Cracking of nickel superalloys with a high content of ????’-phase remains an unresolved problem, including in technologies for repairing gas turbine engines blades. Laser cladding is a method of material deposition used to repair parts exposed to aggressive environment and surface wear. Cladding parameters have a high influence on cracking susceptibility nickel superalloys. Alloy ZhS32 has a high propensity for hot cracking when exposed to laser radiation. In this work, the study of the structural and phase features of ZhS32 alloy was carried out. A high tendency to form segregation of refractory elements and carbides in the intergranular areas was found. The features of the structure and phase composition of the material for different cladding parameters were studied. The main contribution of technological parameters to the formation of cracks is shown.

Modern methods and technologies for the creation and processing of materials provide great opportunities for research. This work is devoted to the study of the causes of hot cracks, as well as the application of an analytical method for assessing the occurrence of hot cracks in high-temperature nickel alloys ZhS32, ZhS6U, ZhS6K, Rene 80, Rene 41, processed by laser powder cladding. In the course of the work, the process of the influence of a heat source on samples was modeled, an analysis of thermal fields and isotherms was performed, on the basis of which an analytical method was developed for finding the criterion for the pressure drop along the crystallization front in different modes and grades of alloys, to assess the tendency to form hot cracks in high-temperature nickel alloys.

A gas turbine engine is a technological system consisting of a compressor, a combustion chamber, and other modules. All these components are subjected to dynamic and cyclic loads, which lead to fatigue cracks and mechanical damage. The aim of this work is to repair the worn surfaces of a series of DR-59L high-pressure turbine blades by laser powder cladding. A number of technological parameters of laser cladding were tested to obtain a defect-free structure on the witness sample. The metal powder of the cobalt alloy Stellite 21 was used as a filler material. By modeling the process of restoring rotor blades, the operating mode of laser powder cladding was determined. No defects were detected during capillary control of the restored surfaces of the rotor blades. The results of the uniaxial tension test of the restored rotor blades showed increased tensile strength and elongation. With the use of laser powder cladding technology, it was possible to restore the worn surfaces of a series of rotor blades of the DR-59L high-pressure turbine, thereby increasing the life cycle of power plant products.