Cavitation Erosion Behaviors of a Nickel-Free High-Nitrogen Stainless Steel

The cavitation erosion and corrosion characteristic of a nickel-free high-nitrogen stainless steel (HNSS) in distilled water and 0.5 mol/L HCl solution were investigated by conducting gravimetric and electrochemical measurements, including corrosion potential, polarization curves and electrochemical impedance spectroscopy, and the eroded/corroded surface was observed by scanning electron microscopy. The results revealed that the dominant contribution to cavitation erosion damage was the mechanical degradation process, even though the corrosion rate of HNSS was accelerated in 0.5 mol/L HCl solution. Corrosion and mechanical degradation worked synergistically and promoted crack initiation and propagation under cavitation erosion.