining surface of a coated component adjacent a second joining surface of a second component. The example technique may further include heating at least one of the coated component, the second component, and a braze material, and brazing the coated component by allowing the braze material to flow in a region between the first joining surface and the second joining surface.

A method of producing a ceramic matrix composite including a protective ceramic coating thereon comprises applying a surface slurry onto an outer surface of an impregnated fiber preform. The surface slurry includes particulate ceramic solids dispersed in a flowable preceramic polymer comprising silicon, and the impregnated fiber preform comprises a framework of ceramic fibers loaded with particulate matter. The flowable preceramic polymer is cured, thereby forming on the outer surface a composite layer comprising a cured preceramic polymer with the particulate ceramic solids dispersed therein. The cured preceramic polymer is then pyrolyzed to form a porous ceramic layer comprising silicon carbide, and the impregnated fiber preform and the porous ceramic layer are infiltrated with a molten material comprising silicon. After infiltration, the molten material is cooled to form a ceramic matrix composite body with a protective ceramic coating thereon.