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The article is a review of the literature data related to the wear of steam turbine blades. The literature review have found that the main causes of blade damage are erosion, corrosion, and the occurrence of elevated temperatures inside the turbine, which cause, among other things, blade elongation, deformation, and cracks due to rapid temperature changes (thermal shock). A review of the literature has shown that blades are a subject to erosion resulting from operating conditions in which the blades strike water droplets formed from steam or from the injection of cooling condensate in the zone of the last stage of the low-pressure part of the turbine. Erosion occurs mainly at the inlet and outlet edges of the blades, causing imbalance (different blade wear in one rotor stage) in addition to reducing turbine efficiency. Erosion can also cause an increase in stresses that can lead to serious damage not only to the blades, but also to other turbine components. Steam turbine blades are also exposed to aggressive working environment (chlorides, sulfates, and alkali metal silicates from steam) as a result of which uniform and also pitting corrosion can occur on the blades. The article also analyses the effect of operating conditions on the damage that occurs, as well as the literature on predicting turbine blade life.Keywords: steam turbines, erosion, corrosion, wear, blade, surface top layer

This paper presents the results of testing surfacings produced by LMD (Laser MetalDeposition) laser deposition technology at different laser beam parameters. On the surface layer ofrectangular-shaped samples made of 1.4923 steel, multiwall surfacing was produced from HS6-5-2cpowder with different degrees of coverage. As part of the laser deposition verification and testing,surface topography, microstructure and hardness tests were carried out in the deposition zone, heataffectedzone and the zone of the parent material. The surface of the surfacing and the microstructurein cross-section were observed on an optical microscope with fibre-optic image transmission. Hardnessmeasurements were made in the cross-section of the sample using a Vickers FLC-50A hardness tester.Based on the observations, it was found that the obtained surfacings have a regular and repeatableshape. There were no welding defects on the surfaces of the produced surfacings and in the zoneof fusion of the surfacing material with the substrate material. The hardness of the surfacings wasobtained in the range of 500-700 HV0.1. The produced surfacings by LMD technology were subjectedto erosion resistance tests, which showed significantly higher (about 5. times) resistance to erosionwear of the produced surface layers (surfacings based on HS6-5-2c powder) in comparison with thesubstrate material, i.e. steel 1.4923.Keywords: steel 1.4923, HS6-5-2c alloy powder, LMD laser deposition, surface layer, depositiongeometry, chemical composition, microstructure, hardness, erosion