Application of Auxetic Core to Improve Dynamic Response of Sandwich Panels Under Low-Velocity Impact

Using high-order shear and normal deformation theory (HSNDT), this study analyzes the dynamic response and time history of the impact force of the sandwich plate with the auxetic core under low-velocity impact. The impact was modeled using a two-degree-of-freedom mass and spring model, and the Hertz linearized model was utilized to derive the contact force's time history. The rectangular sandwich panel has simple supported boundary conditions and consists of three layers: two aluminum top face sheets and one auxetic core layer with a negative Poisson's ratio. Using the energy technique, the system's governing equations are derived. The equilibrium equations were solved by the analytic approach of the Navier method in the space domain and the numerical method of Newmark in the time domain. The use of HSNDT distinguishes this article from others on similar topics, and the flexibility of the thick core in the thickness direction is considered. The Effects of different geometric and material properties have been investigated, and the results have been compared with those of other similar papers and studies for validation. The data indicate that the greater the degree of inclination of the cell, the longer the impact period and the lower the peak impact force. Moreover, the larger angle of the auxetic cell reduces the deflection at the impact site. In terms of minimizing deflection, the auxetic honeycomb sandwich panel is 25% superior to the non-auxetic honeycomb panel.