Investigation of the microstructural and mechanical property changes of NiAl coated Ni-based superalloys during high temperature exposure

The present work focused on the determination of the mechanical behavior of aluminized Ni-based superalloys with respect to their microstructural degradation during high temperature exposure. For this purpose, a mechanical model concept was developed, which utilized Al-concentration as the major influential parameter. Mechanical properties were determined using experimental methods and were correlated with the Al-content. These experimental results were then conveyed into a software tool, which was used to determine the load-bearing capability of the coated components below and above the ductile to brittle transition temperature (DBTT) of the coating as a function of exposure duration, temperature, component and coating thickness as well as the Al-concentration in the as-deposited coating.