Abstract Since the record of aircraft engine failures has deteriorated in the recent years, the issues of turbine blade service life and those of structural stability of Ni-based superalloys have been treated worldwide. While in service the blades of gas turbines are exposed to a number of degrading influences, particularly to the high-temperature corrosion, fatigue processes and creep. In the periods of short-time overloading, e.g. during takeoffs, landings, or when experiencing other performance irregularities, the microstructure of the wheels undergoes irreversible changes in material and its properties induced by temperature and stress peaks. This paper aims to study the microstructure of turbine wheels made of INCONEL 713 LC, a Ni-based superalloy, and observed to develop blade damages throughout the test operation.