GPL-Reinforced composite piezoelectric microcantilever dynamics in atomic force microscope

Abstract

Currently, Atomic Force Microscope (AFM) is utilized as an efficient tool for nanoscale measurements and nanomanipulation of particles. The central part of AFM is considered to be the microcantilever (MC) used in the device. AFM MC is generally made from silicon. Since functionally graded graphene-nanoplatelet-reinforced composite (GPLRC) materials are highly popular in industry and academic research, the present study aims to be the first attempt to investigate the possibility of utilizing these materials in AFM MC. Also, it seeks to compare the nonlinear vibrational behavior of the MC made from this type of material with that of the silicon MC and also to investigate the vibrational behavior of the GPLRC MC in interaction with the sample surface. To do so, the GPLRC MC vibrated with the piezoelectric layer on its top is utilized. In order to increase the sensitivity of the MC to the interaction force between the surface and the probe tip, the tip of the MC is considered narrower. The differential equation of the vibrational motion of the MC near the surface of the sample is derived by considering the Lennord-Jones model according to the Euler-Bernoulli theory and applying the Lagrange method. In order to solve the nonlinear differential equation of motion with partial derivatives in terms of the time and the position of each point on the MC, Galerkin variable-separation method and multiple time scale (MTS) method are applied. The results of the dynamic modeling near the surface of the sample indicate that the MC made of GPLRC is more sensitive to the nonlinearity of the interaction force as compared to the common silicon MC.