Acoustic and Electrical Properties of Piezoelectric Materials for High-Temperature Sensing Applications

摘要

Sensing applications at temperatures above 500 °C have motivated research on a number of innovative single-crystalline piezoelectric materials that are compositionally and structurally stable at these temperatures. These materials include ordered and disordered crystals in the langasite family, gallium orthophosphate, rare-earth calcium oxyborates, and crystals with the structure of melilite. In this review, measurements and analysis of the properties of these materials relevant to the operation of piezoelectric acoustic sensors at elevated temperatures are summarized, with a primary focus on acoustic loss arising from temperature-dependent electrical conductivity.