Patent ID: 8226362

Claim:
A steam turbine component assembly comprising: an inner housing having a surface exposed to a high temperature operating environment and an opposite surface exposed to a lower temperature operating environment where the temperature difference between the higher and lower temperature environments is at least 200° C.; an outer housing that surrounds the inner housing; and a ceramic thermal barrier coating having a pre selected porosity, thickness or material composition applied to the higher temperature surface effective to control thermal deformation of the inner and outer housings relative to each other, wherein the outer housing completely surrounds the inner housing, wherein the higher temperature operating environment is between 450° C. and 800° C., and wherein the ceramic thermal barrier coating is applied in a steam inflow region of the steam turbine, wherein the ceramic thermal barrier coating is applied to a housing having an intermediate protective layer arranged between the housing and the ceramic thermal barrier coating, the intermediate protective layer comprising the composition of MCrAlX where M is at least one element selected from the group consisting of nickel, cobalt or iron and X is yttrium or silicon or at least one rare earth element, and wherein the intermediate protective layer consists of: 11.5 wt %-20 wt %, chromium, 0.3 wt %-1.5 wt %, silicon, 0.0 wt %-1.0 wt %, aluminum, and remainder iron.