Electrical Properties of PZT Under High-Pressure Stress Pulse Effects of Loading Frequency and Circuit Load

Abstract

The research on the discharge characteristics of PZT under conventional applications has made good progress. In theory, the piezoelectric equation can be used to describe the relationship between stress and electrical output. However, existing studies have shown that the relationship becomes nonlinear under high-pressure stress pulses. To study the effect of loading frequency and circuit load on the electrical output performance of PZT under high-pressure stress pulse, the experiment was carried out based on the split Hopkinson pressure bar and a dynamic & static universal test machine. The effects of different circuits load on the output voltage under high-frequency and low-frequency high-pressure stress pulses are analyzed. Both theory and experiments prove that the critical open-circuit measurement resistance (Rcritial) of PZT decreases with the load frequency. The output voltage is positively correlated with the load resistance when the load resistance is less than Rcritial. It is confirmed by loading different circuits (diodes are added in different positions) that reverse positive charge appears at the negative pole of the material during the stress unloading stage. PZT have the maximum dischargeable strain Tunder the high-pressure stress pulses. PZT no longer generates induced charges when the strain is greater than h. When constant strain rate loading makes PZT completely release energy, its open-circuit output voltage is proportional to the strain rate.