Piezoelectric properties of piezoelectric transducer

The piezoelectric properties are with the increasing of Mn content, low frequency piezoelectric transduceris doping kp and Qm variation. With the increase of Mn doping, kp and d33 of piezoelectric actuator vibration control have been decreased, while Qm first increased and then decreased. The possible reason is that Mn substitutes the B site in the crystal structure of ABO3 type.Perovskite generates certain oxygen vacancies and exhibits typical acceptor doping characteristics, which leads to decrease the increasing of kp and d33,piezoelectric plate crystalinfluences grain size in a certain range, large grains can promote the piezoelectricity of piezoelectric ceramics, and larger grains can reduce the grain boundaries generated during the polarization process. Stress and Qm is increasing, so that tan W is down. However, the increasing of the piezo sphere transducer will lead to the increase of the size of the 90°ferroelectric domain, and the polarization rotation will not be easy and the X will decrease. At the same time, the grain size is too large, the inter granular void will increase, the grain will not bond with each other and the actual density deviates seriously .The theoretical density of piezoelectric sensor price  leads to decrease in mechanical strength, a decrease in Qm, and a decrease in the piezoelectric activity of the sample, so the grain size of the piezoelectric ceramic cannot be too large. When Mn is doping amount r> 0.2%, the grain rapidly grows, so that kp and d33 fall faster, but Qm of PZT material piezo plates does not rise but decreases, piezoelectric activity decreases; when Mn doping r> 0.2% , The changes of kp, d33 and Qm may be mainly related to the smaller mechanical strength and inhomogeneity distribution of the grains. In summary, when the Mn is doping ,0.2% of the sample has good piezoelectric properties.