Kinetics of Destruction of Armco Iron Under Cavitation Load.

Specimens of normalized Armco iron were tested in special cavitation tunnels for weight loss and then for destruction by cavitation erosion. During the incubation period, the results were affected significantly by the thermal pretreatment of the iron. The damage during continued exposure to imploding cavitation bubbles is attributed mainly to step formation around grain boundaries, which is explained as the effect of superimposition of a high frequency load on quasistatic stress as the result of the anisotropic deformation behavior of the individual grains. In connection with destruction mechanisms inside the individual grains, craters encountered propagating fast in depth. The results of the investigation point the way toward methods for increasing the cavitation drag.