CMAS RESISTANT THERMAL BARRIER COATINGS

摘要

The present application provides Calcia-Magnesia-Alumina-Silica (CMAS) (or molten silicate) resistant thermal barrier coatings (TBC). The coatings include elongate growth domains of non-equiaxed, randomly arranged overlapping grains or splats. The elongate growth domains include overlapping individual, randomly distributed splats of tough and soft phases. In some embodiments, the elongate growth domains are formed via air plasma spray. In some embodiments, the tough phases are at least partially stabilized zirconia and/or hafnia compositions, and the soft phases are CMAS (or molten silicate) reactive or resistant compositions. Within each elongate growth domain, the mixture of the tough and soft phases act together to limit penetration of CMAS and also provide sufficient domain toughness to minimize cracking forces produced during crystallization of infiltrated CMAS. The soft phases may react with the CMAS and increase its melting point, increase its viscosity, and reduce the destabilization of the tough phases.

主权项

1. A thermal barrier coating comprising:
a plurality of elongate material growth domains defined between domain boundaries, wherein the domains have an intra-domain density of at least about 75%, and comprise individual, randomly distributed splats of tough and soft phases stacked throughout the growth domains, and wherein the tough phases are at least one of partially stabilized zirconia compositions and partially stabilized hafnia compositions, and the soft phases are at least one of CMAS reactive compositions and CMAS resistant compositions.