Damping characterization of monolithic and reinforced magnesium using an integrated suspended beam method and a new circle-fit approach

Abstract

In the present study, a new technique of using the free-free beam method coupled with a circle-fit approach is used to determine the damping of monolithic and SiC reinforced magnesium. This technique is based on the classical vibration theory which relates the geometry and material properties to the resonant frequency and the structural damping of the test specimen. Using the fact that, for each resonant frequency of the test specimen, the ratio between the vibration response and the applied force fits to a circle in the Argand plane, the damping factor and the natural frequency is predicted accurately for the test specimen. An attempt is made to explain the increase in damping capability of the composite specimen compared to the monolithic specimen in terms of an increase in the dislocation density and by the presence of a plastic zone at the matrix-particulate interface.