Based on the approaches of continual mechanics and computer simulation, a computational methodology for establishing the operational parameters of functionally graded parts depending on the dimensional characteristics of elliptical defects is proposed. For the first time, using spatially non-local models of mechanics and the FEniCS finite element package, a calculation scheme was constructed for determining the contact strength of a material depending on the ratio of the sizes of the main radii of an elliptical defect in a structure. On the example of locomotive wheel tyres, it is shown that the most dangerous for operation are elliptical “needle-shaped” hubs with a ratio of the radii of the main axes of more than 40. They can also be a source for the development of “crack-type defects” during the operation of products. The established connection between the change in the properties of railway wheels under the action of loads and the characteristics of stress concentrators indicates that the shape of the concentrator is a more dangerous factor than its volume, and allows you to determine ways to control the operational parameters of parts with the presence of stress concentrators by surface engineering methods.

The manufacture of rolling stock components with a given life cycle based on the computerization of all design and production stages is the most promising way to increase the energy efficiency of its operation. The implementation of this approach requires the expansion of the use of technologies that provide parts with a high level of mechanical and operational properties. The state of the surface layers is important in the formation of the reliability parameters of high-loaded parts. The principles of using system approaches for the physical justification of the choice of the optimal modes of engineering grain boundaries depending on the operating conditions of products are presented. New approaches and algorithms have been created that allow quantitative and qualitative studies of the effect of technological treatments and the chemical composition of polycrystals on the strength of grain boundaries and the processes of softening of the boundary zones. Using the developed techniques, the ways to control the energy state of the internal interfaces by doping, microalloying and heat treatment were determined to increase the resistance to brittle fracture and wear of the steels used in the manufacture and repair of rolling stock.