Davies Publishing SPI Practice Test

Piezoelectric materials in ultrasound transducers bend and generate sound when an electric field is applied, or generate an electric signal when they vibrate. Lead zirconate titanate is the dominant ceramic used because it offers strong piezoelectric response and good coupling, which makes it efficient for broad-band imaging. Another piezoelectric material used in some modern transducers is quartz. Quartz is very stable thermally and chemically, with low drift over time, so it’s valued for high‑stability, narrow‑band or reference applications. However, its piezoelectric coupling is weaker than that of PZT, so it isn’t the go‑to choice for most broad-band imaging. The other options aren’t piezoelectric in the context of active transducer elements: tungsten powder with epoxy resin is typically just a backing or damping/matching material, not an active piezoelectric core; rubber lacks piezoelectric properties for transducer use.