A coating according to an exemplary embodiment of this disclosure, among other possible things includes a bond coat including gettering particles and diffusive particles dispersed in a matrix; a top coat disposed over the bond coat, the top coat includes metal silicate particles; and an intermediate layer between the bond coat and the top coat. The intermediate layer includes hafnium silicate particles and matrix. A concentration of metal silicate in the intermediate layer is less than a concentration of metal silicate in the top coat. An article is also disclosed.

Disclosed herein are methods for functionalizing the surface of a biomedical implant. The biomedical implant may be a zirconia-toughened alumina implant surface functionalized with silicon nitride powder for promoting osteogenesis.

Disclosed herein are methods for functionalizing the surface of a biomedical implant. The biomedical implant may be a zirconia-toughened alumina implant surface functionalized with silicon nitride powder for promoting osteogenesis.

Provided are a coating structure, a turbine part having the same, and a method for manufacturing the coating structure. The coating structure is provided on a surface of a base portion including a ceramic matrix composite. The coating structure is layered on the surface of the base portion, and includes a bond coat layer formed of a rare-earth silicate and a top coat layer layered on the bond coat layer. The residual stress present in the bond coat layer is compressive residual stress. The oxygen permeability coefficient of the bond coat layer is no greater than 10.sup.−9 kg.Math.m.sup.−1.Math.s.sup.−1 at a temperature of not lower than 1200° C. and a higher oxygen partial pressure of not less than 0.02 MPa. The bond coat layer may contain carbonitride particles or carbonitride whiskers.

Provided are a coating structure, a turbine part having the same, and a method for manufacturing the coating structure. The coating structure is provided on a surface of a base portion including a ceramic matrix composite. The coating structure is layered on the surface of the base portion, and includes a bond coat layer formed of a rare-earth silicate and a top coat layer layered on the bond coat layer. The residual stress present in the bond coat layer is compressive residual stress. The oxygen permeability coefficient of the bond coat layer is no greater than 10.sup.−9 kg.Math.m.sup.−1.Math.s.sup.−1 at a temperature of not lower than 1200° C. and a higher oxygen partial pressure of not less than 0.02 MPa. The bond coat layer may contain carbonitride particles or carbonitride whiskers.

The present invention relates to a method and to a crucible for producing particle-free and nitrogen-free silicon ingots by means of targeted solidification, in which method a crucible is provided, the inner surface of the crucible having a coating containing Si.sub.xN.sub.y over its full surface or at least in regions, which coating is coated with a protective layer containing SiO.sub.x in order to reduce or prevent the introduction of nitrogen and Si.sub.xN.sub.y particles into the silicon. The invention also relates to a silicon ingot, which is virtually free from nitrogen or Si.sub.xN.sub.y particles.

The present invention relates to a method and to a crucible for producing particle-free and nitrogen-free silicon ingots by means of targeted solidification, in which method a crucible is provided, the inner surface of the crucible having a coating containing Si.sub.xN.sub.y over its full surface or at least in regions, which coating is coated with a protective layer containing SiO.sub.x in order to reduce or prevent the introduction of nitrogen and Si.sub.xN.sub.y particles into the silicon. The invention also relates to a silicon ingot, which is virtually free from nitrogen or Si.sub.xN.sub.y particles.

A method includes forming a crystallized metal carbide undercoat on a surface of a carbon-carbon composite substrate. The method further includes forming an overcoat on a surface of the undercoat. The overcoat includes a plurality of crystallized ultra-high melting point overcoat layers. Each overcoat layer is sequentially formed by applying a mixture to a surface of an underlying layer and heating the mixture. The mixture includes a plurality of ultra-high melting point refractory ceramic particles and a pre-ceramic polymer. The mixture is heated to a heat treatment temperature to pyrolyze the pre-ceramic polymer and form the overcoat layer in an inert atmosphere or under vacuum. As a result, the overcoat layer includes a crystallized ultra-high melting point polymer-derived ceramic matrix that includes the plurality of ultra-high melting point refractory ceramic particles.

A method includes forming a crystallized metal carbide undercoat on a surface of a carbon-carbon composite substrate. The method further includes forming an overcoat on a surface of the undercoat. The overcoat includes a plurality of crystallized ultra-high melting point overcoat layers. Each overcoat layer is sequentially formed by applying a mixture to a surface of an underlying layer and heating the mixture. The mixture includes a plurality of ultra-high melting point refractory ceramic particles and a pre-ceramic polymer. The mixture is heated to a heat treatment temperature to pyrolyze the pre-ceramic polymer and form the overcoat layer in an inert atmosphere or under vacuum. As a result, the overcoat layer includes a crystallized ultra-high melting point polymer-derived ceramic matrix that includes the plurality of ultra-high melting point refractory ceramic particles.

Methods for repairing composite component voids are provided. For example, one method comprises locating a void in a composite component and subjecting the composite component to a process for repair. The process for repair includes creating a flow path through the void, applying a filler material to the composite component at the flow path, and processing the composite component having the filler material. In some embodiments, the flow path has a first opening on a first side of the composite component and a second opening on a second, opposite side of the composite component. In other embodiments, at least one portion of the flow path extends at a first angle with respect to a lateral direction defined by the CMC component, and at least another portion extends at a second angle with respect to the lateral direction.