Effects of base material and magnetic field on the dynamic response of MR-laminated composite structures

Abstract

Stability and vibration control are major challenges for applications in which laminated composite beams are being used. Using composite base materials with higher strength and/or using appropriate layout orientation are the two potential methods to improve the dynamic performance of laminated composite structures. However, using composite materials with higher strength significantly increases the manufacturing cost. Recently, layers/segments of Magnetorheological (MR) fluids have been added to the common laminated beams, the so-called MR-laminated beam, to improve the dynamic characteristics of such structures. The present work investigates the effect of base materials and applied magnetic field on the dynamic response of MR-laminated beams. Different composite materials, including E-glass, carbon fiber, and Kevlar, have been used as base materials to build the sandwich MR-laminated beam. The hollow spaces of the sandwich beam are filled with MR fluid to fabricate a testing sample for experimental purposes. A modified layerwise theory, N-layer, has been used to determine the vibration response of the structures. It is concluded that applying a magnetic field increases the natural frequency of the MR-laminated beam. In fact, applying 1400-Gauss magnetic fields to a low-cost material like E-glass provides the same natural frequency as that of the fiber-carbon without magnetic fields.