Research progress in fresnoite high-temperature piezoelectric crystal and its sensors

Piezoelectric materials， as important functional materials， have been widely used in various fields of the national economy for the preparation of structural health detection devices. With the development of modern industrial technology， especially aerospace， nuclear energy， and intelligent manufacturing， various high-temperature conditions have put forward higher requirements for the performance of piezoelectric materials. Therefore， the development of high-temperature piezoelectric materials with excellent comprehensive performance and their application in sensor devices with higher service temperatures have received widespread attention from researchers. Fresnoite （Ba2TiSi2O8， BTS） crystal is a kind of promising piezoelectric material for high-temperature sensing applications due to its high electrical resistivity， low dielectric loss， and excellent piezoelectric properties. The preparation process of BTS crystal by Czochralski method， characterization of single crystal electro-elastic properties， phase transition regulation， and the research progress of surface acoustic wave sensors and high-temperature vibration sensors based on BTS piezoelectric crystal were introduced in this paper. Finally， the research and development of new high-temperature piezoelectric crystals and their sensors were summarized and presented.