Abstract
	Inconel 713 LC belongs to the cast poly-crystalline nickel super-alloys which are used for the production of circulating wheels of small combustion turbines for supplementary energetic units in aviation industry. In operational conditions of combustion turbines as part of turbo engines, blades of the circulating wheels are stressed in time, temperature and stress variable cycles during the loading procedure. The blades are exposed to a series of degradation factors such as high-temperature corrosion, fatigue processes and creep during the operation.
	The current knowledge obtained through structural analyses of operational impellers does not rely, save for some exceptions, on a sufficiently detailed investigation of structural, chemical and dendriteform non-homogeneity of the above-mentioned material as found after exposure to the operational conditions. Also a comparison study of exposed versus fresh materials is still to be performed.
	The aim of presented work is to study the microstructure of cast nickel-base alloy Inconel 713 LC after testing at the exploitation temperature. The structural changes were studied using light microscopy and transmission electron microscopy (TEM).