Comprehensive Hydromechanical and Free Vibration Investigation of Aluminum/Axetic-Graphene/PZT-5H Multilayer Microcantilevers in Fluid Media, a Study Based on Timoshenko Beam Theory and GDQ Method

Document Type : Original Article

Authors
1 Department of Aerospace Engineering, Faculty of Graduate Studies, Shahid Satari University of Aeronautical Sciences and Technology, Tehran, Iran
2 Assistant Professor, Department of Aerospace Engineering, Shahid Sattari University of Aeronautical Sciences and Technology, Tehran, Iran
3 Department of Mechanical Engineering, Iran University of Science and Technology, Tehran, Iran
Abstract
Piezoelectric microcantilevers are important energy conversion elements in microelectromechanical systems for applications such as biosensors, energy harvesting, and underwater acoustic detection. In this study, the vibration behavior of a three-layer composite microcantilever with dimensions of 6 × 125 × 500 μm, consisting of a PZT-5H piezoelectric layer, a graphene-reinforced acoustic core with negative Poisson's ratio, and an aluminum base layer, is investigated. Free vibration analysis is performed using Timoshenko beam theory and the generalized difference-of-squares method, and the effect of fluid-structure interaction is considered through an added mass model and viscous damping. The analytical results are validated by 3D simulation in COMSOL Multiphysics software and show an error of less than 0.74% for the first seven modes. The results show that the use of an austenitic-graphene core with νa = −0.30 results in a 1.85% increase in the first mode frequency and a 34% improvement in shear stiffness compared to conventional cores, while the frequency ratio in water to air remains almost constant at 0.910. Modal energy analysis shows that the PZT layer absorbs about 52.8% of the bending energy and nearly 90% of the viscous dissipation occurs in the last 2.6% of the beam length. Also, sensitivity analysis shows that placing the microcantilever close to the free surface increases the frequency by about 0.6 to 1.5%, and proximity to the rigid bottom reduces it by about 1 to 3%, and this effect is intensified by increasing the density and viscosity of the fluid.
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Articles in Press, Accepted Manuscript
Available Online from 28 September 2026

  • Receive Date 08 June 2026
  • Revise Date 05 September 2026
  • Accept Date 28 September 2026
  • First Publish Date 28 September 2026
  • Publish Date 28 September 2026