초록 ▼

A multilayered ceramic topcoat of a thermal barrier coating system is useful for high temperature corrosive applications such as hot section components in gas turbine engines. The ceramic topcoat includes at least two layers, each having generally columnar grain microstructures with different grain

A multilayered ceramic topcoat of a thermal barrier coating system is useful for high temperature corrosive applications such as hot section components in gas turbine engines. The ceramic topcoat includes at least two layers, each having generally columnar grain microstructures with different grain orientation directions. A preferred method of producing the multilayered ceramic topcoat includes positioning a superalloy substrate at a first angled orientation relative to a ceramic vapor cloud in an electron beam physical vapor deposition apparatus for a time sufficient to grow a first ceramic layer. The substrate is then reoriented to a second, different angled orientation for a time sufficient to grow a second ceramic layer. The ceramic layers exhibit columnar microstructures having respective grain orientation directions which are related to the first and second substrate orientations. For uniformly coating a complex contoured surface such as a turbine blade airfoil, the blade can be rotated during coating deposition at each angled orientation.

대표청구항 ▼

[ We claim:] [5.] A coated article comprising:a substrate; anda thermal barrier coating system on the substrate, the thermal barrier coating system comprising:a bond coat on the substrate;an alumina layer on the bond coat; anda ceramic topcoat on the alumina layer, the ceramic topcoat comprising:a f

[ We claim:] [5.] A coated article comprising:a substrate; anda thermal barrier coating system on the substrate, the thermal barrier coating system comprising:a bond coat on the substrate;an alumina layer on the bond coat; anda ceramic topcoat on the alumina layer, the ceramic topcoat comprising:a first ceramic layer having a generally columnar grain micro structure with a first grain orientation direction; anda second ceramic layer disposed thereon having a generally columnar grain microstructure with a different grain orientation direction.