Enhanced damping characteristics of carbon fiber reinforced polymer–based shear thickening fluid hybrid composite structures

Lightweight carbon fiber reinforced polymer composite structures with high stiffness are at risk of resonant vibration. Our study proposes a methodology to reduce this risk by passively improving the damping ratio of carbon fiber reinforced polymer composite structures. We developed shear thickening fluid hybrid composite structures by applying polyimide tubes filled with shear thickening fluid having rheological properties into a composite laminate. In order to verify the proposed methodology, carbon fiber reinforced polymer–based shear thickening fluid hybrid composite beams were fabricated, and modal tests were subsequently performed to investigate their dynamic characteristics. The results revealed that the damping ratios for the initial six vibration modes of the carbon fiber reinforced polymer–based shear thickening fluid hybrid composite beam increased by 38%–174%; however, their Young’s modulus and tensile strength, respectively, decreased by 11.25% and 14.08% when compared to those of normal carbon fiber reinforced polymer composite beams. We believe that the proposed methodology to improve the damping ratio will contribute in reducing the risk of vibration resonance of carbon fiber reinforced polymer composite structures in various applications.