Influence of Vibration Fatigue on Electric Induced Response of Piezoelectric Cantilever Plates

According to the dynamic design of piezoelectric smart structures, the impacts of vibration fatigue on the electric induced response of bimorph piezoelectric cantilever plates were studied. Excited by external potential, the variation of the free end displacement of piezoelectric cantilever plates, the actuating layer root strain, and the generation voltage of sensing layer with the vibration fatigue cycles were tested. Besides, we analyzed the impacts of the excitation voltage amplitude and voltage waveform on the displacement, strain and the generating voltage. And the displacement response, strain response, generating voltage response are also discussed. The results show that under the excitation voltage of 45~50 V, greater excitation voltage amplitude, would makes decreased electric induced response amplitude of piezoelectric cantilever plates, and faster fatigue damage rate. The sine wave excitation is more prone to cause fatigue compared to triangle wave. Moreover, as the fatigue damage of piezoelectric cantilever plates is nonlinear, the displacement-strain curves before and after fatigue are no longer consistent, and the root strain of piezoelectric cantilever plates at resonance decreases after the fatigue damage. The experimental results can provide data support for the dynamic design of piezoelectric smart structures.