Cavitation erosion testing of austenitic stainless steel (316L) in liquid sodium

Cavitation in hydraulic machinery affects not only the performance of the machines but also shortens the life of components because of the resulting erosion damage. This is all the more important in fast reactors which employ liquid sodium as the coolant because cavitation damage is more intense in sodium than it is in water. It is uneconomical to design hydraulic machinery to avoid inception of cavitation and the only other alternatives are to either improve the hydraulic design to delay cavitation inception or to use either materials with high resistance to cavitation or components hardfaced with materials that have high cavitation resistance. This paper discusses the design and special features of a test facility that uses a vibratory apparatus to study cavitation erosion at high temperature in liquid sodium and presents the initial wear data obtained from the facility on type 316L austentitic stainless steel specimen.