A New Parameter to Predict Cavitation Erosion

In order to avoid or predict cavitation erosion, it is necessary to know resistance of materials against to cavitation impacts. The cavitation impacts, which are larger than certain threshold level, only affect cavitation erosion of materials. In the present paper, existence of the threshold level was revealed experimentally. The threshold level of material is a new parameter to predict the cavitation erosion. Erosion rates for several materials were clarified by using a cavitating jet erosion test, which was new ASTM standard ASTM G134. The cavitation impacts induced by the cavitating jet were measured by means of a special made PVDF transducer, and energy of cavitation impacts was calculated. The threshold levels for several materials were revealed from the relation between the erosion rate and the energy of the cavitation impacts. A method to predict the cavitation erosion quantitatively from the threshold level of material and the measurement of cavitation impacts was proposed.