Size-Dependent Dynamics of Perforated and Short-Fiber-Reinforced Nanowires Based on Non-local Modified Couple Stress Theory

Abstract

Purpose: This article aims to presented the size-dependent free vibration response of short-fiber-reinforced and perforated nanowires restrained with deformable springs at both ends, taking into account non-local modified couple stress theory. Methods: This study is conducted using Euler-Bernoulli beam theory and non-local modified couple stress theory. Hamilton's principle is used to derive the equations of motion of short-fiber reinforced and perforated nanowires. An analytical method based on a Fourier sine series and Stokes' transform is adopted to solve the free vibration problem. Results: A number analyses are carried out to examine the effects of the material length scale parameter, short fiber properties, perforation properties and deformable boundaries on the free vibration of the nanowires. Conclusion: According to the analysis results, it is determined for SFR nanowires that increases in the Ef/Em ratio and l/d ratio increase the frequencies, while increases in the ρf/ρm ratio decrease the frequencies. Similarly, for perforated nanowires, increment in filling ratio increases the frequencies while increment in number of holes decreases the frequencies. In addition, the non-local parameter and material length scale parameter decreases and increases of both short-fiber-reinforced nanowire's and perforated nanowire's frequecies, respectively.