Background. The problem is determined by the real state of energy complexes and the need for a well-founded safe extension of the established resource of energy machines and transport power plants.

Objective. Determination of the effect of non-stationary thermocyclic load on the stress-strain state caused by the change in properties and damage to the material of the surface layers of GTE elements, for the systematic implementation of repair technologies and the extension of the resource.

Methods. Using the methods of physical and numerical modeling, the kinetics of material damage during operation was investigated, taking into account the mutual influence of the stress-strain state and the degraded layer, for which the characteristics of the material of the model alloy were used.

Results. Scientifically based methods of analyzing the kinetics of damage to materials during operation have been developed and the determining role in the resource depletion of structural elements of the processes of degradation of properties, structure and elemental composition of the surface layer of the material in the zones of extreme temperatures and stresses has been shown. It has been established that to estimate the resource of high-temperature elements of GTE structures, it is fundamental to take into account the mutual influence of the degraded surface layer of the material and the stress-strain state.

Conclusions. To make decisions about the current performance of structural elements of power machines, correct assessment of their resource and repairability, it is necessary to take into account the features of damage to structural elements at various stages of operation and the expediency of a step-by-step selection of repair technology.