Experimental investigation on impact, sound, and vibration response of natural-based composite sandwich made of flax and agglomerated cork

Abstract

In recent years, material scientists have been focusing on the utilization of materials from natural resources due to environmental concerns. In the same context, the aim of this work is to evaluate impact response, sound absorption behavior, and vibration damping characteristics of natural-based composite sandwich made of flax as skin reinforcement and agglomerated cork as core. Vacuum bagging method was used for manufacturing composite sandwiches with different cork densities of 240, 280, and 340 kg/m3. Composite sandwiches have also been manufactured by using glass as skin reinforcement for comparison. Low velocity impact test was conducted and found that glass fiber reinforced composite sandwich required 73–77% more energy to perforate when compared to the flax fiber reinforced composite sandwich irrespective of core density. Flax fiber reinforced composite sandwich has 45–96% higher sound absorption capacity and 27–32% higher vibration damping ratio than glass fiber reinforced composite sandwich irrespective of core density. This is due to multiscale structure and cellular nature of the flax fiber and the cork materials, respectively. These enhancements in sound and vibration are accomplished with just little forfeits in perforation energy. This study recommends that, if optimized, the natural-based composite sandwich could be an ecologically appealing answer for automobile and construction applications, where impact behavior is important, along with sound and vibration properties.