| abstract |
Environmental barrier coatings for high temperature ceramic components including a bond coat layer; an optional silica layer; and at least one transition layer including: from about 85% to about 100% by volume of the transition layer of a primary transition material including a rare earth disilicate, or a doped rare earth disilicate; and from 0% to about 15% by volume of the transition layer of a secondary material selected from Fe 2 O 3 , iron silicates, rare earth iron oxides, Al 2 O 3 , mullite, rare earth aluminates, rare earth aluminosilicates, TiO 2 , rare earth titanates, Ga 2 O 3 , rare earth gallates, NiO, nickel silicates, rare earth nickel oxides, Lnb metals, Lnb 2 O 3 , Lnb 2 Si 2 O 7 , Lnb 2 SiO 5 , borosilicate glass, alkaline earth silicates, alkaline earth rare earth oxides, alkaline earth rare earth silicates, and mixtures thereof; where the transition layer is applied to the component as a slurry including at least an organic solvent, the primary transition material and at least one slurry sintering aid, and where a reaction between the slurry sintering aid and the primary transition material results in the transition layer having a porosity of from 0% to about 15% by volume of the transition layer. |