Ultrasound Effects on Various Oxides and Ceramics: Macro- and Microscopic Analyses

The sonochemistry of a heterogeneous medium such as a liquid/solid powder has been studied for various oxides (lead, manganese, aluminum, rare earth elements, silicon, titanium, and chromium) and ceramics (superconductor and titanium-yttrium compounds). The chemical transformations that occur during ultrasound treatments appear to differ from one material to another. The most important results relate the leaching of Pb 3O 4 which forms the dioxide in dilute acetic acid; and the formation of α-Al 2O 3, and Al(OH) 3 from the η-Al 2O 3 form. It has been established that ultrasound treatments decrease the grain size and smooth small particles.