PVDF压电薄膜传感特性研究

聚偏氟乙烯(PVDF)压电薄膜是一种压电高分子材料,它具有独特的压电效应,被广泛应用于振动测量等各个领域。但对于压电薄膜在受到外加应力时其输出特性的研究较少。该文理论分析了PVDF压电薄膜的传感机理和电路等效模型;然后利用COMSOL软件进行仿真;最后实验研究了PVDF压电薄膜在不同激励振幅、激励频率及外加应力下的动态响应。研究结果表明,压电薄膜输出信号的幅值与薄膜振幅成线性关系,与所受外加静态应力无关。

Studies on Sensing Properties of PVDF Piezoelectric Films

The polyvinylidene fluoride (PVDF) piezoelectric thin film is a kind of piezoelectric polymer material. It has unique piezoelectric effect, and is widely used in vibration measurement and other fields.There are few reports on the output characteristics of piezoelectric thin films under applied stress. In this paper, the sensing mechanism and the equivalent circuit model of PVDF piezoelectric film are analyzed theoretically. And then the numerical model of piezoelectric film is simulated by COMSOL software. Finally, the dynamic responses of PVDF piezoelectric films with different excitation frequency, vibration amplitude and external stress are studied experimentally. The results show that the output signal amplitude of piezoelectric film has a linear relationship with the amplitude of the film, but not directly related to the external stress of the film.