FEM implementation of the nonlinear damage evolution model for piezoelectric material under bipolar electrical fatigue load

Abstract

The service life of piezoelectric actuator is significantly affected by the high electric fatigue load. Predicting damage evolution in piezoelectric materials under high electric load is essential for the reliability and life prediction of piezoelectric structures and devices. In this paper, a nonlinear damage evolution FE model and its acceleration program are proposed which are capable of modeling nonlinear damage evolution of piezoelectric material and structure under high electric fatigue load. The simulation results of degraded piezoelectric constant varying with the number of cycles are compared with the experimental results, and a well agreement verifies the validity of the nonlinear damage evolution FE model. Moreover, the damage distribution evolution of piezoelectric multi-layer actuator with standard double comb electrode is studied by the proposed nonlinear damage evolution model. The driving performance of piezoelectric multi-layer actuator decreases rapidly under the high electric fatigue load, where the damage area starts from the tip of the electrode and gradually spreads to the area between the electrodes. Based on the nonlinear damage evolution and its FEM implementation, the damage distribution and evolution for piezoelectric structures with variable amplitude bipolar electrical fatigue load can be obtained. This provides a reliable reference for the life prediction and application of the piezoelectric actuator.