Experimentation and simulation study of electromechanical response characteristics of a 2-2 type cement-based piezoelectric composite sensor

In the manuscript, the piezoelectric functional element was prepared by slicing and adding method using piezoelectric ceramic PZT-5H and ordinary silicate cement 42.5 was as base materials, and then a 2-2 type cement-based piezoelectric composite sensor was prepared by an encapsulated epoxy resin. The experimental and simulation analysis was carried out to obtain the quasi-static linear sensitivity of the electromechanical response of the sample under conditions of compressive loading. The development process of the sample from local failure to overall fragmentation was observed using a high-speed camera. Found that the electrical nonlinear threshold of 35 MPa appeared before the mechanical nonlinear threshold. Further, the results showed that when the loading frequency was increased from 5 to 15 Hz under equal amplitude, the response waveform remained unchanged, however, the electrical displacement was attenuated by 19.7%. Packaging schemes using various lengths and thicknesses of an epoxy layer were conducted by using simulation. It is indicated that, under the premise of ensuring the protection package and considering the manufacturing process, the length of the package side could increase appropriately, and the single-side package side length is set to 4 mm. When the thickness of the package layer becomes less, it would be better.