SOLVENT-BASED ENVIRONMENTAL BARRIER COATING FOR HIGH TEMPERATURE CERAMIC COMPONENT

PROBLEM TO BE SOLVED: To provide environmental barrier coatings for ceramic components suitable for use in a high temperature steam environment present in a gas turbine engine. SOLUTION: The environmental barrier coatings 12 for high temperature ceramic components comprise: a bond coat layer 14; an optional silica layer 15; and at least one transition layer 16 including: about 85-99 vol.% of the transition layer of a primary transition material comprising a rare earth disilicate or a doped rare earth disilicate; and 1 to about 15 vol.% of the transition layer of a secondary material selected from the group consisting of secondary materials comprising preliminarily defined doped compositions and mixtures thereof. The transition layer is applied to the component as slurry comprising at least an organic solvent, the primary transition material and at least one slurry sintering aid, and wherein a reaction between the slurry sintering aid and the primary transition material results in the transition layer comprising porosity of 0 to about 15 vol.% of the transition layer. COPYRIGHT: (C)2011,JPO&INPIT