This paper considers the influence of the technology to finish and strengthen compressor blade tips made of EP718-ID alloy on the characteristics of the surface quality, surface layer, and bearing capacity. Taking into consideration the special role of the finishing-strengthening treatment in the formation of the quality of the surface layer, various options for blade tip processing were investigated. The blade tips were shaped by high-speed line milling. The finishing-strengthening stage of tip machining included manual polishing and ultrasonic hardening operations with steel balls in various combinations. The basic regularities have been established in the formation of the roughness of tip surfaces, the maximum height of micro-irregularities, the surface microhardness, and the propagation depth of the hardened layer, depending on the combination of finishing-strengthening machining techniques. The results of tests are given for multi-cycle fatigue of blade batches treated according to various variants of the technological process. The efficiency of polishing the surface of the tip after strengthening treatment has been established. To restore the quality characteristics of the surface layer after polishing, it is proposed to perform repeated strengthening treatment. It is shown that the use of double deformation hardening technology with intermediate polishing at the finishing-strengthening stage of blade manufacturing makes it possible to increase the endurance limit from 320 MPa to 400 MPa while increasing durability. Technology for the finishing-strengthening stage of machining blades made from nickel alloys, characterized by significant viscosity, has been devised. It is shown that based on the criteria of minimum labor intensity of machining and maximum endurance of blades, it is effective to use double deformation hardening with steel balls in an ultrasonic field with intermediate polishing.

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The subject of this article is the phenomenon of material destruction during creep, as one of the most dangerous and damaging effects on turbine blades in the conditions of their operation. Considering the strength of the turbine blades of aircraft engines and power plants, note that the mechanism of cracks in the creep process is largely due to the peculiarities of the crystal structures of the blades and the properties of these structures. At this stage of development of world technologies, turbine blades are made by single crystal casting and directional solidification. These types of crystal structures are characterized by the anisotropy of their properties. The reason for the anisotropy of crystals is that the ordered arrangement of atoms, molecules, or ions in the interaction between them and the interatomic distances (as well as some unrelated direct relations, such as polarization or electrical conductivity) differ in different directions. The article pays special attention to the consideration of the creep model of an anisotropic alloy with a monocrystalline structure. The natural way to determine the material parameters of the theoretical material model is to conduct the required number of basic experiments. Numerical modeling using the known creep properties of single crystals is an alternative possibility to determine the parameters of the material. The algorithm described in this article allows us to determine all the average creep properties of a single crystal. The parameters of the described ratios can be obtained either because of direct experiments, or on the basis of micromechanical analysis, as in the case of composite materials. This article considers an example of obtaining some characteristics of the single-crystal alloy ZhS-32 because of the approximation of its creep curves, obtained experimentally. Based on Norton-Bailey's law and using the modern calculation system Maple Release 2021.0, the minimum creep deformation rate and creep constants are determined, and a graph of the creep deformation rate dependence on the material load level is plotted.

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