Design and preparation of triaxial piezoelectric cryogenic vibration sensor based on PZT-7A

A PZT-7A shear-compression composite triaxi-al piezoelectric vibration sensor for low-temperature vibra-tion 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 Hz to 1800 Hz. At room temperature, the voltage sensitivities of the sensors in X, Y, and Z axis were 7.32 mV/g, 8.68 mV/g, and 6.31 mV/g, respectively. When in liquid nitrogen environment, the sensor sensitivity varied 1.78%, 2.65%, and 3.33%, respectively, which satisfy the testing needs in low temperature and can be used for structural health monitoring in low temperature.