EFFECT OF SLURRY EROSION ON CF8M TURBINE STEEL by Amandeep Kumar
Abstract
Slurry erosion of hydro turbine steel is very common problem in hydro power station where the electric energy is produced by converting the kinetic energy and the pressure energy of water by the turbine blades. When the water comes from hills number of sand particles mix with water and form slurry. When the sand particle size increases then the problem of slurry erosion, in nozzle, gates, agriculture components, pumps, hydraulic components increases. Number of methods has been used for enhancing the life of turbine blades. Protective coatings increase the life of base ma-terial. In this study, slurry erosion performance of CF8M turbine steel has been investigated at 30° angle by changing the parameters i.e stand off distance and slurry concentration. The sand used to perform the experiment was natural sand. By changing the parameter stand of distance and slurry concentration total number of four experiments were performed with uncoated samples and coated samples. Nano coating of TiAlN and AlCrN was selected to protect the material. SEM/EDAX analysis was used to know the morphology of coatings. The most extreme weight reduction occurred when stand of distance was 20mm and the slurry con-centration 20000ppm. But lesser erosion rate showed when the stand of distance was 25mm, slurry concentration was 15000ppm. TiAlN and AlCrN coated samples have more erosion resistance as compared to uncoated samples.
