High-temperature vibration damping of thermal barrier coating materials

The damping behavior of several materials used in current thermal barrier coating systems are reported from room temperature up to 1200 °C. The effect of long-term aging at 1150 °C on the damping behavior of a PWA-1484 single crystal superalloy is presented as well as the effect of a platinum-modified diffusion nickel aluminide bond-coat and an electron-beam evaporated, yttria-stabilized zirconia (EB-YSZ) thermal barrier coating. The nickel aluminide bond coat is shown to enhance the damping of the superalloys at all temperatures while the EB-YSZ shows a damping peak at ∼ 220 °C. The damping behavior of two top-coat materials, tetragonal-prime YSZ and gadolinium zirconate is compared. The latter exhibits a damping peak at a higher temperature (∼ 350 °C) than zirconia giving it the potential of being used as a damping coating for compressor blade.