Design and Preparation of Triaxial Piezoelectric Cryogenic Vibration Sensor Based on PZT-7A

A PZT-7A shear-compression composite triaxial piezoelectric vibration sensor for low-temperature vibration sensing was designed and fabricated. The vibration sensor was first modeled dynamically, and then sensor simulation, preparation of PZT-7A ceramics, assembly of the sensor, and construction of the experimental test system were carried out. The output of the sensor is stable in the frequency range of 200-1800 Hz. At room temperature, the voltage sensitivities of the sensors in the X-, Y-, and Z-axes were 7.32, 8.68, and 6.31 mV/g, respectively. When in a liquid nitrogen environment, the sensor sensitivity varied by 1.78%, 2.65%, and 3.33%, respectively, which satisfy the testing needs in low temperatures and can be used for structural health monitoring in low temperatures.