Methods of deposition of thick environmental barrier coatings on CMC blade tips
AssigneeGeneral Electric Company
InventorGlen Harold Kirby
Life of this patent
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Abstract
Methods for tape deposition of a sacrificial coating on a CMC substrate are provided. The method comprises: applying a matrix material onto a surface of a film; drying the matrix material to remove the solvent; and transferring the dried matrix material from the film to the CMC substrate. The matrix material comprises a mixture of a rare earth silicate powder, a sintering aid, and a solvent.
Claims20
A method of tape deposition of a sacrificial coating on a CMC substrate having a first rare earth silicate coating thereon, the method comprising:
- applying a matrix material onto a portion of the first rare earth silicate coating, wherein the matrix material comprises a mixture of a rare earth silicate powder, a sintering aid, and a solvent;
- drying the matrix material to remove the solvent;
- transferring the dried matrix material from the film to the CMC substrate to form the sacrificial coating, and
- forming a second rare earth silicate coating on the CMC substrate and the sacrificial coating, wherein the first rare earth silicate coating and the second rare earth silicate coating are merged where the sacrificial coating is not present to encase the sacrificial coating within the first rare earth silicate coating and the second rare earth silicate coating.
A method of tape deposition of a sacrificial coating on a CMC substrate, wherein the CMC substrate is an airfoil having a blade tip, the method comprising:
- applying a matrix material onto a surface of a film, wherein the matrix material comprises a mixture of a rare earth silicate powder, a sintering aid, and a solvent;
- drying the matrix material to remove the solvent;
- and
- transferring the dried matrix material from the film to the blade tip of the airfoil, wherein the tip includes a first rare earth silicate coating on a bond coat, wherein the first rare earth silicate coating comprises at least one rare earth silicate layer, and wherein the dried matrix material is applied onto the first rare earth silicate to form the sacrificial coating;
- forming a second rare earth silicate coating on the sacrificial coating where the sacrificial coating is present at the blade tip and on the first rare earth silicate coating where the sacrificial coating is not present, wherein the second rare earth silicate coating comprises at least one rare earth silicate layer, and wherein the first rare earth silicate coating and the second rare earth silicate coating are merged where the sacrificial coating is not present to surround the sacrificial coating at the blade tip such that the sacrificial coating is completely encased within the first rare earth silicate coating and the second rare earth silicate coating at the blade tip.
Dependencies are inferred from the claim text.