Comparative results of a study of certain properties of TiN-cladded compressor blades of ÉI-961 steel in the initial state, after a period of service, and after rated tests on an impact testing stand are presented. It is shown that in-service changes in endurance limit, wear resistance, residual macrostresses, microhardness, and TiN lattice parameter can be predicted with reasonable accuracy based on results of impact tests at an acceleration of about 104m/sec2.