Damage evolution during thermo-mechanical fatigue of a coated monocrystalline nickel-base superalloy

To prevent hot gas corrosion nickel-base turbine blades used in today’s jet engines, they are protected with so called Pt-modified β-NiAl coatings which are also subjected to thermo-mechanical loading during service. The effects of thermo-mechanical fatigue (TMF) loading on the coating as well as TMF life are the subjects of this paper. Microstructural investigations before, during and after thermo-mechanical fatigue treatment using atomic force and scanning electron microscopy on the monocrystalline nickel-base alloy PWA1484 were conducted to reveal the dominating failure mechanisms.