Post-operation state and extension of service life of compressor blades of the gas-turbine power plant GTE-45-3

Gas turbine engine compressor blades are the most essential parts among all the units of gas turbine power plants. They are made of chromium stainless steels. Erosive and corrosive wear of working surfaces as well as thermal stress fatigue are the main types of damage of compressor blades after long-term use.  The aim of this work was to develop methods of recovering the serviceability of the material of the power plant ГТЭ-45-3 compressor blades with a view to extending their service life. To examine the post-operation state of compressor blades and the material serviceability the compressor blades of the gas turbine engine power plant ГТЭ-45-3 made of corrosion-resistant steels ЭИ961 (13Х11Н2В2МФ) and 12Х13 were investigated after their service life expired with the total engine hours equal to 50000. To evaluate the serviceability of the blade material an unconventional approach and know-how were used. The results of analysis of the microstructure of corrosion-resistant steels as well as their physical and mechanical properties are presented in the paper. A process of material serviceability recovery is developed with a view to extending the service life of compressor blades. The process includes the following sequence of operations: machining aimed at removing corrosion and mechanical defects, argon-arc welding that  restores the geometry of the rotor blades, thermal tempering for removing residual stress.