Ultrasonic and piezoelectric properties of the BT-LMT ceramic system

摘要

Ultrasonic and piezoelectric studies of lead free ceramic system structures of (1-x)BaTiO_3-xLa(Mg_(1/2)Ti_(1/2))O_3 (BT-LMT) are presented in this contribution. It was shown, that such materials with x - 0.025, 0.05,0.075 and 0.1 LMT content undergo phase transitions and exhibit piezoelectric effect in the low temperature phases. Anomalies of ultrasonic velocity and attenuation at phase transitions have been observed in these materials. Measurements of temperature dependencies of ultrasonic velocity and attenuation revealed anomalies related to phase transitions in these materials. It was shown that, at room temperature and under dc bias electric field, these ceramics behave as a piezoelectrics because of electrostriction.