Damage of an Ultrasonic-Waveguide Surface during Cavitation Accompanied by Sonoluminescence

The surface of a titanium (VT1-0) waveguide, which exhibits the sonoluminescence effect, is analyzed. The effect of sonoluminescence on the waveguide induces the formation of a series of cavities on its surface. Temperatures at the waveguide surface have been estimated, which makes it possible to assess the processes occurring upon sonoluminescence. If the effect observed is a high-temperature phenomenon, traces of metal melting are expected to be found on the waveguide surface. Analysis of the titanium waveguide shows that the observed surface destruction is due to mechanical impact and the absence of visible melting traces is likely to indicate that high temperatures are not reached.