Temperature characteristics testing and modifying of piezoelectric composites

The current ceramic/618 epoxy resin piezoelectric composite material is easily deformed due to temperature, which affects the performance of the transducer to send and receive signals. Therefore, finding piezoelectric composite materials with higher temperature stability has become an urgent task. In this paper, the temperature stability of two piezoelectric composite materials of ceramic/ 618 epoxy resin and ceramic/9110 W silicone resin in the range of 25 °C ~ 120 °C was investigated via the fiber Bragg grating method. The results show that, during 25 °C to 120 °C, the ceramic/9110 W silicone resin piezoelectric composite has obvious less deformation and more stable electromechanical properties than the ceramic/ 618 epoxy resin piezoelectric composite; its increase rate of deformation in three directions of length, width and thickness are 8.269 × 10⁻⁵ mm/°C, 6.728 × 10⁻⁶ mm/°C, and 8.476 × 10⁻⁶ mm/°C respectively; its resonant frequency, relative rate of change of frequency constant, quasi-static capacitance, relative dielectric constant and conductance increase with increasing temperature, and the maximum values are 289 kHz, 0.1529%, 1.67 nF, 1083.225 and 11.300 ms, respectively; its electromechanical coupling coefficient changes little with increasing temperature, the maximum and minimum values are 0.63 and 0.60, respectively. The ceramic/9110 W silicone resin piezoelectric composite can better ensure the stability of the transducer performance.