Abstract: A gas turbine engine article includes a silicon-containing ceramic substrate and an environmental barrier coating (EBC) system disposed on the substrate. The EBC system includes, from the substrate, a dense bond coat layer, a porous bond coat layer, and a topcoat layer in contact with the porous bond coat layer. The dense bond coat layer and the porous bond coat layer each include a silica matrix and oxygen-scavenging gas-evolution particles dispersed through the silica matrix. The porous bond coat layer includes engineered pores.

Abstract: An article includes a ceramic-based substrate and a barrier layer on the ceramic-based substrate. The barrier layer includes a matrix phase and a network of gettering particles in the matrix phase. The gettering particles have an average maximum dimension between about 30 and 70 microns. The gettering particles have maximum dimensions that range from about 1 to 100 microns, and a dispersion of barium-magnesium alumino-silicate particles in the matrix phase. A composite material and a method of applying a barrier layer to a substrate are also disclosed.

Abstract: 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.

Abstract: A gas turbine engine article includes a silicon-containing ceramic substrate and an environmental barrier coating (EBC) system disposed on the substrate. The EBC system includes, from the substrate, a dense bond coat layer, a porous bond coat layer, and a topcoat layer in contact with the porous bond coat layer. The dense bond coat layer and the porous bond coat layer each include a silica matrix and oxygen-scavenging gas-evolution particles dispersed through the silica matrix. The porous bond coat layer includes engineered pores.

Abstract: An article includes a ceramic-based substrate and a barrier layer on the ceramic-based substrate. The barrier layer includes a matrix phase and a network of gettering particles in the matrix phase. The gettering particles have an average maximum dimension between about 30 and 70 microns. The gettering particles have maximum dimensions that range from about 1 to 100 microns, and a dispersion of barium-magnesium alumino-silicate particles in the matrix phase. A composite material and a method of applying a barrier layer to a substrate are also disclosed.

Abstract: 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.

Abstract: A gas turbine engine article includes a substrate and an environmental barrier coating (EBC) system disposed on the substrate. The EBC system includes, from the substrate, a dense bond coat layer, a porous bond coat layer, and a topcoat layer in contact with the porous bond coat layer at an interface. The porous bond coat layer includes a matrix, oxygen-scavenging gas-evolution particles dispersed through the matrix, and engineered buffer pores. The oxygen-scavenging gas-evolution particles react with oxygen and generate a gaseous byproduct that diffuses through the interface to escape the EBC system. The engineered buffer pores buffer diffusion of gaseous byproduct to the interface by retaining at least a portion of the gaseous byproduct.

Abstract: A method of making an ceramic article according to an exemplary embodiment of this disclosure, among other possible things includes arranging fiber plies into a preform, inserting one or more sacrificial springs to the preform, infiltrating the preform with a matrix material to form an article, and thermally degrading the one or more sacrificial springs to form cooling holes. A ceramic article and a gas turbine engine component are also disclosed.

Abstract: A method of making an ceramic article according to an exemplary embodiment of this disclosure, among other possible things includes arranging fiber plies into a preform, inserting one or more sacrificial springs to the preform, infiltrating the preform with a matrix material to form an article, and thermally degrading the one or more sacrificial springs to form cooling holes. A ceramic article and a gas turbine engine component are also disclosed.

Abstract: 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.

Abstract: An article includes a ceramic-based substrate and a barrier layer on the ceramic-based substrate. The barrier layer includes a matrix phase and a network of gettering particles in the matrix phase. The gettering particles have an average maximum dimension between about 30 and 70 microns. The gettering particles have maximum dimensions that range from about 1 to 100 microns, and a dispersion of barium-magnesium alumino-silicate particles in the matrix phase. A composite material and a method of applying a barrier layer to a substrate are also disclosed.

Abstract: A method of making an ceramic article according to an exemplary embodiment of this disclosure, among other possible things includes arranging fiber plies into a preform, inserting one or more sacrificial springs to the preform, infiltrating the preform with a matrix material to form an article, and thermally degrading the one or more sacrificial springs to form cooling holes. A ceramic article and a gas turbine engine component are also disclosed.

Abstract: A gas turbine engine article includes a substrate and an environmental barrier coating (EBC) system disposed on the substrate. The EBC system includes, from the substrate, a dense bond coat layer, a porous bond coat layer, and a topcoat layer in contact with the porous bond coat layer at an interface. The porous bond coat layer includes a matrix, oxygen-scavenging gas-evolution particles dispersed through the matrix, and engineered buffer pores. The oxygen-scavenging gas-evolution particles react with oxygen and generate a gaseous byproduct that diffuses through the interface to escape the EBC system. The engineered buffer pores buffer diffusion of gaseous byproduct to the interface by retaining at least a portion of the gaseous byproduct.

Abstract: An article includes a ceramic-based substrate and a barrier layer on the ceramic-based substrate. The barrier layer includes a matrix of SiO2 and a dispersion of silicon oxycarbide particles in the matrix. The silicon oxycarbide particles have Si, O, and C in a covalently bonded network, and a dispersion of barium-magnesium alumino-silicate particles in the matrix. The barium-magnesium alumino-silicate particles have an average maximum dimension that is between about 10-40% of an average maximum dimension of the silicon oxycarbide particles. A composite material and a method of applying a barrier layer to a substrate are also disclosed.

Abstract: A method of making a ceramic matrix composite is disclosed. According to the method, a first preform comprising fibers is formed, and a second preform including a helical surface portion is inserted into the first preform. The first preform with the inserted second preform is infiltrated with a matrix material comprising a ceramic to form the ceramic matrix composite. A ceramic matrix composite is also disclosed. The ceramic matrix composite includes a first portion including a matrix comprising a ceramic, and a reinforcement including fibers derived from the first preform in the matrix. A second portion including a helical surface portion interface with the first portion is disposed within the first portion.