Old School piezoelectric transducer

Old School piezoelectric transducer

In addition to the BSPT system, binary and ternary systems are also widely studied for  piezoelectric sensor crystal . Binary system is reported in 2002, PbTiO3 system is due to the stability of the perovskite structure problems, the use of the traditional solid phase method can only get the tetragonal phase structure, and piezoelectric transducer materialscan not achieve the quasi-homogeneous phase boundary, Curie temperature at 484 ℃ or so. it is reported xPbTiO3 system in 2003 . The quasi-homophase boundary is located between 0.36 <x <0.38, the Curie point is about 450 ℃, the room temperature d33 piezo expansion sensor is about 220 pC / N, and the coercive field has a relatively high coercive field of ≈50 kV / cm with remanent polarization ≈38 μC / cm2. In 2004, bTiO3 solid solution was synthesized by solid phase method and sol-gel method, respectively. The phase structure of bTiO3 piezoelectric transducers for wind velocity was studied at different calcination temperatures. The solid solution limit of this system was found to be x = 0.25. In the ternary system, BiScO3 system was reported in 2002. This system has a quasi-homogeneous phase boundary at a PbTiO3 content of 60%, a piezoelectric coefficient is of 210 pC / N and an electromechanical coupling coefficient of piezo ceramic discs wire leads is 68%, the highest Curie temperature is 420 °C and the best figure of merit of 1,000 were obtained. Research system, when y = 0.1,0.2,0.3, the quasi-homophase boundary are located in the vicinity of x = 0.64,0.66,0.7.The grain size is about 1.9 ~ 2.3 μm, far less than 10 μm. Addition of Ba and Sr is considered to significantly inhibit grain growth. Near the quasi-homogeneous phase boundary, the Curie peak of ity pzt material piezo device is depressed and broadened as the Ba and Sr contents increase, while the Curie temperature also moves to the lower temperature. At y = 0.1, 0.2, 0.3, the Curie temperatures are 338, 296 and 246°C, respectively, but the permittivity remains around 1 950 ~ 2 370. At the same time, as the content of Ba and Sr increased, the piezoelectric properties decreased. Compared with 0.36BiScO3-0.64PbTiO3 at y = 0.3, the remanent polarization decreased from 32 μC / cm2 to 24 μC / cm2, and the d33 decreased from 460 pC / N Down to 210 pC / N, the electromechanical coupling coefficient kp is dropped from 0.56 to 0.33. It can be seen that the new perovskite-type ferroelectric xPbTiO3 solid solution system has become a candidate for preparing high-temperature drivers and transducers due to the combination of high curie temperature and high piezoelectricity.