Abstract
Piezoelectric wafer active sensors (PWAS) have been developed for structure health monitoring (SHM) for years, however, SHM at extreme environments has rarely been attempted due to the low phase transition temperature of common piezoelectric materials. In this paper, new piezoelectric materials-Langasite (LGS) has been selected for a pilot study for structure health monitoring applications. A preliminary study is performed to verify the possibility of developing the LGS high temperature piezoelectric waver active sensors. The E/M impedance method is applied to detect the frequency behavior of the PWAS. Experiments that verify the basic frequency behavior of the LGS PWAS in high temperature environments have been carried out. Further validations are conducted by testing structures attached by LGS PWAS at elevated temperatures. The results, at the first time, show that LGS is ideal to make piezoelectric wafer active sensors for high temperature structure health monitoring applications.
