A Tool to Predict Hot Corrosion of Nickel-based Turbine Disks

Hot Corrosion of turbine engine components has been studied for many years. The underlying mechanisms of Type II Hot Corrosion (Low-Temperature Hot Corrosion) are increasingly well-understood. Nickel-based superalloys have shown strong resistance to high temperature oxidation attack and, of course, excellent high temperature strength. Modern turbine engine designs that seek to achieve better fuel efficiency in part by increasing turbine inlet temperatures are strong candidates for nickel-based superalloy turbine disk materials. As disk temperatures rise, designers must consider the likelihood and effects of hot corrosion.

The research effort focused on the development of probabilistic models for studying the formation and growth of hot corrosion pits as well as on the development of analytical techniques for studying accelerated hot corrosion test samples. The research effort included: (1) experiments that contributed new data to a field of study desperately in need of it; (2) rigorous measurements and data analysis; (3) probabilistic pit initiation and growth models with parameters fit to measured data, and (3) new software implementations. The new data, data analysis, probabilistic models, and software together move the study and engineering practice related to Type II Hot Corrosion significantly forward and set the stage for a transformation Phase III program.