FAQ: Please, what is the material used in the piezoceramics’ flat surfaces? I bought a piezo ring that seems to have a protective white color film over the silver electrode and I do not know what that is. Ceramics of all brands have a protective white material, but I do not know the material. Should I remove it with a very fine 5000 sandpaper? Mr. P.R.
Piezo ceramics electrodes: the silver oxide is white while metallic silver is metal shiny.
The white material is silver oxide that is formed during the silver painting firing. Removing this thin oxide layer will improve mechanical coupling, electrical and heat conductivity, besides reducing roughness, which will improve to the converter performance. However, be careful not to remove the metallic silver paint along with the silver oxide. Use a 5000 sandpaper or ordinary sulfite paper over a flat granite plate. You should remove the silver oxide without removing the metallic silver paint or degrading the parallelism and flatness.
Learn more about preventive maintenance of ultrasonic acoustic stacks.