Effect of PbTiO₃ Content Variation on High-power Performance of PMN-PT Single Crystal

Lead magnesium niobate-lead titanate (PMN-PT) piezoelectric single crystals are widely utilized due to their outstanding performance, with varying compositions significantly impacting their properties.While application of PMN-PT in high-power settings is rapidly evolving, material parameters are typically tested under low signal conditions (1 V), and effects of different PT (PbTiO 3 ) contents on the performance of PMN-PT single crystals under high-power conditions remain unclear.This study developed a comprehensive high-power testing platform using the constant voltage method to evaluate performance of PMN-PT single crystals with different PT contents under high-power voltage stimulation.Using crystals sized at 10 mm3 mm0.5 mm as an example, this research explored changes in material parameters.The results exhibit that while trend of the parameter changes under high-power excitation was consistent across different PT contents, degree of the change varied significantly.For instance, a PMN-PT single crystal with 26% (in mol) PT content exhibited a 25% increase in the piezoelectric coefficient 31 d , a 13% increase in the elastic compliance coefficient 11 E s , a 17% increase in the electromechanical coupling coefficient 31 k , and a 73% decrease in the mechanical quality factor m Q when the power reached 7.90 W. As the PT content increased, the PMN-PT materials became more susceptible to temperature influences, significantly reducing the power tolerance and more readily reaching the depolarization temperatures.This led to loss of piezoelectric performance.Based on these findings, a clearer understanding of impact of PT content on performance of PMN-PT single crystals under high-power applications has been established, providing reliable data to support design of sensors or transducers using PMN-PT as the sensitive element.