薄膜压电驱动器驱动均匀气体压力载荷时具有不同的形变特征.根据基尔霍夫薄板原理，采用最小能量法和里兹法建立了圆形薄膜压电驱动器耦合均匀压力载荷条件下的静态形变模型.分别在电压驱动、压力驱动以及电压与压力共同驱动条件下，实验测试了驱动器的形变特征，并与计算模型对比，发现最大相对误差在9.3%以内，验证了模型的可靠性.基于建立的形变模型，分别讨论了驱动器压电层与弹性基层的半径比和厚度比对驱动器形变的影响，分析了均匀压力载荷条件下驱动器的形变特性.结果表明，薄膜压电驱动器存在最佳的半径比和最佳的厚度比，并且在均匀压力载荷下，驱动器半径比低于0.71时会明显导致驱动器的边缘处出现反向形变，不利于驱动.
Analytical equations are developed to calculate the static deflection of a circular diaphragm-type piezoactuator under loads of driving voltage and uniform resisting pressure. The solution is derived using the energy minimization method and the Rayleigh-Ritz method based on the Kirchhoff thin plate theory. The proposed solution is validated via the experimental measurements under loads of voltage only, pressure only, and combined loads of voltage and pressure, respectively. The analytical and experimental results agree within 9.3%, which suggests the solution is accurate. Based on the proposed equations, the effects of the radius ratio and thickness ratio of the lead zirconate titanate (PZT) layer to the passive layer on the actuator deflections are investigated. Moreover, the effects of the pressure loads on the actuator deflections are studied as well. The results indicate that there exist the optimal radius ratio and the optimal thickness ratio to generate maximum stroke volume. It is also observed that the diaphragm deforms reversely near the periphery under the pressure load when the actuator radius ratio is lower than 0.71, which weakens the actuator performance.
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