Characterization of isothermal and cyclic thermal damage of EB-PVD TBCs with the help of the 3D-DIC technique

The thermal barrier coatings (TBCs) are working under complex elevated temperature loading conditions. In the present work, a damage model for the isothermal and cyclic thermal loads was developed to quantify the failure process of the coatings subjected to isothermal and cyclic thermal exposures. Effects of different damage mechanisms, such as thermal exposure, thermal cycling, aluminum migration, and thermal dwell times, were experimentally and computationally studied. The digital image correlation (DIC) technique was introduced to evaluate degradation of TBCs. The complex damage can be quantified with the help of the DIC strain variations. The introduced model provides a general method to estimate the remaining life.