Bending and vibration performance of curved carbon fiber reinforced polymer pyramidal sandwich structure

The bending and vibration characteristics of the curved carbon fiber reinforced polymer pyramidal sandwich structure were studied. The hot pressing one-time molding process was used to prepare the curved carbon fiber reinforced polymer pyramidal sandwich structure. A three-point bending test was conducted to explore the bending damage load and damage mode of the structure. The results show that the load-displacement curve of the structure can be divided into 4 stages: Linear stage, damage initiation stage, damage evolution stage and failure stage. The main failure modes are panel collapse and node failure. The ABAQUS display solver was used to establish the effective bending and vibration model. The failure modes and load-displacement curves of the bending damage process, the structural vibration modes and natural frequencies were obtained. The effects of different parameters (geometric parameters, material properties) on the bending and vibration performance were discussed, and the natural frequencies were compared to the impact of various boundary conditions. The results show that an increase in relative density (panel thickness, core diameter) increases the bending failure load and natural frequency of the structure. But increasing the core angle ω leads to a decrease in the bending failure load and natural frequency. The greater the specific stiffness of the material is, the higher the natural frequency will be.