INFLUENCE OF STRUCTURE AND PHASE COMPOSITION OF THE MATERIAL OF STEAM TURBINE BLADES FROM TITANIUM ALLOYS ON THEIR RESISTANCE TO EROSIVE DESTRUCTION

Metallurgy and Materials
Authors:
Krylov Nikolay A. Skotnikova Margarita A. Tsvetkova Galina V. Ivanova Galina V.
Abstract:

Titanium alloys keep a leading position in manufacturing steam turbine blades. The unique combination of high specific strength and fracture toughness, corrosion resistance, polymorphism, a tendency to phase transformations and high resistance to shock loading determined their wide application in power engineering. However, power engineering is still facing a problem of erosion damage of steam turbine blades as a result of a drop impact of vapor particles at speeds of 150...600 m / s. The complication in solving this problem is that it is difficult to establish a link between wear and structural-phase composition of the surface of turbine blades. In this paper, using optical metallography, electron microscopy, ray analysis and X-ray microspectral analysis, we developed a method for studying structural and phase transformations in the material of steam turbine blades of titanium alloy VT6 after technological treatments in different modes. An attempt was made to establish a link between resistance to erosion destruction and structural and phase composition of titanium alloys.