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.

A method includes depositing a porous silicon coat on a substrate to form a bulk phase of a bond coat and introducing a reactive gas into pores of the porous silicon coat. The reactive gas reacts with silicon adjacent the pores of the porous silicon coat to form a ceramic phase of the bond coat comprising a silicon-based ceramic and reduce porosity of the porous silicon coat. A temperature of the reactive gas is greater than about 1000° C.

Disclosed is a multi-phase abradable coating including a ceramic matrix and a dislocator phase.

The thermal barrier coating includes reactive gadolinia in its microstructures and the embedded gadolinia effectively reacts with CMAS contaminant reducing the damage from CMAS. Moreover, a method to produce a CMAS resistant thermal barrier coating can include a post-treatment to the thermal barrier coating with the reactive gadolinia suspension in sol-gel state.

Methods for preparing an environmental barrier coating and the resulting coating are provided. The methods and products include the incorporation of a continuous ceramic inner layer and a segmented ceramic outer layer on a CMC component. The segmented ceramic outer layer may be formed by thermal spray techniques. The coating is more stable at higher temperatures and provides for a longer lifetime of the coated component.

A blade outer air seal assembly includes a carrier that has a slot and a hole that extends into the slot. A blade outer air seal has a plurality of segments that extend circumferentially about an axis and mounted in the carrier. At least one of the plurality of segments has a base portion and a first wall that extends axially and radially outwardly from the base portion. The first wall has an aperture. A pin extends through the hole and the aperture.

Methods for preparing an environmental barrier coating and the resulting coating are provided. The methods and products include the incorporation of a continuous ceramic inner layer and a segmented ceramic outer layer on a CMC component. The segmented ceramic outer layer may be formed by thermal spray techniques. The coating is more stable at higher temperatures and provides for a longer lifetime of the coated component.

A coated member includes a heat-shielding coating layer made of a zirconia-dispersed silicate in which ytterbia-stabilized zirconia is precipitated as a dispersed phase in a matrix phase which is any one of a rare earth disilicate, a rare earth monosilicate, and a mixed phase of the rare earth disilicate and the rare earth monosilicate. The rare earth disilicate is a (Y.sub.1-a[Ln.sub.1].sub.a).sub.2Si.sub.2O.sub.7 solid solution wherein Ln.sub.1 is any one of Sc, Yb, and Lu, or a (Y.sub.1-c[Ln.sub.2].sub.c).sub.2Si.sub.2O.sub.7 solid solution wherein Ln.sub.2 is any one of Nd, Sm, Eu, and Gd. The rare earth monosilicate is Y.sub.2SiO.sub.5, [Ln.sub.1].sub.2SiO.sub.5, a (Y.sub.1-b[Ln.sub.1]b).sub.2SiO.sub.5 solid solution wherein Ln.sub.1 is any one of Sc, Yb, and Lu, or a (Y.sub.1-d[Ln.sub.2].sub.d).sub.2SiO.sub.5 solid solution wherein Ln.sub.2 is any one of Nd, Sm, Eu, and Gd.

In one example, a method for forming an environmental barrier coating (EBC) on a substrate. The method may include heating the substrate before and/or during deposition of EBC on the substrate using an external burner and/or resistive electrical heating. Additionally, or alternatively, the as-deposited EBC may be heat treated using an external burner and/or resistive electrical heating. In some examples, the techniques of the disclosure are configured to increase or otherwise tailor the amount of crystalline phase in the EBC.

Methods for preparing an environmental barrier coating and the resulting coating are provided. The methods and products include the incorporation of a continuous ceramic inner layer and a segmented ceramic outer layer on a CMC component. The segmented ceramic outer layer may be formed by thermal spray techniques. The coating is more stable at higher temperatures and provides for a longer lifetime of the coated component.