Multiple damage types on carbon steel and silica glass during ultrasonic cavitation erosion

After 15 min ultrasonic cavitation, the cavitation damages on mild carbon steel (Q235) and silica glass were distinguished from each other due to their different physical properties and failure modes. Q235 steel usually suffered plastic deformation under cavitation and had distinctively distributed pits on the surface due to its good toughness, which looked like craters with sunken center and raised smooth margin. While the damage on silica glass surface was irregular with sharp edges, which was resulted from the good hardness and brittle property of glass. The cavitation erosion of silica glass began with nano scaled cavities, and expanded through cracks on the free surface around cavities, then finally ended with large-area collapse of material. Additionally, simplified numerical models have been calculated to discuss the formative factor of multiple damage types.