Current Research Status and Future Development of Precipitation Hardening in Piezoceramics

Resonance applications stand as a pivotal application for piezoelectric materials, where mechanical quality factor <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(Q_{m})$</tex> is one of the figures of merit. Piezoelectric hardening is necessary for piezoelectric materials used for resonance applications to suppress domain wall motion and minimize mechanical loss. Precipitation hardening, as a novel piezoelectric hardening technique, was proposed recently for the advantage of pinning domain walls at high vibration velocities. This paper reviews the current development of precipitation hardening in piezoelectric materials, including several examples in which precipitation hardening was successfully implemented, the effect of precipitates on domain wall contribution to electrostrain, and the static precipitate-domain wall interaction. The paper points out the current problems in precipitation hardening and the future research directions for the development of precipitation hardening in piezoelectric materials.