Effects of alloy composition on the performance of yttria stabilized zirconia - Thermal barrier coatings

Thermal barrier coatings (TBCs) provide an alloy surface temperature reduct ion when applied to turbine component surfaces. Thermal barrier coatings ca n be used as a tool for the designer to augment the pou er and/or enhance t he efficiency of gas turbine engines. TBCs have been used successfully in t he aerospace industry for many years, with only limited use for industrial gas turbine applications, Industrial gas turbines operate for substantially longer cycles and time between overhauls, and thus endurance becomes a cri tical factor. There are many factors that affect the life of a TBC includin g the composition and microstructure of the hose alloy and bond coating. Al loys such cls Mar-M 247, CMSX-4, and CMSX-10 are,materials used for high te mperature turbine environments. and usually require protective and/or therm al barrier coatings for increased performance. Elements such as hafnium, rh enium, and yttrium have shown considerable improvements in the strength of these alloys. However, these elements may result in varying effects on the coatability find environmental performance of these alloys. This paper disc usses the effects of these elements on the performance of thermal barrier c oatings.