Abstract
Two-stage cavitation erosion tests were performed using carbon steel S15C with a cavitating jet apparatus in seawater and tap water. The mass loss of carbon steel S15C by cavitation erosion is reduced remarkably when the test solution is changed to tap water from seawater. However, the mass loss rate that occurs when the experimental environment is changed to seawater from tap water is markedly higher because of corrosive action and mechanical disruption, and their synergistic effects. Changes in the environment demand consideration of the fluid mechanics because mass loss increases remarkably when the environment is changed repeatedly to seawater from tap water.