Experimental and numerical analysis of the dynamic behavior of a bio-based sandwich with an auxetic core

Abstract

This paper presents the experimental and numerical analysis results of the damping properties of a bio-based sandwich with an auxetic core. The skins and core of the sandwich structure are made from the same material which is a polylactic acid reinforced with flax fibers. A 3D printing technique was used to produce the sandwich structures. Experimental tests were conducted on the skins, the auxetic structure and the sandwich beams to evaluate their damping properties. Vibration tests were performed in a clamped-free configuration. Those tests were carried out on two different configurations and four core densities of the auxetic structures in order to investigate their effect on the damping factors and dynamic stiffness. Furthermore, finite element analysis was used to validate the experimental results. The resonance frequencies and the loss factor obtained from experimental and numerical analysis were in close agreement. Finally, a study of the effect of each sandwich component on energy dissipation was carried out in order to understand the dynamic response of such beams.