Damping and Mechanical Properties of Hybrid Laminates Composed of High- and Low-Modulus Epoxy CF Prepregs

Carbon fiber reinforced polymer composites (CFRP) are widely employed in high-end load-bearing structures. However, their inherently low damping capacity and the trade-off relationship with stiffness pose challenges in meeting the integrated requirements of load-bearing and vibration reduction. To address this issue, this paper proposes a novel interlayer hybrid damping design strategy based on high-/low-modulus epoxy resin-based carbon fiber (CF) prepregs. This approach utilizes high-modulus prepregs to maintain structural stiffness while employing low-modulus, high-loss prepregs to dissipate vibrational energy, achieving synergistic optimization of damping and stiffness through controlled hybrid ratios. Results demonstrate that this strategy, leveraging the dual energy dissipation mechanisms of high internal loss characteristics in low-modulus components and interfacial friction induced by modulus mismatch, achieves a maximum enhancement of 152.21% in modal damping ratio. Meanwhile, mechanical properties are influenced by the weighted contributions of component properties and interfacial stress concentration effects, resulting in maximum reductions of 11.87% in modal frequency and 25.41% in bending stiffness, respectively. This study breaks through traditional design limitations and provides a new approach for addressing the integrated design challenges of load-bearing and vibration reduction in CFRP applications. Graphical Through the synthesis of a type of high-loss and low-modulus prepreg resin, the hybrid damping design of high-/low-modulus resin carbon fiber prepregs is realized, and the contradictory balance between the damping and stiffness of CFRP is improved.