Increment of steam turbine blades service life by means of erosion-resistant plasma coating deposition with meso-ordered structure

Abstract

Abstract Main reasons and wear mechanism of steam turbine blades have been examined. Efficient recovery method of steam turbine blades allowing to increase their service life and enhance greatly service life of power units have been suggested. Materials to deposit coating layers have also been selected and deposition technology have been developed. Structure, porosity, micro-hardness, adhesion strength, erosion resistance and heat resistance of deposited coating have been researched. Suggested method can be used both for deposition of a coating on new turbine blades and for recovery of worn surfaces without overhaul of a turbine due to applying of a mobile compact plasma unit of in-house design. Composition of the coating featuring meso-arranged structure during deposition process greatly increases most operational performances of the whole ‘coating – substrate’ system.