Bending failure mechanisms and free vibration properties of three-dimensional irregular and integrally manufactured composite sandwich structures

This article proposes carbon fiber-reinforced regular and irregular and integrally manufactured composite sandwich structures and investigates their bending and free vibration performance through theoretical, numerical finite element, and experimental methods. The study elucidates the impact of structural bending strength, energy absorption, and natural frequency on these sandwich structures. The flexural modulus and energy absorption of the lattice sandwich structure under three-point bending experiment are examined. The vibration performance of the composite lattice sandwich structure is then explored both theoretically and numerically. A finite element model simulating the three-point bending and free vibration characteristics of the lattice sandwich structure is established, and the effects of material properties and geometric structures on the mechanical performance of the composite lattice sandwich structure are discussed. The comparison between experimental results and simulation outcomes shows good consistency. This comprehensive study provides a theoretical and experimental basis for the application and optimization of lattice composite sandwich structures for engineering applications.